DISTRIBUTION AND ABUNDANCE OF WATERFOWL AND
SUBMERGED AQUATIC VEGETATION IN THE CHESAPEAKE
BAY
Robert E. Munro and Matthew C. Perry
CBP-TR-001S
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60OR81103
DISTRIBUTION AND ABUNDANCE OF WATERFOWL AND
SUBMERGED AQUATIC VEGETATION IN THE CHESAPEAKE
BAY
Robert E. Munro and Matthew C. Perry
CBP-TR-001S
><*&&
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EPA Report Number
April 1981
DISTRIBUTION AND ABUNDANCE OF WATERFOWL AND
SUBMERGED AQUATIC VEGETATION IN CHESAPEAKE BAY
by
Robert E. Munro
and
Matthew C. Perry
U.S. Fish and Wildlife Service
Migratory Bird and Habitat Research Laboratory
Laurel, Maryland 20811
Interagency Agreement Number EPA-78-D-X0391
Project Officer
William A. Cook
Chesapeake Bay Program
U.S. Environmental Protection Agency
Region III
6th and Walnut Streets
Philadelphia, Pennsylvania 19106
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
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TECHNICAL REPORT DATA
(Please read Inunctions on the reverse before completing)
REPORT NO.
2.
3. RECIPIENTS ACCESSION-NO.
TITLE ANO SUBTITLE
Distribution & Abundance of Waterfowl and Submerged
Aquatic Vegetation in the Chesapeake Bay
5. REPORT DATE
April, 1981
6. PERFORMING ORGANIZATION CODE
. Munro and Matthew C. Perry
8. PERFORMING ORGANIZATION REPORT NO.
CBP-TR-001S
9. PERFORMING ORGANIZATION NAME ANO ADDRESS
U. S. Fish & Wildlife Service, Migratory Bird and
Habitat Research Laboratory, Laurel, Maryland 20811
10. PROGRAM ELEMENT NO.
2BA703
11. CONTRACT/GRANT NO.
EPA 78-D-X0391
12. SPONSORING AGENCY NAME AND ADDRESS
Region III, U. S. Environmental Protection Agency
Chesapeake Bay Program,2083 West Street
Annapolis, Maryland 21401
13. TYPE OF REPORT ANO PERIOD COVERED
Project Report 8/1/78-12/31/80
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT waterfowi species populations in Maryland & Virginia portions of Chesapeake
Bay were examined during long-term' and current (1972-1980) periods to identify trends in
distribution and abundance. Comparisons were also made between State and Atlantic Fly-
way populations & waterfowl species distributions among survey areas. Distribution &
abundance of SAV among waterfowl survey areas in Md. were summarized for 7 plant species
during 9 years (1971-1979). These data (SAV species combined) were used to test the
hypothesis that annual variation in area populations of waterfowl was related to varia-
tion in the abundance of SAV, following an adjustment for annual variation in the genera
abundance of waterfowl.The distribution and abundance of SAV species declined in Md.
waters during the 1970's. There were few statistically significant relationships betwee
distribution and abundance of waterfowl and SAV. But there was an implied biological
relationship, since the most important waterfowl wintering areas were also among the
most abundantly vegetated areas. This report was submitted in partial fulfillment of
Interagency Agreement No. EPA-78-D-X0391 by the U. S. Fish and Wildlife Service,
Migratory Bird and Habitat Research Laboratory under the sponsorship of the Chesapeake
Bay Program, U. S. Environmental Protection Agency.
17.
KEY WORDS ANO DOCUMENT ANALYSIS
DESCRIPTORS
b.lOENTIFIERS/OPEN ENDED TERMS
COSATl Field/GrouD
15. 2i37P.i5U7:GN STATEMENT
Unrestricted distribution
j 19. SECURITY CLASS iThis Report/
1 Unclassified
NO. OF PAGES
193
20. SECURITY CLASS (This page j
Unclassified
22.
EPA Form 2220-1 (9-73)
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TECHNICAL INFORMATION CLEARANCE
1. DATE PREPARED
6/11/81
2. LAB/OFFICE DRAFT NO.
3. COPYRIGHT PERMISSION
(/ one)
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5. PRESENT TITLE Distribution & Abundance of
Waterfowl and Submerged Aquatic Vegetatioi
_in__£he. .Chesapeake _Bay_-
a. TECHNICAL INFORMATION PLAN
I TITLE AND REFERENCE
6. AUTHOR. ORGANIZATION. AND ADDRESS.
Robert E. Munro & Matthew C. Perry
U. S. Fish &. Wildlife Service, Migratory &
Bird Habitat Research Lab, Laurel, Md. 208!
EPA PROJECT DOCUMENTATION
7. SERIES
8. REPORT DATE
April, 1981
9. CONTRACT/GRANT/IAG NUMBER
EPA 78-D-X0391
10. TYPE OF MATERIAL (/ one)
SPECIFY (WHERE NECESSARY)
H RESEARCH REPORT
& PROJECT REPORT AND PROJECT SUMMARY
D JOURNAL PUBLICATION (include journal name)
O UNPUBLISHED REPORT
Q AUDIO VISUAL
D MEETING/PUBLICATION *
D APPLICATIONS GUIDE
O SUMMARY/SYNTHESIS
O RESPONSE REPORT
It: PROJECT OFFICER/IN-HOUSE AUTHOR
a. SIGNATURE
b. DATE
c. TYPED NAME AND ADDRESS
William A. Cook, EPA, Chesapeake. Bay Program
2083 West. St., Annapolis, Md. 21401
d. FTS TELEPHONE NO.
FTS 922-3912
12: TECHNICAL INFORMATION (PROGRAM) MANAGER
a. SIGNATURE
c. TYPED NAME AND ADDRESS
Dorothy Van Dorfe» .
EPA, Chesapeake.Bay Program, 2083 West St.
Annapolis, Md. 21401. "
t 1 a.. COMMENTS
b. DATE
d. FTS TELEPHONE NO.
FTS 922-3912
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DISCLAIMER
This report has been reviewed by the Environmental Research
Laboratory - Narragansett, Chesapeake Bay Program of the U.S.
Environmental Protection Agency, and approved for publication. Approval
does not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does mention
of trade names or commercial products constitute endorsement or
recommendation for use.
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ABSTRACT
Waterfowl species populations in Maryland and Virginia portions of
Chesapeake Bay were examined during long-term and current (1972-80)
periods to identify trends in distribution and abundance. Comparisons
were also made between State and Atlantic Flyway populations, and
waterfowl species distributions among survey areas.
Distribution and abundance of submerged aquatic vegetation (SAV)
among waterfowl survey areas in Maryland were summarized for seven plant
species during nine years (1971-79). These data (SAV species combined)
were used to test the hypothesis that annual variation in area
populations of waterfowl was related to variation in the abundance of
SAV, following an adjustment for annual variation in the general
abundance of waterfowl.
Waterfowl food habits were summarized and analyzed when possible.
These data provided additional evidence on relationships between
waterfowl and SAV, and indications of changing food preferences within
some species*
Recent Maryland waterfowl populations (with one exception).
generally declined, while those in Virginia increased or remained
stable. Species dispersion among areas was typically stable. The most
important waterfowl wintering areas in Chesapeake Bay have been and
continue to be the Chester River, Eastern Bay, and the lower Choptank
River.
The distribution and abundance of all SAV species declined in
Maryland waters during the 1970's. During that period, SAV was most
abundant in areas that included the lower Choptank River, Manokin and
Annemessex Rivers, Chester River, and Eastern Bay.
iv
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There were few statistically significant relationships between
distribution and abundance of waterfowl and SAV. But there was an
implied biological relationship, since the most important waterfowl
wintering areas were also among the most abundantly vegetated areas.
Waterfowl species adapted differently to the decline of SAV during
the 1970's. Whistling swans began feeding in agricultural fields, while
others shifted food preferences from SAV to invertebrates. However, the
most common adaptation was to winter elsewhere in the Atlantic Flyway.
Due to the northern location of Chesapeake Bay, through which many
waterfowl annually migrate, current populations of some species are
believed to be temporarily low. When exposed to increased distribution
and abundance of submerged aquatic vegetation, we anticipate that
waterfowl species with preferences for SAV and associated invertebrates
will respond positively.
This report was submitted in partial fulfillment of Interagency
Agreement No. EPA-78-D-X0391 by the U.S. Fish and Wildlife Service,
Migratory Bird and Habitat Research Laboratory under the sponsorship of
the Chesapeake Bay Program of the U.S. Environmental Protection Agency.
This report covers the period August 1, 1978, to December 31,1980, and
work was completed as of February 15, 1981.
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CONTENTS
Foreward • ill
Abstract iv
Acknowledgment viii
Executive Summary ix
1. Introduction 1
2. Conclusions 4
3. Materials and Methods 7
Sources and limitations of data 7
Waterfowl food habits 7
Waterfowl populations ..... 9
Submerged aquatic vegetation 13
Statistical analyses 14
4. Results and Discussion 16
Waterfowl food habits. 16
Distribution and abundance of SAV 25
Chesapeake Bay waterfowl populations in perspective. ... 31
Maryland 31
Virginia 40
Effects of SAV on v/aterfowl 45
Swans and geese 46
Black ducks and mallards 48
Diving ducks 48
Impacts of waterfowl on SAV 59
References 60
Appendices
A. Scientific and common names of waterfowl food items 62
vi
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B. Food items of waterfowl during the period 1890-1959 71
C. Food items of waterfowl during the period 1960-1969 107
D. Food items of waterfowl during the period 1970-1979 128
E. Frequency occurrence of SAV by species during 1971-1979 • • • .152
F. Summary of Maryland waterfowl populations by species and area .159
G. Summary of Virginia waterfowl populations by species and area .172
vii
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ACKNOWLEDGMENTS
We are indebted to B. K. Williams (primary responsibility), P. H.
Geissler, L. M. Moyer, and E. D. Heinlein for statistical consultation.
We also thank V. G. Perros, L. D. Eastman, C. J. Ellis, P. Longabucco,
P. L. Miller, and J. M. Wilcox for technical assistance. -Many people
assisted in food habits, analyses used in this report and their input is
appreciated. Of special importance were C. K. Rawls for his work during
the 1960's, and F. M. Uhler whose contributions have spanned decades.
V. D. Stotts (Maryland Wildlife Administration) offered advice and
expertise on Maryland waterfowl populations, as well as access to
original data from periodic surveys of submerged aquatic vegetation. To
the many pilots and biologists who participated in surveys of waterfowl
or vegetation in Chesapeake Bay, we express our gratitude. H. F.
Percival and B. S. Brun provided valuable administrative expertise. We
are finally indebted to G. M. Haramis, C. F. Kimball, and J. D. Nichols
for their critical review of this report.
viii
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EXECUTIVE SUMMARY
The Chesapeake Bay is the largest estuarine system along the
Atlantic coast of North America, and the most important wintering area
in the Atlantic Flyway for more than 1.5 million waterfowl (including
ducks, geese, and swans). Historically (1956-), the Maryland portion of
the Bay has been the principal Flyway wintering area for Canada geese
(Branta canadensis), whistling swans (Cygnus columbianus columbianus),
and canvasbacks (Aythya valisineria), and a primary wintering area for
ruddy ducks (Oxyura jamaicensis), common goldeneyes (Bucephala clangula
americana), redheads (_A. americana), black ducks (Anas rubripes), and
mallards (_A. platyrhynchos). In addition to wintering other popul-
ations, the Bay provides a resting and feeding place for countless birds
that migrate to and from wintering areas farther south. The Bay is
therefore vital as a wintering area and as a link in a chain of resting
areas.
The traditional importance of Chesapeake Bay to waterfowl was due
in large measure to vast beds of submerged aquatic vegetation, which
included species such as widgeongrass (Ruppia maritima), wildcelery
(Vallisneria americana), and sago pondweed (Potamogeton pectinatus).
But during the 1970's those waterfowl food resources declined, which in
large measure prompted this work. The main objectives of this report
are to document historic and current distribution, abundance, and food
preferences of waterfowl that winter in Chesapeake Bay, and examine
current relationships between waterfowl and the distribution and
abundance of SAV.
Linear regression and analysis of variance techniques were used to
detect trends in distribution and abundance of waterfowl species
ix
-------
populations that winter in Maryland and Virginia, and to examine
waterfowl-SAV relationships with simple, linear models. Waterfowl food
habits were analyzed where possible with a ranking procedure, which
compared historic and current usage of important food items.
Maryland and Virginia waterfowl populations differed considerably
in species diversity and numbers of birds. The smaller Virginia
populations were also more stable than those in Maryland. However,
distributions of species populations among survey areas in both States
were very consistent over years.
Distribution and abundance of SAV in Maryland waters declined
during the 1970's, and particularly from 1971 to 1973. Of the seven SAV
species considered, all declined; however, widgeongrass remained
relatively abundant and widely distributed. SAV was most abundant in
the lower Choptank River, Manokin and Annemessex Rivers area, Chester '
River, and Eastern Bay during the 1971-79 period.
The common response by waterfowl species with known preferences
for SAV (e.g., redheads, American wigeon [Anas americana], and pintails
[A. acuta]) was to winter elsewhere in the Atlantic Flyway during the
1970's. Others (whistling swans and canvasbacks) changed food
preferences. The wintering Canada goose population in Maryland, which
now requires only open water for protection and agricultural fields for
food, continued a long-term increase in numbers.
The distribution (dispersion) and abundance of waterfowl populations
among Maryland survey areas generally reflected the distribution and
abundance of SAV, although few statistically significant relationships
were found. The areas most important to wintering waterfowl (Chester
River, Eastern Bay, and the lower Choptank River) prior to and during
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the 1970's were also among the most abundantly vegetated areas during
the 1970's. It follows from this general relationship that waterfowl
populations have had no adverse or long-term impact on distribution and
abundance of submerged aquatic vegetation.
The currently low diversity of waterfowl species wintering in
Maryland is believed to be temporary, and limited by the distribution
and abundance of SAV. Since formerly abundant species of waterfowl
still migrate annually through the Bay area, a positive and rapid
response to an improvement in distribution and abundance of submerged
aquatic vegetation may be anticipated.
xi
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SECTION 1
INTRODUCTION
Chesapeake Bay, the largest estuarine system in North America,
contains a diverse collection of many plant and animal communities.
Waterfowl (Anatidae) are among the most prominent animals during fall
and winter. Of 45 species of ducks, geese, and swans that are native to
North America (Bellrose 1976), about 30 regularly migrate through or
winter in the Bay area (Stewart 1962). Although a few species such as
the black duck (Anas rubripes) and the mallard (A. platyrhynchos) breed
in Bay marshes, most waterfowl are present in the area only from October
through March. The use and importance of Chesapeake Bay to waterfowl
are therefore greatest during this period.
Historically, the Bay has been the most important wintering area
along the Atlantic coast for a number of waterfowl species, such as the
whistling swan (Cygnus columbianus columbianus), Canada goose (Branta
canadensis), and the canvasback (Aythya valisineria). Other populations
have been far less abundant. Early migrants such as blue-winged teal
(Anas discors) spend little time in the Bay before departing in
mid-October for wintering areas in South America. Some winter
residents, due to their habitat preferences, are not obvious to the
casual observer. For example, the sea ducks or scoters (Melanitta
spp.), as their colloquial names imply, occupy deep (>3 m), open-water
habitats generally beyond the littoral zone. Others, such as the
Atlantic brant (Branta bernicla hrota), are usually found only in ocean
bay habitats (e.g., Sinepuxent Bay, Maryland).
Ducks are often referred to as either surface-feeding or puddle
ducks, as opposed to diving or bay ducks. Puddle ducks feed by dabbling
-------
at the water's surface or tipping up in shallow water, even though they
are capable of diving beneath the water's surface. They typically
prefer shallow marshes and shoal riverine habitats, and as a group they
consume more plant material than do diving ducks. The diving ducks all
share two physical characteristics that facilitate diving, their primary
method of feeding: their wings are relatively small and their legs are
set farther back on their body. As a consequence, divers need open
water across which to run prior to flight, which prevents them from
feeding in dense marshes or agricultural fields. Diving ducks are
usually found in exposed, deeper waters (1-5 m), where vegetation is
less available.
Submerged aquatic vegetation (SAV) is an important food resource
for many waterfowl species (Cottam 1939; Martin and Uhler 1951; Yocom
1951; Stewart 1962; Bellrose 1976). In his account of the canvasback,
Bent (1923:195) reported ". . . it [wildcelery (Vallisneria
americana)] grows most abundantly in the Chesapeake Bay region and is
supposed to be the chief attraction for the vast number of canvasbacks
and other ducks which resort to these waters in winter . . .". The
traditional importance of the Bay to many waterfowl populations provides
indirect evidence of a long-term stability in the Bay's aquatic plant
and animal food resources. But waterfowl populations and the food
resources upon which they depend are not stable in the short-term.
There have been changes in waterfowl distribution and abundance in the
Bay during the last 25 years, as well as more recent changes in
distribution and abundance of SAV. The purpose of this study is to
examine relationships between waterfowl and SAV resources of the Bay.
Specific objectives include an examination of 1) waterfowl food
-------
habits in the Bay area, 2) distribution and abundance of SAV, 3) winter-
ing waterfowl populations, 4) relationships between waterfowl and the
distribution and abundance of SAV, and 5) impacts of waterfowl on SAV.
3
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SECTION 2
CONCLUSIONS
Historically, Maryland waterfowl populations were more diverse in
species and more numerous than those in Virginia, where populations were
generally more stable. Distributions (dispersions) of species
populations among survey areas in both States were remarkably stable.
The most important wintering areas for waterfowl in Chesapeake Bay are
the Chester River, Eastern Bay, and the lower Choptank River.
Significant changes occurred in the Bay's submerged aquatic plant
resources during the 1970's. SAV abundance declined considerably from
1971 to 1973, and fluctuated thereafter. Of the seven plants examined,
widgeongrass (Ruppia maritima) was the most widely distributed (number
of areas) and abundant (highest frequency occurrence) species of SAV in
Maryland. However, all species declined during the 1971-79 period. SAV
in Maryland was most abundant in the lower Choptank River, Manokin and
Annemessex Rivers area, Chester River, and Eastern Bay.
Species of waterfowl adapted differently to these conditions.
Increased numbers of whistling swans began feeding in agricultural
fields during the early 1970's, even though this behavior was well
established 10-15 years earlier on their northward migrations.
Responses among ducks were affected by physical differences between the
two general categories examined. Puddle or dabbling ducks, which
normally feed by tipping up in shallow water, are capable of feeding in
agricultural fields and dense marsh habitats. Diving or bay ducks have
evolved relatively shorter wings and other physical characteristics that
facilitate swimming beneath the water's surface where they typically
feed. These birds, essentially incapable of feeding on land, could
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change their food preferences only within the estuarine environment. Of
course, both puddle and diving ducks could winter elsewhere within or
outside of the Bay area.
Maryland populations of the four puddle duck species examined were
considerably less abundant during the 1970's when compared to long-term
levels. Pintail (Anas acuta) and American wigeon (A. americana)
populations, which have known preferences for SAV, are now essentially
absent from Maryland wintering areas. Black duck and mallard
populations, which showed relationships to the distribution and
abundance of SAV, also decreased. The current level of Maryland puddle
duck populations, as a group, is about one-third of the former level.
Among diving ducks, canvasbacks and redheads (Aythya americana)
were most affected by the recent decline in SAV. Although species of
SAV were principal food items of canvasbacks prior to the 1970's, they
were essentially the only foods of redheads. Canvasback food
preferences completely changed during the 1970's to a diet that
consisted mainly of Baltic macoma clams (Macoma balthica) and other
invertebrates. Also during that period, Maryland wintered a decreasing
percentage of the Atlantic Flyway canvasback population. Although
significant changes in the Flyway distribution of redheads occurred
prior to the 1970's, the most important difference was a consistently
low number of these birds throughout the 1970's. The redhead population
in Maryland is now only a remnant of past populations.
On the positive side, the Canada goose population in Maryland
continued to expand. These birds began foraging on land during the mid-
1950's when the mechanization of agriculture increased the availability
of waste (unharvested) cereal grains. This population averaged about
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265,000 geese between 1956 and 1971, although it increased at a rate of
23,000 birds/year. During recent years Maryland wintered more than
500,000 Canada geese. The future of this population rests in
agricultural fields.
Waterfowl populations have had no long-term impact on distribution
and abundance of SAV. Prior to the 1970's, waterfowl populations were
greatest in areas such as Chester River, Eastern Bay, arid the lower
Choptank River. During the 1970's, SAV was most abundant in these areas
despite a history of use by abundant waterfowl populations.
The relatively low diversity of waterfowl species currently
wintering in Maryland, although mitigated somewhat by tremendous
populations of Canada geese, is cause for concern. However, the outlook
is optimistic due in large measure to the northern location of
Chesapeake Bay with respect to other important wintering areas. Major
population segments of most Flyway species annually stop in the Bay area
while on migration to and from wintering areas farther south. These
populations are therefore exposed to Bay conditions on an annual basis.
We anticipate they would soon respond positively to an improvement in
distribution and abundance of submerged aquatic vegetation.
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SECTION 3
MATERIALS AND METHODS
SOURCES AND LIMITATIONS OF DATA
Waterfowl Food Habits
Food habits of Chesapeake Bay waterfowl were summarized by Stewart
(1962). His original data, collected mostly during the 1950's, were
obtained and supplemented with additional samples for some species.
Although methods and specific areas of collection were identifiable for
most samples, these potentially important sources of variation were
disregarded to increase sample sizes and provide a Bay-wide description
of food items used by waterfowl. Other sources of variation, such as
the organ from which foods were obtained and identified (Swanson and
Bartonek 1970), temporal or long-term changes (Perry and Uhler 1976),
and differences between species (Stewart 1962) were included.
Stewart (1962:2) determined the total volume of food contents for
an organ sample by volumetric displacement, and then visually estimated
the proportion of each food item. Samples from other collections
differed only in that volumes for each food item were separately
measured, or that organ (source) was not recorded. Scientific and
common names of Bay.waterfowl food items are shown in Appendix Table A-l•
Various measures have been used to describe the food habits of
animals (e.g., Martin et al. 1946; Korschgen 1969; Swanson et al« 1974).
The latter authors demonstrated that the aggregate percent method was
favored over the aggregate volume method. Briefly, if we have J food
items and I birds, the aggregate percentage is the proportion of the jth
food item in the ith bird averaged over all samples. This procedure
gives equal weight to each bird in the sample, and is not affected by
7
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variation in individual sample volumes (Swanson et al. 1974:303); this
is particularly appropriate here since most samples were opportun-
istically obtained. In addition to aggregate percentages, we also
determined the frequency occurrence of each food item in the sample.
Since we have no measures of availability for many food items used
by Bay waterfowl, we must exercise caution when discussing preference,
selection, or importance. We are consequently limited in the questions
or hypotheses we may examine with these data. Johnson (1980) discussed
these problems and proposed a procedure for comparing ranks of usage and
availability measurements. Johnson's method basically compares two
multivariate normal vectors of means (ranks), and is sufficiently
general for our purposes. Here we are interested in the hypothesis of
no difference between two samples in utilization of important food
items. Our application of Johnson's method therefore compares two
levels of usage rather than usage and availability.
In a preliminary series of analyses we were interested in whether
or not samples of food items identified in two different organs were
sufficiently similar to allow combination. In practice, we identified a
small list (i.e., the number of items was small compared to available
sample sizes) of items that were important (frequently utilized) in
samples from organ A. We then determined the rank of each food item on
the list with respect to the other listed items for each individual in
both organ samples A and B. Mean ranks of usage for each food item
within each category (organ) were then computed and compared through a
multivariate analysis of variance. We used this approach for all
comparative food habits analyses.
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Waterfowl Populations
The U.S. Fish and Wildlife Service (USFWS) in cooperation with the
States conducts annual surveys of wintering waterfowl during January,
when population distributions are most stable and perhaps most
concentrated. According to Benning et al. (1978:1), "This survey
primarily monitors annual changes in waterfowl distribution on the
wintering grounds within the United States, and indicates annual
population trends". Although survey results are affected by such
factors as weather, personnel changes, and errors of omission (birds not
found) and commission (birds found but counted inaccurately), they
constitute the only long-term source of information on the distribution
and abundance of wintering waterfowl. Most states have developed
systems of survey areas which generally encompass rivers, bays, or large
expanses of marsh habitat. Survey area boundaries were stable in
Maryland (Figure 1) by 1956 and in Virginia (Figure 2) by 1961.
Waterfowl surveys in the Potomac River, ocean bays, and inland
reservoirs and swamps were not included in analyses of species
distributions among survey areas, since comparable data on submerged
aquatic vegetation were not available. Some waterfowl species (e.g.,
Atlantic brant, greater snow goose [Anser caerulescens atlantica])»
whose populations were generally restricted to those habitats, were
consequently omitted. An index to waterfowl survey areas used in this
study is provided in Table 1.
The Atlantic Flyway, which encompasses Atlantic coastal States from
Maine to Florida, is one of four U.S. flyways used in the management of
waterfowl populations. United States and Atlantic Flyway populations
can be used as measures of general abundance or trend that may affect
-------
Figure 1. Maryland waterfowl survey areas used in this report.
10
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Figure 2. Virginia waterfowl survey areas used in this report.
11
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TABLE 1. INDEX TO WATERFOWL SURVEY AREAS3 IN MARYLAND AND VIRGINIA
Number
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
20
21
25
26
27
28
29
Mar
Size (ha)b
17,227
8,076
4,528
1,648
2,444
7,791
2,214
4,502
4,484
7,953
1,775
2,073
2, 159
13, 159
2,758
7,566
7,515
5,665
6,896
6,247
7,366
11,446
13,816
4,265
y 1 a n d
Survey area name
Patapsco River - Aberdeen P.G.
Susquehanna Flats
Northeast - Elk - Bohemia Rivers
Sassafras River
Bayshore, Kent County
Chester River
Bayshore, Kent Island
Magothy - Severn Rivers
South River - Herring Bay
Eastern Bay
Wye River
Upper Choptank River
Mi les Ri ver
Lower Choptank River
Bayshore, Calvert County
Patuxent River
Little Choptank River
Bayshore, Hooper Island
Honga River
Fishing Bay
Nanticoke - Wicomico Rivers
Bloodsworth - South Marsh Islands
Manokin, Big - Little Annemessex R.
Smith Island
V
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
18
19
20
i r g i n i a
Survey area name
James River (Lower)
James River (Middle)
James River (Hog Island Refuge)
James River (Upper)
James River (Presquile NWR)
Chickahominy River
Pamunkey River
Mattaponi River
York River
Mobjack Bay and Piankatank River
Rappahannock River (Lower)
Rappahannock River (Upper)
Smith Pt. - Windmill Pt.
Fisherman's Island - Silver Beach
Silver Beach - Saxis
Newport News - York River
Maryland survey areas are shown in Figure 1, and those in Virginia are shown in Figure 2. Areas beyond
the scope of this study (e.g., inland reservoirs, ocean bays) are not listed.
Size equals the extent of shoal water habitat «2.44^m at mlw) in a survey area.
-------
Chesapeake Bay numbers of ducks, geese, or swans. We can also use these
data to identify species that have a tradition of wintering in the Bay.
Since waterfowl populations and habitats in Maryland and Virginia
portions of the Bay are considerably different, we will consider
populations in these areas separately.
We used mid-winter survey results prior to 1972 as measures of
long-term distribution and abundance of United States, Atlantic Flyway,
and Maryland and Virginia wintering waterfowl populations. We first
identified waterfowl species whose Bay populations averaged five percent
or more of Atlantic Flyway populations prior to 1972. Species that did
not meet this criterion were subsequently omitted. For the remaining
species we then examined population segments (survey areas, Flyway, and
U.S.) for trends in distribution or abundance prior to the early 1970's.
We used survey results during the years 1972-80 to describe current Bay
waterfowl resources in a similar manner. Comparisons could then be made
between waterfowl populations during the long-term and current periods,
and between current waterfowl and SAV distribution and abundance.
Submerged Aquatic Vegetation
Stevenson and Confer (1978) summarized available information on the
distribution and abundance of submerged aquatic vegetation (SAV) in
Chesapeake Bay. Bayley et al. (1978) described long-term (1958-1975)
changes in SAV at the head of the Bay (Susquehanna Flats), and Orth et
al. (1979) documented the distribution and abundance of SAV in Virginia
waters during the 1970's (1971,1974, and 1978). Kerwin et al. (1976)
initiated an extensive (Maryland) and long-term (1971-) survey of SAV
with which .the distribution and abundance of waterfowl could be
compared. Kerwin's study, which evolved into a cooperative effort
13
-------
between the USFWS Migratory Bird and Habitat Research Laboratory (MBHRL)
and the Wildlife Administration of Maryland Department of Natural
Resources (DNR), was based on a stratified random sampling (about 640
stations) of shoal water habitats (<2.44 m at mean low water) in
Maryland (excluding the Potomac River). To monitor annual trends in
distribution and abundance of SAV, established stations were sampled
once each summer for presence/absence and percent composition of SAV.
Procedures are further described in Kerwin et al. (1976).
Since waterfowl survey area boundaries did not correspond to those
of the SAV survey, we examined latitude-longitude coordinates of sample
stations in the SAV survey to resolve boundary discrepancies. We were
then able to measure (planimeter) the extent of shoal water habitat in
24 waterfowl survey areas and summarize SAV survey results accordingly.
We estimated hectares of SAV in an area by multiplying the size of the
area by the proportion of stations sampled that were vegetated. These
estimates of SAV are biased upwards due to the inherent assumption of
complete coverage (dense bed) at a vegetated station. Use of these
estimates to represent distribution and abundance of SAV during winter
is another limitation.
STATISTICAL ANALYSES
Analyses of variance and linear regression used in this report
followed the Statistical Analysis System user's guide (Barr et al.
1976). We generally used the simplest (fewest parameters) linear model
that adequately described the relationship between a dependent and one
or more independent variables. Where appropriate, area-specific effects
ere included if they were significant (p < 0.05). In models with more
than one independent variable, we used sums of squares and .corresponding
14
-------
F statistics that reflected adjustments for all other variables in the
model.
Given annual estimates of SAV (summer in year t-1) and waterfowl
(January in year t) in a number of survey areas, we were then able to
formulate the following linear model:
n .. = A + B (SAV .) + C (ATL ) ,
a,t a a,t-1 a t
where n is the predicted number of birds in survey area a, A is an
a,t
overall intercept term, B. is the area-specific effect of SAV, SAV
3. €*9 L"" J.
is the number of hectares of SAV in area a during the previous summer,
C is the area-specific effect of general species abundance, and ATL is
3. t
the Atlantic Flyway population during the current year t. The intercept
term was included to determine if a significant portion of an area's
population was independent of variation in SAV or general species
abundance. The Atlantic Flyway population was included to measure the
extent to which changes in an area's population merely reflected annual
variation in the size of the general population. If an effect was not
significant (p > 0.05), it was removed and a reduced model was then
considered for that species.
15
-------
SECTION 4
RESULTS AND DISCUSSION
WATERFOWL FOOD HABITS
A study of waterfowl food habits is a study of variability, some of
which (e.g., areas and methods of collection) is unavoidable. More than
3,000 food habits records accumulated by Stewart (1962), Rawls (in
prep.), and data from the files (MBHRL, Laurel, Maryland) included about
700 different food items (Appendix A). These data were tabulated by
waterfowl species, time period (pre-1960, 1960's, and the 1970's in
Appendices B, C, and D), and organ source (gizzard, gullet, or unknown).
Preliminary analyses using Johnson's (1980) methodology indicated
there were substantial differences in usage (aggregate percentages) of
food items in samples from different organs. Since this variation
persisted across a number of waterfowl species, we restricted food
habits comparisons to those species for which sufficient gizzard samples
were available. We also were unable to' statistically compare 1960's
food habits data (Rawls, in prep.) with those from earlier or later
periods, since we lacked data from individual samples.
A gross comparison of the incidence of plant material in samples of
Bay waterfowl (Table 2) revealed only a few differences across three
time periods. Based on aggregate percentages described earlier, usage
of plant material by canvasbacks decreased from 71 to about 9 percent.
A smaller decrease was also suggested for the common goldeneye
(Bucephala clangula americana). Since other apparent changes were
minor, the incidence of plant material in samples of Chesapeake Bay
waterfowl has not considerably changed during the 1960's or 1970's.
There were exceptions to the general importance of vegetation to
16
-------
TABLE 2. SUMMARY OF THE INCIDENCE OF PLANT MATERIAL IN THE DIET OF
WATERFOWL THAT WINTER IN CHESAPEAKE BAY
Percent plant materi
Species
Whistling swan
Canada goose
Ruddy duck
Bufflehead
Common goldeneye
Canvasback
Greater scaup
Lesser scaup
Ring-necked duck
Redhead
American wigeon
Blue-winged teal
Green-winged teal
Black duck
Gadwall
Mallard
Pintail
Pre-1960
74
65
24
53
71
40
51
65
99
97
90
84
74
99
98
97
.7
.2
.6
. 1
.3
.4
.4
.4
.0
. 1
.7
.9
. 1
.0
.9
.5
( 50)b
( 25)
( 20) b
( 14)
( 47)
( 36)
( 29)
( 17)
( 86) b
( 35)
( 21)
( 10)
( 55)
( 21) b
( 25)
( 36) b
100.
-
32.
36.
52.
37.
56.
94.
76.
97.
-
100.
93.
-
94.
96.
air and sample size ( ) «
1960's
0
6
9
3
2
7
0
6
7
0
5
5
4
(221)
( -)
( 27)
( 45)
(246)
( 9)
( 82)
( 10)
( 77)
(121)
( -)
( 13)
(131)
( -)
(134)
( 47)
-
20.
25.
8.
32.
57.
-
96.
-
-
91.
82.
-
92.
95.
1970'
8
1
6
8
9
6
3
6
7
2
(
(
(
(
s
_}
-)
30)
21)
(273)
(
(
(
(
<
c
(
(
(
(
(
40)
76)
-)
7)
-)
-)
29)
57)
-)
84)
27)
Summarized from tables in Appendices B, C, and D. Unless otherwise
noted, aggregate percentages are those from gizzard samples.
Aggregate percentages are those from samples for which organs Mere
not recorded.
-------
puddle ducks and animal material to diving ducks. The diet of the black
duck, a common puddle duck in the Bay, included perhaps 25 percent
animal material whereas the redhead, a diving duck, fed almost
exclusively on vegetation.
There were only a few species for which adequate samples were
available from the pre-1960 (historic) and 1970's (current) periods. We
were able to compare usage of important food items within periods for
two puddle ducks (black duck and mallard) and two diving ducks
(canvasback and lesser scaup [Aythya affinis]). For each of these
species we listed the most important food items found in samples of
these birds during the historic period (Appendix B). We then compared
relative importance of listed food items during historic and current
periods by testing the following null hypothesis: usage of historically
important food items by the species has not changed.
Food items of historic importance to black ducks ranged from the
intertidal salt marsh snail (Melampus bidentatus) to emergent marsh
plants like twig-rush (Cladium mariscoides) and dotted smartweed
(Polygonum punctatum) of fresh coastal areas (Table 3). Widgeongrass
was the only SAV species considered important to black ducks during that
period; utilization of widgeongrass, based on relative importance of the
other food items examined, has not recently changed. Although the
overall comparison indicated significant differences, recent changes in
relative importance were restricted to emergent marsh plants.
Unlike black ducks, mallards are much more oriented to plant
material including emergent plants of marshes, corn (Zea mays) of
agricultural origin, and widgeongrass of shallow waters (Table A). The
relative importance of widgeongrass was again similar (as in black
18
-------
VO
TABLE 3. RESULTS OF TESTING THE HYPOTHESIS THAT USAGE OF HISTORICALLY
IMPORTANT FOOD ITEMS BY BLACK DUCKS HAS NOT CHANGED
Important food items
Current
use b
Melampus bidentatus
Cyprinodon variegatus
Fundulus heteroclites
Ruppia maritima
Cladium mariscoides
Scirpus Olneyi
Zizania aquatica
Polygonum punctatum
salt marsh snai1
sheepshead minnow
MIdgeongrass
twi g-rush
olney threesquare
wildrice •
dotted smartweed
Overall comparison: F(8,80) = 5.75, p>F =
less
less
more
0.000 1C
almportant food items were identified on the basis of aggregate
percentages (Appendix B).
Current use, if significantly different (0.05 level), is either more
or less during the 1970's than during the historic (pre-1960) period.
Q
We reject the hypothesis of no change, due to the highly significant
test statistic for the overall comparison.
-------
TABLE 4. RESULTS OF TESTING THE HYPOTHESIS THAT USAGE OF HISTORICALLY
IMPORTANT FOOD ITEMS BY MALLARDS HAS NOT CHANGED
S3
O
p o r t a n t food items
a
Current
US6b
Ruppia maritima
Cyperaceae
Scirpus spp.
Gramineae
Zea mays
Polygonum spp.
widgeongrass
sedge
bulrush
grasses
corn
smartweed
Overall comparison: F(6,42)
less
more
= 3.63, p>F = 0.0055 c
Important food items were identified on the basis of aggregate
percentages (Appendix B).
Current use, if significantly different (0.05 level), is either more
or less during the 1970's than during the historic (pre-1960) period.
cWe reject the hypothesis of no change, due to the highly significant
test statistic for the overall comparison.
-------
ducks) during both periods, even though the overall comparison suggested
recent changes for other items. The significantly higher rank of corn
during the current period suggests an increase in the incidence of field
feeding by mallards.
Although canvasbacks have always eaten invertebrates such as
gastropod and pelecypod mollusks, they are best known as feeders on SAV,
particularly wildcelery (Table 5). Of. three SAV species compared, two
decreased in relative importance during the current period. Decreases
were also found in current use of some invertebrates, even though there
was a substantial increase in the importance of the Baltic macoma clam.
Small size classes (<25 mm) of these clams have recently become very
important, as they were found in 93 percent of 273 gizzard samples
(Appendix Table D-3). Extensive use of these clams by individual
canvasbacks was also indicated since the aggregate percentage, which
measures percentage by volume, averaged 84 percent.
Samples from lesser scaup, another diving duck, were similarly
analyzed (Table 6). Current uses (ranks) of widgeongrass, redhead grass
(Potamogeton perfoliatus), and wildcelery, all of which were
historically important SAV species, are relatively similar. Gastropods
contributed most to the overall difference in relative importance among
the food items examined.
Since current use was compared to historic use, any items that are
important now, but not historically, are not included here in comparative
food habits analyses. Although diversity of food items currently
available is undoubtedly less, there have been relatively recent
additions to the Bay's flora and fauna. Springer and Stewart (1959)
reported that by the late 1950's Eurasian watermilfoil (Myriophyllum
21
-------
TABLE 5. RESULTS OF TESTING THE HYPOTHESIS THAT USAGE OF HISTORICALLY
IMPORTANT FOOD ITEMS BY CANVASBACKS HAS NOT CHANGED
to
NJ
Important food
Molluscs
Pelecypoda (Bivalvia)
Macoma balthica
Polychaeta
Potamogeton pectinatus
Potamogeton perfoliatus
i t e m s a
mollusk
bi valve
Baltic tnacoma
polychaete
sago pondweed
redhead grass
Current
use "
less
less
more
less
less
Vallisneria americana (spiralis) wildcelery less
Zea mays corn
Overall comparison: F(8,298) = 94.79, p>F = 0.0001C
^Important food items were identified on the basis of aggregate
percentages (Appendix B).
^Current use, if significantly different (0.05 level), is either more
or less during the 1970's than during the historic (pre-1960) period.
cWe reject the hypothesis of no change, due to the highly significant
test statistic for the overall comparison.
-------
TABLE 6. RESULTS OF TESTING THE HYPOTHESIS THAT USAGE OF HISTORICALLY
IMPORTANT FOOD ITEMS BY LESSER SCAUP HAS NOT CHANGED
NJ
CO
Important food
Gastropoda
Goniobasis virginica
Gillia altilis
Amnicola spp.
Ruppia maritima
Potamogeton perfoliatus
Vallisneria americana (spiralis)
Overall compari
i t e m sa
snai 1 , limpet
snai 1
snai 1
amni cola
wi dgeongrass
redhead grass
wi Idcelery
son: F(7,67) =
Current
useb
less
less
10.21, p>F = 0.0001 c
almportant food items were identified on the basis of aggregate
percentages (Appendix B).
Current use, if significantly different (0.05 level), is either more
or less during the 1970's than during the historic (pre-1960) period.
cWe reject the hypothesis of no change, due to the highly significant
test statistic for the overall comparison.
-------
spicatum) had become well established on the Susquehanna Flats at the
head of Chesapeake Bay, an area famous for waterfowl concentrations
during fall months. Prior to 1960, milfoil was found only in samples of
ruddy ducks (Oxyura .lamaicensis, Appendix Table B-2), green-winged teal
(Anas crecca. Appendix Table B-12), and gadwalls (A. strepera, Appendix
Table B-14). During the 1960's, however, Rawls (in prep.) found milfoil
in 13 species of waterfowl (Appendix C) including American wigeon, for
which milfoil was very important (Appendix Table C-9). Milfoil is
currently not utilized by waterfowl except in small amounts by a few
individuals.
The brackish water clam (Rangia cuneata) is another recent member
of the Bay's community (Pfitzenmeyer and Drobek 1964). This clam was
not found in any samples of Bay waterfowl collected prior to 1960, but
it has become increasingly important to diving ducks through the 1960's
and into the current period.
Based on summaries of waterfowl food habits of 12 species, we
conclude that except for the canvasback there have been few important
changes in the incidence of plant material in samples of Chesapeake Bay
waterfowl. Although current use of historically important food items
was significantly different within each of four waterfowl species
examined, changes in relative importance of invertebrates and emergent
marsh plants contributed substantially to those differences. We
conclude further that canvasbacks are adaptable diving ducks, since
clams have become very important Bay food resources for these birds.
This adaptation was most likely caused by recent declines in
distribution and abundance of SAV.
Whistling swans apparently adapted to changing Bay conditions in
24
-------
another manner. Prior to 1970 few swans fed in agricultural fields
while wintering in Maryland, even though this behavior was well
established by swans while migrating during spring. Then during the
late winter of 1969-70 significant numbers of swans began feeding in
agricultural fields (principally corn and other cereal grains) following
six weeks of freezing weather (V. D. Stotts, personal communication),
which froze over much of the shoal water habitat in the upper Bay.
Although this provided the initial stimulus, more and more swans began
feeding in fields early (November) during subsequent winters when SAV
was known to have declined. Field feeding by swans wintering in
Maryland and other Flyway wintering areas has persisted to date (Munro,
in prep.) .
DISTRIBUTION AND ABUNDANCE OF SAV
We first considered SAV without regard to species (Table 7). SAV
declined considerably during the early 1970's. From a high of 28.7
percent.during 1971, frequency occurrence of vegetated sample stations
in Maryland waters declined to 21.0 percent the following summer (after
Tropical Storm Agnes). Frequency occurrence declined further during
1973 to 10.5 percent and has essentially fluctuated between 8-15 percent
thereafter. Orth et al- (1979), in their study of the distribution and
abundance of SAV in Virginia waters, also found a precipitous decline in
SAV during the 1970"s. Similarly, little SAV was found during the late
1970's in the Potomac River (Carter and Haramis 1980), largest of the
Bay's numerous estuaries.
Based on nine-year averages, the lower Choptank River was the most
important area in the Chesapeake Bay for SAV during the 1970's. One of
the largest areas, the lower Choptank has consistently produced the most
25
-------
TABLE 7. FREQUENCY OCCURRENCE OF SAV (SPECIES COMBINED) IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-19793
Survey area
Lower Chop-tank River
Manokin, Annemessex R.
Chester River
Eastern Bay
Smith Island (Maryland)
Bloodsworth, South Marsh I.
Honga River
Patapsco R., Aberdeen P.G.
Susquehanna Flats
Bayshore, Hooper Island
Magothy - Severn Rivers
Mi les Ri ver
Wye River
Little Choptank River
Patuxent River
Upper Choptank River
Fishing Bay
Sassafras River
South River, Herring Bay
Northeast, Elk, Bohemia R.
Bayshore, Kent County
Bayshore, Ken-t Island
Total
1 9
37.3
42. 1
61.1
32. 1
64.7
40.0
50.0
7.7
54.5
65.2
37.0
50.0
27.3
13.3
2.0
22.2
8.0
30.0
0.0
5.0
16.7
0.0
28.7
P e
7 1
(51)
(57)
(36)
(28)
( 17)
(40)
(30)
(52)
(22)
(23)
(27)
( 8)
(11)
(30)
(50)
( 9)
(25)
(10)
(21)
(20)
(12)
( 8)
(624)
r c e
1 9
43.8
38.2
36. 1
45.8
45.5
22.7
40.0
4.0
3.3
52.2
11.1
50.0
45.5
13.3
4.4
20.0
4.0
0.0
0.0
0.0
0.0
0.0
21.0
n t
7 2
(48)
(55)
(36)
(24)
(11)
(44)
(30)
(50)
(30)
(23)
(27)
( 8)
(11)
(30)
(45)
(10)
(25)
( 10)
(21)
(23)
( 6)
( 8)
(613)
w i •
1 9
23.4
16. 1
26.5
25.0
25.0
10.9
13.3
4.0
0.0
4.3
22.2
50.0
45.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
10.5
t h
7 3
(47)
(56)
(34)
(28)
(12)
(46)
(30)
(50)
(30)
(23)
(27)
( 8)
(11)
(30)
(50)
(10)
(25)
(10)
(21)
(23)
(12)
( 8)
(629)
v e g
1 9
30.6
41.2
23.5
25.0
35.3
11.6
16.7
5.8
16.7
8.7
22.2
50.0
54.5
0.0
4.0
11.1
0.0
10.0
0.0
0.0
0.0
12.5
14.9
eta
7 «
(49)
(34)
(34)
(28)
(17)
(43)
(30)
(52)
(30)
(23)
(27)
( 8)
(11)
(30)
(50)
( 9)
(25)
( 10)
(19)
(23)
(12)
( 8)
(610)
t i (
1 9
2. 1
19.2
25.0
18.5
23.5
7.0
10.3
9. 1
13.3
8.7
B
25.0
27.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
8.7
on,
7 5
(47)
(52)
(36)
(27)
(17)
(43)
(29)
(22)
(30)
(23)
( 0)
( 8)
(11)
(30)
(47)
(10)
(24)
(10)
( 14)
(22)
(12)
( 8)
(552)
a n
1 9
50.0
15.8
25.7
40.7
35.3
2.2
17.2
5.8
10.3
13.0
32.0
42.9
45.5
10.0
2.0
0.0
0.0
0.0
4.8
0.0
0.0
0.0
15.0
d s
7 6
(46)
(57)
(35)
(27)
(17)
(45)
(29)
(52)
(29)
(23)
(25)
( 7)
(11)
(30)
(49)
(10)
(25)
(10)
(21)
(22)
(12)
( 8)
(628)
a m |
1 9
30.6
19.6
36. 1
22.2
23.5
4.3
3.3
11.5
13.3
4.3
22.2
50.0
27.3
6.7
2.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
12.4
ale
7 7
(49)
(56)
(36)
(27)
(17)
(46)
(30)
(52)
(30)
(23)
(27)
( 8)
(11)
(30)
(49)
(10)
(25)
(10)
(21)
(23)
(12)
( 8)
(638)
s i
1 9
34.7
10.9
44.4
14.8
5.9
0.0
3.3
5.8
3.4
0.0
18.5
50.0
36.4
3.3
2.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
10. 1
z e
7 8
(49)
(55)
(36)
(27)
(17)
(46)
(30)
(52)
(29)
(23)
(27)
( 8)
(11)
(30)
(50)
(10)
(25)
( 10)
(21)
(22)
(12)
( 8)
(636)
( )
1 9
29.8
0.0
33.3
14.8
17.6
0.0
0.0
7.7
6.9
0.0
18.5
0.0
18.2
3.3
2. 1
0.0
0.0
0.0
4.8
4.3
0.0
0.0
7.9
7 9
(47)
(56)
(36)
(27)
(17)
(45)
(30)
(52)
(29)
(23)
(27)
( 8)
(11)
(30)
(48)
(10)
(24)
(10)
(21)
(23)
(12)
( 8)
(631)
aData from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the extent of shoal habitat (<2.44 m at mlw) in an area,
determined -the sequence of survey areas used above.
-------
SAV except during 1975 when abundance was extremely low. Another large
area, which includes the Manokin, Big and Little Annemessex Rivers, and
a portion of Pocomoke Sound, ranked second> Vegetation in this area
declined after 1974 and was not found at all during the 1979 sampling.
Among the most stable areas in the Bay for SAV are the Chester River and
Eastern Bay.
The exposed bayshores, such as those along Kent County and Kent
Island, are among the least vegetated shoal water habitats. Similarly,
sample stations along the Calvert County Bayshore (not listed) have not
yielded SAV during the 1970's, according to this survey.
Another overview of SAV distribution and abundance is provided in
Table 8, where frequency occurrence is based on the presence of
vegetation in measurable amounts (see Kerwin et al. 1976). Ranks of
survey areas, based on average SAV abundance, are similar to those shown
in Table 7, although the distribution of SAV (the number of areas
listed) is reduced. Frequency occurrence of SAV during the nine-year
period followed the same downward trend, but at a reduced scale.
Widgeongrass was the most abundant and widely distributed species
of SAV during all nine years (Appendix Table E-l). Found in almost all
Bay tributaries due to its wide salinity tolerance, widgeongrass was the
most important food item for American wigeon historically (Appendix
Table B-10) as well as during the 1960's (Appendix Table C-9). This
species of SAV, which was also the most important food item for black
ducks, is currently used to some extent by all waterfowl species
examined except for the green-winged teal.
Widgeongrass is obviously very important to Bay waterfowl, but it
may also comprise nearly 50 percent of all the SAV in Maryland waters;
27
-------
TABLE 8. FREQUENCY OCCURRENCE OF MEASURABLE SAV (SPECIES COMBINED) IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-7$
Survey area "
Lower Choptank River
Manokin, Annemessex R.
Chester River
Eastern Bay
Smith Island (Maryland)
Bloodsworth, South Marsh I.
Patapsco R., Aberdeen P.O.
Honga River
Bayshore, Hooper Island
Magothy - Severn Rivers
Susquehanna Flats
Mi les Ri ver
Wye River
Little Choptank River
Upper Choptank River
Fi shi ng Bay
Sassafras River
Northeast, Elk, Bohemia R.
Bayshore, Kent County
Patuxent River
Total
1 9
25.5
33.3
41.7
21.4
47. 1
27.5
1.9
30.0
39. 1
33.3
36.4
12.5
9. 1
10.0
11.1
8.0
20.0
5.0
8.3
0.0
19.2
P e i
7 1
(51)
(57)
(36)
(28)
(17)
(40)
(52)
(30)
(23)
(27)
(22)
( 8)
(11)
(30)
( 9)
(25)
(10)
(20)
(12)
(50)
(624)
r c e
1 9
20.8
12.7
13.9
20.8
27.3
13.6
0.0
23.3
17.4
7.4
0.0
37.5
36.4
3.3
20.0
0.0
0.0
0.0
0.0
0.0
9.6
n t
7 2
(48)
(55)
(36)
(24)
(11)
(44)
(50)
(30)
(23)
(27)
(30)
( 8)
(11)
(30)
(10)
(25)
(10)
(23)
( 6)
(45)
(613)
M i -I
1 9
14.9
10.7
14.7
14.3
25.0
8.7
2.0
3.3
4.3
14.8
0.0
12.5
18.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
6.2
b h
7 3
(47)
(56)
(34)
(28)
(12)
(46)
(50)
(30)
(23)
(27)
(30)
( 8)
(11)
(30)
(10)
(25)
( 10)
(23)
(12)
(50)
(629)
v e g
1 9
14.3
17.6
11.8
10.7
23.5
7.0
3.8
3.3
8.7
14.8
6.7
12.5
36.4
0.0
0.0
0.0
0.0
0.0
0.0
2.0
7.2
eta
.7 4
(49)
(34)
(34)
(28)
(17)
(43)
(52)
(30)
(23)
(27)
(30)
( 8)
(11)
(30)
( 9)
(25)
(10)
(23)
(12)
(50)
(610)
t i (
1 9
0.0
5.8
11.1
14.8
11.8
0.0
4.5
3.4
4.3
m
6.7
25.0
9. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
3.8
3 n ,
7 5
(47)
(52)
(36)
(27)
(17)
(43)
(22)
(29)
(23)
( 0)
(30)
( 8)
(11)
(30)
(10)
(24)
(10)
(22)
(12)
(47)
(552)
a n
1 9
21.7
14.0
8.6
18.5
17.6
0.0
1.9
3.4
4.3
0.0
0.0
28.6
18.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
5.7
d s
7 6
(46)
(57)
(35)
(27)
(17)
(45)
(52)
(29)
(23)
(25)
(29)
( 7)
(11)
(30)
( 10)
(25)
(10)
(22)
( 12)
(49)
(628)
a m |
1 9
8.2
12.5
16.7
14.8
0.0
0.0
7.7
0.0
4.3
7.4
0.0
25.0
9. 1
3.3
0.0
0.0
0.0
0.0
0.0
0.0
5.0
D 1 e
7 7
(49)
(56)
(36)
(27)
(17)
(46)
(52)
(30)
(23)
(27)
(30)
( 8)
(11)
(30)
(10)
(25)
(10)
(23)
(12)
(49)
(638)
s i
1 9
6. 1
0.0
30.6
11.1
5.9
0.0
3.8
3.3
0.0
11.1
0.0
12.5
9. 1
3.3
0.0
0.0
0.0
0.0
0.0
0.0
4.2
z e
7 8
(49)
(55)
(36)
(27)
(17)
(46)
(52)
(30)
(23)
(27)
(29)
( 8)
(11)
(30)
(10)
(25)
( 10)
(22)
(12)
(50)
(636)
( )
1 9
12.8
0.0
22.2
11.1
5.9
0.0
5.8
0.0
0.0
14.8
6.9
0.0
9. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
4.4
79
(47)
(56)
(36)
(27)
(17)
(45)
(52)
(30)
(23)
(27)
(29)
( 8)
(11)
(30)
( 10)
(24)
(10)
(23)
(12)
(48)
(631)
aData from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the extent of shoal habitat (<2.44 m at mlw) in an area,
determined the sequence of survey areas used above.
-------
it certainly is the predominant species of SAV in Maryland's mesohaline
(5-18 ppt) waters. Orth et al. (1979) found that eelgrass (Zostera
marina) and widgeongrass were the most abundant SAV species in
mesohaline and polyhaline (18-30 ppt) waters of Virginia.
Eelgrass was the second most abundant species during most years
(Appendix Table E-2). Eelgrass was found in waters of higher salinity
(>7 ppt), but as far north as Eastern Bay. Abundance of eelgrass, like
other SAV species, declined considerably from 1972 to 1973- Although
this species was found at 65 sample stations in Maryland waters during
1971, it was essentially absent (1 station) during 1979-
Eelgrass was not an important food resource for Bay waterfowl
although it was found in small amounts in 11 of 16 species examined
(Appendix B). This species was the principal food of the Atlantic brant
prior to the wasting disease of the early 1930's, when eelgrass and
brant populations plummeted (Lincoln 1950). These birds subsequently
used sea lettuce (Ulva lactuca) as their principal food while wintering
in Atlantic coastal areas. Sea lettuce, a marine alga found commonly in
ocean bays and occasionally in Maryland waters (>7 ppt), is still the
primary food of wintering brant (Penkala 1975).
Redhead grass was not an important waterfowl food, although small
amounts of this item were found in 15 of 16 species examined (Appendix
B). The distribution of redhead grass was restricted to only seven
survey areas (Appendix Table E-3). Abundance of this species is
greatest in the Chester River and Eastern Bay, both of which are among
the most important waterfowl wintering areas.
Sago pondweed (Potamogeton pectinatus), historically important to
canvasbacks (Appendix Table B-5) and redheads (Appendix Table B-9), is
29
-------
more widely distributed (Appendix Table E-4) but usually less abundant
than redhead grass. Unlike other SAV species discussed previously, sago
pondweed was infrequently found when this survey began in 1971. It was
also uncommon during subsequent years-
Eurasian watermilfoil was a very abundant species during the early
1960's (Bayley et al. 1978). Although known to have displaced other
SAV species during its peak in 1963 (Elser 1967), it was an uncommon
plant during the 1970's (Appendix Table E-5). Milfoil was occasionally
an important food item for waterfowl (Appendix C), but perhaps only when
preferred foods were relatively scarce.
Horned pondweed (Zannichellia palustris) is another SAV species
that was uncommon in late summer during the 1970's (Appendix Table E-6),
and infrequently used by a number of waterfowl species. The distri-
bution and abundance of this SAV species were the most erratic of those
examined. It was essentially not recorded during four of the nine
surveys. This may have been caused by variation between years in the
timing of surveys, since horned pondweed apparently dies back during
summer (Stevenson and Confer 1978; Carter and Haramis 1980; L. J.
Hindman, personal communication).
Wildcelery, considered an excellent waterfowl food (Martin and
Uhler 1951), was found in the fresher reaches of only a few areas in the
Chesapeake Bay (Appendix Table E-7). Of the seven areas in which
wildcelery was found, only four yielded this valuable plant after 1971.
Based on frequency occurrence, wildcelery must now be considered an
uncommon plant in shoal waters of the Bay. Although historically
important to many waterfowl species (Appendix B), wildcelery is now
infrequently found in samples from these birds (Appendix D).
30
-------
We conclude that important waterfowl food plants, some of which
were very common during the late 1960's and 1971, became much less
abundant in both Maryland and Virginia waters particularly by 1973.
Frequency occurrence, as a measure of SAV abundance in Maryland,
indicated a downward trend in submerged aquatic plants as a group and
for most species. The lower Choptank River, Manokin and Annemessex
Rivers, Chester River, and Eastern Bay were consistently among the most
important areas for a number of SAV species.
CHESAPEAKE BAY WATERFOWL POPULATIONS IN PERSPECTIVE
Numbers of waterfowl observed during January surveys were used to
measure species abundance. Distribution of a species was first examined
by comparing the State population to the Atlantic Flyway population,
which was also compared to the United States total. Species
distribution and abundance among waterfowl survey areas were then
examined. We also examined the density of birds (per unit of shoal
water habitat) in Maryland waterfowl survey areas. In all cases we
tested a null hypothesis of no change in distribution/abundance of a
species.
We used survey results during a previous long-term period (1956-71
in Maryland, 1961-71 in Virginia) to test for trends in distribution and
abundance of waterfowl. These results provided a proper perspective
with which current (1972-80) waterfowl populations could be compared.
Maryland
The Maryland portion of Chesapeake Bay has been the most important
wintering area in the Atlantic Flyway for waterfowl in general. There
is no other area along the entire Atlantic coast that was as important
to so many birds of a variety of species. This was particularly true
31
-------
for whistling swans, Canada geese, and canvasbacks whose Maryland
populations comprised over 50 percent of Atlantic Flyway totals (Table
9). Maryland was also an important wintering area (>15 percent of
Flyway population) for ruddy ducks, buffleheads (Bucephala albeola),
goldeneyes, redheads, black ducks, and mallards during the long-term
period.
The whistling swan population was one of the few that increased
during the 1956-71 period. Numbers of swans increased significantly at
the State, Flyway, and U.S. levels. Current populations showed no
further change in number or percentage of the Flyway population that
wintered in Maryland. Routes of migration and wintering area site
selection of these birds are among the most traditional of all
waterfowl. The life-long bond between swan pairs and the maintenance of
the family unit throughout the young's first year foster development of
these traditions.
We examined survey area swan populations during the 1956-71 period
(Appendix Table F-l) and found a percentage distribution that was
essentially stable. The three most important areas for swans were the
lower Choptank River, the Chester River, and Eastern Bay. Swan densities
in these areas increased significantly, and mean densities were among
the highest in the Bay.
The Canada goose population in the Atlantic Flyway changed
dramatically during the 1956-71 period (Table 9). This population
averaged over 500,000 geese and increased at about 25,000 birds/year,
while Maryland's population averaged over 250,000 and increased at a
similar rate. The importance of Maryland (i.e., the percentage of the
Flyway population) increased at 2 percent/year. The goose population
32
-------
TABLE 9. MARYLAND WINTERING WATERFOWL POPULATIONS COMPARED TO THOSE IN THE ATLANTIC FLYWAY AND THE UNITED STATES
1956- 1971 1972 - 1980 1956 - 1980
Speci es
and parameter a
U. S.
Atlanti c
Maryland
U. S.
Atlantic
Maryland
U. S.
Atlantic
Maryland
Whistling swan
Number
Percent
Canada
Number
Percent
: mean
S.E.
C.V.
slope est. (n)
F value
P > F
: mean
S.E.
C.V.
slope est. (JO
F value
P > F
goose
: mean
S.E.
C.V.
slope est. (n)
F value
P > F
: mean
S.E.
C.V.
slope est. (JO
F value
p > F
96323
6103.2
25.3
3261.3
9.51
0.0081
1341418
68019.8
20.3
53052.3
87.30
0.0001
50390
3334.6
26.5
1853.4
10.89
0.0053
52.6
2.4
18. 1
-
515464
34730. 1
27.0
24869.5
37. 17
0.0001
38.0
1. 1
11.8
-
32866
2674.7
32.6
1319.2
7.36
I). 0168
64.7
2.7
16.7
-
264709
31169.4
47. 1
23117. 1
49.42
0.0001
48.7
3. 1
25.5
2. 1
23.79
0.0002
124394
5078.6
12.2
-
2263228
89992.6
11.9
71820.8
7.92
0.0260
68315
2673.6
11.7
-
55.4
2.4
13.2
-
791745
22743.7
8.6
-
35.2
0.8
6.9
-
33977
1448.2
12.8
-
50.6
3.3
19.4
-
511164
14255.0
8.4
-
64.7
1.4
6.6
-
106428
5055.7
23.8
2413.7
22.44
0.0001
1673270
104785.3
31.3
68244.1
261.00
0.0001
56843
2896.6
25.5
1536.6
35.94
0.0001
53.6
1.7
16.3
-
614925
35739.7
29. 1
22465.7
136.85
0.0001
37.0
0.8
11.0
-
33266
1767.8
26.6
-
59.6
2.5
20.8
-0.8
6.96
.0.0147
353433
31561. 1
44.6
19973. 1
150:86
0.0001
54.4
2.6
23.6
1.4
44.01
0.0001
Ruddy duck
Number
Percent
: mean
S.E.
C.V.
slope est. (n)
F value
p > F
: mean
S.E.
C.V.
slope est. (JO
F value
P > F
223187
9493.4
17.0
-
61268
5290.3
34.5
-
27.5
2. 1
30.3
-
18526
4736.9
102.3
.
26.9
4.9
73.6
-
164069
11320.8
20.7
-
65441
11229.8
51.5
-
39.8
5.9
44.8
5.1
10.87
0.0132
10062
2486.0
74. 1
-
17.6
4.3
74.2
201905
9218.5
22.8
-3056.3
7. 19
0.0133
62770
5147.4
22.8
-
31.9
2.7
42.7
-
15479
3225.6
104.2
-934.4
5. 11
0.0335
23.5
3.6
76.3
-1.1
6.40
0.0187
(conti nued)
-------
TABLE 9. (continued)
w
Speci es
Scoters
Number:
Percent'
and parameter a
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (JC)
F value
p > F
U. S.
203367
17006. 4
33. 4
-
Atlantic
'113832
13322. 1
46.8
-
55.0-
4. 1
29.8
-
Maryland
15937
7786.2
195.4
- • •
11.7
3.8
129.4
-
U. S. Atlantic
162941 65177
16745.6 12296. 1
30.8 56.6
-
38.2
3.2
25.2
-
Maryland
11447
1953.3
51.2
-
18.9
3.5
55.5
2.7
6.74
0.0356
U. S.
188814
12846.2
34.0
-
Atlantic
96316
10576.4
54.9
-
49.0
3.3
33.3
-1.0
5.37
0.0297
Maryland
14321
4990. 1
174.2
-
14.3
2.8
97.0
-
Bufflehead
Number5
Percent '
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (JO
F value
P > F
70457
5157.9
29.3
3330.8
20.21
0.0005
36094
3217. 1
35.7
1704.8
9.25
0.0088
51. 1
1.9
14.9
-
7161
1328.3
74.2
903.0
26.55
0.0001
18. 1
2.2
48.8
1.6
48. 12
0.0001
99491 56300
4542.4 3699.8
13.7 19.7
-
56.5
2.4
12.5
-
11550
1186.6
30.8
-
21.2
2.8
39.8
-2. 1
6.22
0.0414
80909
4605.4
28.5
2599. 1
51.22
0.0001
43368
3114.8
35.9
1639.0
34.49
0.0001
53.0
1.5
14.6
-
8741
1029.4
58.9
447.5
15.94
0.0006
19.2
1.7
45.0
0.5
5. 14
0.0331
Common goldeneye
Number^
Percent'
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (X)
F value
P > F
163204
5752.7
14. 1
-
74412
3696.7
19.9
-
45.5
1.4
12.0
-
20104
2362.2
47.0
-
26.2
2.4
36.9
-
136182 43897
5797.2 3407.1
12.8 23.3
-
32.6
2.5
22.9
-2.2
11.96
0.0106
9382
2359.0
75.4
- •
21.4
4.6
63.9
-
153476
4927.5
16. 1
-1922.0
11.31
0.0027
63427
3974.7
31.3
-2016.7
29.01
0.0001
40.8
1.8
21.5
-0.8
19.31
0.0002
16244
2000.8
61.6
-623.9
6. 14
0.0210
24.5
2.2
46.0
-
(continued)
-------
TABLE 9. (continued)
Speci es
Ameri can
Number:
Percent!
and parameter a
.wi geon
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (%)
F value
p > F
U. S.
1631096
65204.8
16.0
.
Atlantic
106334
5928. 1
22.3
-2609.5
5.30
0.0372
6.7
0.5
28.9
•
Maryland
H5921
2780.0
69.8
-1443.8
8.66
0..0107
13.9
1.9
55.3
-1.1
11.57
0.0043
U. S.
1301655
53427.0
12.3
-
-•
Atlantic
70648
5199.8
22. 1
-
5.4
0.4
20.3
-
Maryland
1777
394.4
66.6
-
2.7
0.6
67.6
-
U. S.
1512497
55543.7
18.4
-20596.0
9.76
0.0048
Atlantic
93487
5433.9
29. 1
-2626. 1
23.57
0.0001
6.3
0.4
28.3
-0. 1
5.59
0.0269
Maryland
10829
2242.9
103.6
-1171.9
33.30
0.0001
9.9
1.7
83.6
-0.9
47.41
0.0001
Black duck • •''...
Number:
Percent'
Mallard
Number!
Percent •
mean
S.E.
C.V.
slope est. (n)
F value
P > F
mean
S.E.
C.V.
slope est. (/O
F value
p > F
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (X)
F value
P > F
502796
17947.9
14.3
-11247.0
17.55
0.0009
7916455
365513.8
18.5
-
330573
11762.8
14.2
-6016.2
8.24
0.0123
66.0
1.4
8.3
-
231971
17025.0
29.4
-7424.7
5.16
0.0394
2.9
0.2
22.9
-
69395
7!>72.8
43.6
-3391.4
5.56
0.0335
20.5
1.5
29.9
•
42137
8998.4
85.4
•-
16.9
2.3
55.0
'
363702
17440.6
14.4
-13263. 1
6.51
0.0380
6754796
365612.6
16.2
-
253264
8047.7
9.5
-
70.1
1.6
6.9
-
211626
15832.0
22.4
11961.6
6.35
0.0398
3.2
0.3
26.0
0.3
20.76
0.0026
26663
2464.9
27.7
-
10.5
0.8
23.6
-
26410
2663.8
30.3
-
12.6
1.0
24.6
-
. 452722
18737.2 .
20.7
-11257.3
82.54
0.0001
7498258
287116.0
19. 1
108560.6
10.32
0.0039
302742
10976.9
18. 1
-6096.2
46.33
0.0001
67.5
1. 1
8.2
0.3
6.25
0.0200
224647
12247.2
27.3
-
3.0
0. 1
24.0
-
54011
6418.5
59.4
-3322.9
31.85
0.0001
16.9
,1.4
41.6
-0.7
28.6
0.0001
36475
5967.8
81.8
-
15.3
1.6
51.2
-
(conti nued)
-------
TABLE 9. (continued)
Species and parameter3
Pintail
Numbers
Percent!
-
mean
S.E.
C.V.
slope est. (n)
F value
P > F
mean
S.E.
C.V.
slope est. (X)
F value
P > F
U. S. Atlantic Maryland U. S. Atlantic
3729626 186798
204038.2 19327.9
21.9 41.4
-10981.3
11.80
0.0040
5.1
0.4
30.8
-0.2
15.75
0.0014
13254
4166.9
125.8
-2306. 1
10.73
0.0055
6. 1
1.3
88. 1
-0.7
7. 16
0.0181
5191300 822
211202.2 5863
12.2 21
-
1
0
25
11
.3
.4
-
.6
. 1
.7
-
Maryland U.
797
160
60
1
0
63
.8
.6
-
.0
.2
.4
-
S.
4255828
206193
24
84776
13.
0.00
.4
.2
.2
29
14
Atlantic Maryland
149147
16079.8
53.9
-8793.2
42.33
0.0001
3.8
0.4
55.2
-0.3
95.83
0.0001
8769
2904.8
165.6
-1294.6
17.37
0.0004
4.2
1.0
115.6
-0.4
19.09
0.0002
aPopulations (number and/or percent) Mere regressed against years. Slopes* which estimate rates of change per year,
are shown if significant (0.05 level). The Atlantic Flyway is shown as a percentage of the U.S. population* and the
w State is shown as a percentage of the Flyway population.
-------
stabilized during the current period but at a much higher level.
Maryland now winters more than 500,000 Canada geese> This increase,
which began during the 1950's, was caused by a wintering range expansion
of geese into agricultural lands particularly on Maryland's Eastern
Shore.
The distribution of geese in Maryland was stable, since only a few
minor (<1 percent) changes were detected during the long-term period
(Appendix Table F-2). Unlike other populations examined, densities of
birds increased in almost all areas. The Chester River, where goose
populations averaged 25 percent of the State total, was the most
important area, although the highest density (>14 birds/ha) was found in
the Sassafras River population.
We found minor changes in long-term and current Maryland
populations of ruddy ducks, scoters, buffleheads, goldeneyes, and scaup,
all of which are diving ducks and not primarily vegetarian in food
preferences. Species distributions within Maryland (Appendix F) were
generally stable, and densities were relatively low (except for scoters
along Calvert County's Bayshore (Appendix Table F-4). Important areas
varied, although the lower Choptank River and bayshore areas were
frequently prominent.
More than half the Atlantic Flyway canvasback population wintered
in Maryland during the 1956-71 period. During the current period, the
Flyway population increased in number but decreased as a proportion of
the U. S. total. Although the- current Maryland population showed no
trend, it averaged about 51,000 birds which was considerably less than
the long-term average of 87,000 canvasbacks. The percentage of the
current Flyway population that wintered in Maryland showed a definite
38
-------
downward trend of about -3 percent/year, although the canvasback is
still the most numerous duck in Maryland. Survey area populations of
canvasbacks (Appendix Table F-7) were stable in density and percent
distribution. The three most important areas were the lower Choptank
River, Calvert County Bayshore, and the Patuxent River.
The Maryland redhead population averaged about 38,000 birds prior
to 1972 with no detectable trend. However, there was a significant
decrease (-2 percent/year) in the proportion of the Flyway population
found in Maryland. Current redhead populations, although stable,
averaged only about 6,000 birds. This formerly abundant diving duck is
now found only in small numbers in Maryland. Area redhead populations
(Appendix Table.F-9) were largest in the lower Choptank River, although
density there trended downward significantly during the 1956-71 period.
The percent distribution of redheads among Maryland survey areas was
stable.
Average State populations (numbers) of wigeon, black ducks, and
pintails all decreased significantly during the long-term period (Table
9). Although current numbers of each species stabilized at lower
levels, average numbers of wigeon (1,800) and pintails (800) are now
minimal. Flyway populations of these three puddle ducks also trended
downward during the long-term which partially explains their current
scarcity. However, the Maryland wigeon population formerly comprised
about 14 percent of the Flyway population and it now represents less
than 3 percent. Similarly, Maryland became less important to Flyway
black ducks (20 - 10 percent) and pintails (6-1 percent). The Chester
River, Eastern Bay, and the lower Choptank River were among the three
most important areas for wigeon (Appendix Table F-10), black ducks
39
-------
(Appendix Table F-ll), and pintails (Appendix Table F-13), except for
Smith Island which was the most important pintail area. Within-State
distribution of wigeon changed more than any other species population
examined. The Chester River became less important to wintering wigeon
at a rate of -1.3 percent/year during the 1956-71 period-
The Maryland mallard population currently averaged about 26,000
birds which is less than the long-term average of 42,000 birds. On a
percentage basis, Maryland was only slightly less important to current
Flyway mallard populations (about 13 percent) than during the long-term
(17 percent). Mallards, which are closely related to black ducks, were
also most abundant in the Chester River (Appendix Table F-12).
Virginia
Virginia populations of whistling swans and Canada geese (Table
10), although stable during the long-term (1961-71), both increased
significantly in number and as a percentage of Atlantic Flyway total
during the current period (1972-80). Most swans in Virginia wintered in
areas such as ocean bays, which are beyond the scope of this study
(Appendix Table G-l). The most important area for Canada geese was the
Presquile National Wildlife Refuge (NWR) on the James River, where the
number of geese increased significantly during the 1961-71 period
(Appendix Table G-2). However, the distribution of geese in other
Virginia survey areas was essentially stable.
The ruddy duck population in Virginia averaged about 16,000 birds
or 30 percent of the Flyway population, with no apparent trends during
the 1961-71 period (Table 10). This population recently (1972-80)
averaged only 6,400 birds, an average that was stable but lower than the
previous long-term level. The distribution of ruddy ducks in Virginia
40
-------
TABLE 10. VIRGINIA WINTERING WATERFOWL POPULATIONS COMPARED TO THOSE IN THE ATLANTIC FLYWAY AND THE UNITED STATES
1961 -1971 1972 - 1980 1961 - 1980
Species and parameter3
Whistli
Number
Percent
Canada
Number
Percent
ng swan
' mean
S.E.
C.V.
slope est. (n)
F value
p > F
'• mean
S.E.
C.V.
slope est. (X)
F value
P > F
goose
: mean
S.E.
C.V.
slope est. (n)
F value
P > F
s mean
S.E.
C.V.
slope est. (X)
F value
P > F
U. S.
104572
7599.4
24. 1
-
1477593
63256.4
14.2
57348.5
41.54
0.0001
Atlantic
57326
2682. 1
15.5
-
56.2
2.6
15.2
-
581004
31690.0
18. 1
27440.7
26.97
0.0006
39.2
0.9
7.3
-
Vi rginia
3605
1234.8
113.6
-
6.4
2.0
105.7
-
46146
8404.2
60.4
-
7.8
1.0
42.9
-
U. S.
124394
5078.6
12.2
-
2263228
89992.6
11.9
71820.8
7.92
0.0260
Atlantic
68315
2673.6
11.7
-
55.4
2.4
13.2
- ' .
791745
22743.7
8.6
-
35.2
0.8
6.9
-
Vi rgi ni a
4357
881.5
60.7
800.9
15.43
0.0057
6.3
1.2
58.9
1. 1
13.67
0.0077
54385
7316.6
40.4
5470.6
6. 11
0.0428
6.7
0.8
34.3
0.6
6.59
0.0371
U. S.
113492
5169. 4
20.4
2111.4
7.42
0.0139
1831129
103599.8
25.3
74445.9
168.83
0.0001
Atlantic
62271
2238.2
16. 1
974.5
8.94
0.0079
55.9
1.7
14.0
-
675837
31100.4
20.6
21515.4
92.79
0.0001
37.4
0.7
8.9
-0.3
6. 15
0.0233
Vi rginia
3943
772.0
87.5
-
6.4
1.2
86.0
-
49854
5610. 1
50.3
-
7.3
0.6
39.6
-
Ruddy duck
Number
Percent
• mean
S.E.
C.V.
slope est. (n)
F value
p > F
•• mean
S.E.
C.V.
slope est. (%)
F value
P > F
229553
12295.8
17.8
-
57629
4983.2
28.7
-
25.2
1.9
25.0
•
15962
3204.5
66.6
-
29.6
5.5
61.9
-
164069
11320.8
20.7
-
65441
11229.8
51.5
•
39.8
5.9
44.8
5. 1
10.87
0.0132
6414
1669.3
78.1
9.3
2.3
74.2
-
200085
11131.3
24.9
-5459.5
13.09
0.0020
61144
5646.0
41.3
-
31.8
3.2
45.7
1.4
9. 10
0.0074
11665
2165.2
83.0
-856.2
6.78
0.0179
20.5
3.9
85.1
-1.6
7.29
0.0146
(conti nued)
-------
TABLE 10. (continued)
Species .
Scoters
Number:
Percent :
and parameter a
mean
S.E.
C.V.
slope est. (n)
F value
P > F
mean
S.E.
C.V.
U. S. Atlantic
221379 123289
22338.7 18134.9
33.5 48.8
-
54.1
5.3
32.4
Vi rgi ni a
3581
11213.3
112.4
-
3.3
1.2
118. 1
U. S. Atlantic
162941 65177
16745.6 12296.1
30.8 56.6
-
38.2
3.2
25.2
Virginia U. S.
10433 195082
5334.3 15558.6
153.4 35.7
-.
11.1
3.6
98.2
Atlantic
97139
12955.2
59.6
-
47.0
3.7
34.8
Vi rgi nia
6664
2535.6
170. 1
-
6.8
1.9
125.9
slope est. (JO
F value
p > F
Bufflehead
Number
•e-
N>
Percent!
mean
S.E.
C.V.
slope est. (n)
F value
P > F
mean
S.E.
C.V.
slope est. (JO
F value
P > F
Canvasback
Number^ mean
S.E.
C.V.
slope est. (n)
F value
P > F
Percent' mean
S.E.
C.V.
slope est. (JO
F value
P > F
81157
4130.3
16.9
261908
15941. 1
20.2
41986
3357.8
26.5
51.2
2.2
14. 1
145114
12629.5
28.9
54.7
2. 1
12.5
-1.4
6.81
0.0283
2678
649.4
80.4
5.8
1.2
68.4
9593
1936. 1
66.9
7.4
1.9
86.0
99491
4542.4
13.7
_
56300
3699.8
19.7
-
56.5
2.4
12.5
-
11638
2905.3
74.9
-
19.5
4.3
66.3
-
89408
3636.8
18.2
1798.7
13.47
0.0017
48427
2920.0
27.0
1292.8
9.40
0.0067
53.6
1.7
14.0
-
6710
1663.5
110.9
856.4
15.57
0.0009
11.9
2.5
94.6
1.4
18.38
0.0004
276858
20078.2
21.8
19442.7
25.02
0.0016
(conti nued)
125132
6687.4
16.0
5766.0
11.40
0.0118
45.9
1.4
9.4
-1.2
9.44
0.0180
9304
1776.5
57.3
7.2
1.3
55.6
268636
12363.5
20.6
136122
7736. 1
25.4
50.7
1.6
14.3
-1.0
32.84
0.0001
9463
1297.7
61.3
7.3
1.2
72.4
-------
TABLE 10. (continued)
1972 - 1980 1956 - 1980
Species .
Ameri can
Number:
Percent '
and parameter3
Hi geon
mean
S.E.
C.V.
slope est. (n)
F value
P > F
mean
S.E.
C.V.
U. S.
1638719
67149.6
13.6
Atlanti c
102944
7250.0
23.4
-
6.4
0.5
27. 1
Vi rgi ni a
3692
1030.9
92.6
-
3.8
1.1
97.2
U. S. Atlantic
1301655 70648
53427.0 5199.8
12.3 22.1
-
5.4
0.4
20.3
Vi rgini j
4968
1285.7
77.6
-
7.0
1.8
76.4
a U. S.
1487040
57671.9
17.3
-31908.6
20.77
0.0002
Atlantic
88411
5824.5
29.5
-3043.7
16.48
0.0007
6.0
0.3
25.6
Vi rgi ni a
4266
801.3
84.0
—
5.2
1.0
89.6
slope est. (%)
F value
p > F
U)
Black duck
Number:
Percent:
Mallard
Number:
Percent:
mean
S.E.
C.V.
slope est. (n)
F value
p > F
mean
S.E.
C.V.
slope est. (5J)
F value
P > F
mean
S.E.
C.V.
slope est. (n)
F Value
p > F
mean
S.E.
C.V.
slope est. (5O
F value
P > F
471543 316614
14446.7 9092.6
10.2 9.5
-5503.3
5.20
0.0485
67.3
1.3
6.6
-
7320124 206971
356716.6 12060.4
16.2 19.3
-
2.9
0.2
18.5
-
17405
2200.2
41.9
-1666.2
12. 10
0.0070
5.4
0.6
38. 1
-0.4
9.27
0.0139
8008
1130.7
46.8
-
4.0
0.5
44.5
-
363702
17440.6
14.4
-13263. 1
6.51
0.0380
6754796
365612.6
16.2
-
253264
8047.7
9.5
•
70. 1
1.6
6.9
-
211626
15832.0
22.4
11961.6
6.35
0.0398
3.2
0.3
26.0
0.3
20.76
0.0026
19988
4473.3
67.1
-
8. 1
1.8
68.2
1.4
7.21
0.0313
20325
4311.5
63.6
-
9. 1
1.5
48.6
-
423015
16417.7
17.4
-10292.6
39.65
0.0001
7065726
257536.7
16.3
-
288106
9406.4
14.6
-6097.1
49.99
0.0001
68.6
1. 1
6.9
-
209066
9480.5
20.3
-
3.0
0.2
22.7
-
18567
2297.8
55.3
—
6.6
0.9
62.0
-
13551
2422.5
80.0
1073.9
9.44
0.0066
6.3
0.9
65. 1
0.4
10.09
0.0052
Topulations (number and/or percent) Mere regressed against years. Slopes, which estimate rates of change per year,
are shown if significant (0.05 level). The Atlantic Flyway is shown as a percentage of the U.S. population* and the
State is shown as a percentage of the Flyway population.
-------
was the most restricted of all species populations examined. More than
half of the State population wintered in the lower Rappahannock River
area (Appendix Table G-3).
Populations of scoters and buffleheads, although stable in previous
and current periods, both increased during the latter period; canvasback
and wigeon populations, on the other hand, remained unchanged but at low
levels (Table 10). The lower Rappahannock River was the most important
canvasback area within a stable State distribution (Appendix Table G-6),
whereas the lower James River was most important to wigeon (Appendix
Table G-7).
The black duck population decreased significantly in Virginia and
the Atlantic Flyway prior to 1971, and then stabilized during the
current period. On a proportional basis, Virginia became more important
to Flyway black ducks at a rate of 1.4 percent/year from 1972 to 1980.
The Pamunkey River was the most important black duck area, although a
significant downward trend in numbers of black ducks was indicated for
that area (Appendix Table G-8).
The Virginia mallard population, which previously averaged 8,000
birds, recently increased to about 20,000 birds or 9 percent of the
Flyway total. As with the black duck, the Pamunkey River was the most
important area (Appendix Table G-9).
We conclude that Maryland waterfowl populations prior to the 1970's
were considerably larger and more diverse than those in Virginia. While
many duck populations in Maryland decreased during the 1970's, those in
Virginia increased or remained stable. Maryland populations of Canada
geese and whistling swans, in contrast to ducks, greatly increased
(geese) or remained stable (swans).
44
-------
EFFECTS OF SAV ON WATERFOWL
We have demonstrated that some Chesapeake Bay waterfowl species
feed principally on vegetation (including SAV), while others do not or
at least not to an appreciable extent. We have also shown that, while
waterfowl species distributions among survey areas were generally stable
prior to the 1970's, there have been significant changes in numbers of
birds at the State level and/or in the importance of Maryland and Virginia
to Atlantic Flyway populations. We are now able to examine the
relationship between the distribution and abundance of waterfowl and the
distribution and abundance of SAV in Maryland during the 1972-80 period.
Although some SAV species are more important than others as
waterfowl food resources, all were combined in the analyses presented
here. As in previous analyses of waterfowl distributions, birds
surveyed in upland, inland reservoir, and ocean bay habitats were
excluded. Of the 13 waterfowl species whose Maryland populations were
previously examined, 4 were excluded from consideration here due to the
scarcity of their numbers during the 1972-80 period. These are the
ruddy duck, redhead, wigeon, and pintail. Maryland populations of the
latter three species, which feed extensively on SAV, are currently at
their lowest recorded levels.
The remaining nine populations were each run through the simple
linear model described earlier (see STATISTICAL ANALYSES), which
examined the hypothesis that annual variation in survey area populations
is related to annual variation in the distribution and abundance of SAV
and the general abundance of the species. Appropriateness of the full
model was not the same for the nine species populations. We therefore
examined a number of alternative or reduced models, based on preliminary
45
-------
results. For example, if an analysis indicated that SAV had no
measurable effect on numbers of sea ducks, a more appropriate or
efficient model would not include an SAV term- For each species, we
removed non-significant (p > 0.05) parameters and reran the analysis.
The analyses presented here are therefore the simplest, as they include
only significant effects.
Swans and Geese
Whistling swans and Canada geese in Maryland provide an interesting
comparison. Both are large, long-lived birds with stable or increasing
populations. Maryland is the most important wintering area in the
Atlantic Flyway for both populations. Although both feed in
agricultural fields, swans have done so to an appreciable extent only
during the 1970's.
Our analysis of survey area swan populations (Table 11) indicates
there is a measurable effect of SAV abundance on numbers of swans in a
few areas, all of which were important wintering areas during the
previous long-term period (Appendix Table F-l). For example, the effect
of SAV on swan numbers in Eastern Bay was significant (1.2 birds/ha of
SAV). We also found a significant intercept (1,753 birds), which
measures the level of a survey area's population that is independent of
variation in either SAV or the general abundance of swans. The Wye
River swan population was exceptional due to the rather large, negative
relationship with SAV abundance, which was caused by large numbers of
swans when SAV was uncommon. This area has recently become an important
loafing area for an increasing number of field-feeding swans.
In contrast to swans, there is no relationship (p > 0.05) between
distribution and abundance of Canada geese and SAV in Maryland (Table
46
-------
TABLE 11. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF WHISTLING SWANS ARE RELATED TO THE DISTRIBUTION
AND ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c e a
Intercept
SAV X Survey area
Eastern Bay
Chester Ri ver
Lower Choptank River
Wye River
Flyway * Survey area
Wye River
df
1
22
( 1)
( 1)
( 1)
( 1)
24
( 1)
F value
4.20
1.90
7.45
7.24
11.83
9.67
2. 11
12.74
P>F
0.0419
0.0126
0.0070
0.0078
0.0007
0.0022
0.0034
0.0005
Parameter
estimate
1753.
1.222
1. 127
0.7685
-5.997
0.0780
Parameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero.
-------
12). Numbers of geese in survey areas are entirely explained by
variation in the Atlantic Flyway population. In fact, populations of
geese on Maryland's Eastern shore may be responsible for much of the
variation in the Atlantic Flyway total. Open water areas are now used
mostly for loafing and protection from predators, as geese have become
essentially dependent on surrounding agricultural lands for food.
Black Ducks and Mallards
These species have been and continue to be the most common and
widely distributed puddle ducks in Maryland, although current
populations of both, are considerably less than long-term levels. We
found that black duck numbers in the Chester River were significantly
related to the abundance of SAV (about 3 birds/ha of SAV, Table 13).
This area was also the most important wintering area for black ducks
during the 1956-71 period (Appendix Table F-ll). Black ducks in the
Honga River and Bloodsworth-South Marsh Islands areas also varied with
SAV, but at lesser rates (about 0-6 birds/ha of SAV). Populations in a
number of other areas varied with the general abundance of the species*
Mallard numbers in the Chester River were also related to the
abundance of SAV (about 2.7 birds/ha of SAV, Table 14). However, bird
numbers in other areas were not similarly affected. Although mallards
are found in all survey areas, most of the variation in population size
was related to the general abundance of mallards in a few areas, except
in the Chester River.
Diving Ducks
Although plant material comprised only 25-30 percent of the food
habits of buffleheads, we found that numbers of these birds in the
Manokin, Annetnessex Rivers and Eastern Bay areas were related to the
48
-------
TABLE 12. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF CANADA GEESE ARE RELATED TO THE DISTRIBUTION
AND ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c e a
Flyway x Survey area
Chester River
Bayshore, Kent County
Lower Choptank River
Sassafras River
Northeast - Elk - Bohemia Rivers
Wye River
Upper Choptank River
Eastern Bay
Miles River
Little Choptank River
Patuxent River
Nanticoke - Wicomico Rivers
df
24
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
F value
165. 10
2,714.41
320.77
251.22
221.71
162.82
97.02
64.32
57. 15
34.57
14.36
12. 11
5.57
p>F
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0002
0.0006
0.0194
Parameter
estimate
0. 1899
0.0653
0.0578
0.0543
0.0465
0.0359
0.0292
0.0275
0.0214
0.0138
0.0127
0.0086
VO
Parameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero. Since the effect of SAV
Mas not significant (0.05 level), it was not included in the above analysis.
-------
TABLE 13. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF BLACK DUCKS ARE RELATED TO THE DISTRIBUTION
AND ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYUAY
POPULATION) OF THE SPECIES
S o u r c e a
SAV * Survey area
Chester River
Honga River
Bloodsworth - South Marsh Islands
Lower Choptank River
Patapsco River - Aberdeen P.G.
Flyway * Survey area
Patapsco River - Abderdeen P.G.
Manokin, Annemessex Rivers
Nanticoke - Micomico Rivers
Patuxent River
Upper Choptank River
Chester River
df
22
( 1)
( 1)
( 1)
( 1)
( 1)
24
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
F value
7.65
126.56
9.24
12.74
4.71
5.43
4.55
9.67
15. 13
29.81
7.95
13.25
17. 14
p>F
0.0001
0.0001
0.0028
0.0005
0.0312
0.0213
0.0001
0.0022
0.0001
0.0001
0.0054
0.0004
0.0001
Parameter
estimate
2.988
0.6780
0.6218
0.2958
-1.391
0.0091
0.0074
0.0051
0.0046
0.0042
-0.0123
Ln
O
Parameter estimates and test statistics are shown
only if significantly different (p<.05) from zero.
for individual survey areas
-------
TABLE 14. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF MALLARDS ARE RELATED TO THE DISTRIBUTION AND
ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
Source3 df
SAV * Survey area 22
Chester River ( 1 )
Flyway * Survey area 24
Wye River (1)
Bayshore, Kent County ( 1)
Patuxent River ( 1)
Upper Choptank River ( 1)
Nanticoke - Wicomico Rivers ( 1)
Northeast - Elk - Bohemia Rivers ( 1)
F value
2. 18
41.47
2.95
7.84
30.80
3.92
6.35
6.55
3.92
p>F
0.0029
0.0001
0.0001
0.0056
0.0001
0.0496
0.0125
0.0115
0.0494
Parameter
estimate
2.747
0.0138
0.0115
0.0065
0.0056
0.0051
0.0044
aParameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero.
l/l
-------
abundance of SAV (Table 15). The relationship (0.3 birds/ha of SAV) was
less pronounced than in the puddle ducks examined, but more important
than general species abundance in these areas. Population variation in
other important bufflehead areas, such as the lower Choptank and Little
Choptank Rivers, simply reflected changes in general abundance.
We demonstrated earlier that the food habits of canvasbacks in
Chesapeake Bay changed during the 1970's more than any other species
examined. Canvasbacks now feed extensively on small (<25 mm) Baltic
macoma clams and other invertebrates and infrequently on SAV. When we
analyzed current distribution and abundance of canvasbacks, we found no
relationship with distribution and abundance of SAV (Table 16). We did
find a significant intercept (1,910 birds), which is common to all
areas, that estimates a population level independent of SAV or species
abundance. If the area-specific effect of general abundance is not
significant, then that area's population is estimated by the intercept.
However if it is significant, the product of the area's parameter
estimate and the Flyway population in a given year is added to the
intercept. Estimated canvasback populations in areas listed under
"Flyway x Survey area" in Table 16 are therefore greater or less than
1,910 birds.
Maryland populations of scaup and common goldeneyes also were not
related to the distribution and abundance of SAV. Interpretation of our
analysis of scaup populations (Table 17) is complicated somewhat by the
large, negative intercept (-2,551 birds). This was primarily caused by
extrapolating beyond the range of the data. Although area populations
should be small during years when scaup are relatively scarce, a
straight line fit yielded a negative intercept. However, a model that
52
-------
TABLE 15. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF BUFFLEHEADS ARE RELATED TO THE DISTRIBUTION
AND ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o • u r c e a
SAV x Survey area
Manokin, Annemessex Rivers
Eastern Bay
Flyway x Survey area
Lower Choptank River
Little Choptank River
Patuxent River
Bayshore, Calvert County
Honga River
df
22
( 1)
( 1)
24
( 1)
( 1)
( 1)
( 1)
( 1)
F value
2. 14
30.25
4.93
2.38
5.52
14.75
9.24
12.89
4.62
P>F
0.0037
0.0001
0.0279
0.0007
0.0199
0.0002
0.0028
0.0004
0.0333
Parameter
estimate
0.3614
0.3398
0.0138
0.0136
0.0118
0.0098
0.0072
aParameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero.
-------
TABLE 16. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF CANVASBACKS ARE RELATED TO THE DISTRIBUTION
AMD ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c a a
Intercept
Flyway * Survey area
Patuxent River
LOHQT Choptank River
Magothy - Severn Rivers
South River - Herring Bay
Susquehanna Flats
Northeast - Elk - Bohemia Rivers
Sassafras River
Bayshore, Kent Island
df
1
24
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
F value
7.02
10. 17
22.85
14.59
7.39
4.71
4.53
4.49
4.49
4. 16
p>F
0.0087
0.0001
0.0001
0.0002
0.0071
0.0312
0.0347
0.0356
0.0356
0.0427
Parameter
estimate
1910.
0.0335
0.0268
0.0191
0.0152
-0.0149
-0.0148
-0.0148
-0.0143
Ul
Parameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero. Since the effect of SAV
was not significant (0.05 level), it was not included in the above analysis.
-------
TABLE 17. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY A-REA
POPULATIONS OF SCAUP ARE RELATED TO THE DISTRIBUTION AND
ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c e a
Intercept
Flyway * Survey area
Fishing Bay
Magothy - Severn Rivers
Chester River
South River - Herring Bay
Bayshore, Kent Island
Patuxent River
Patapsco River - Aberdeen P.G.
Bayshore, Calvert County
df
1
24
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
( 1)
F value
4.71
2.87
49.84
13.47
8.07
7.08
4.75
4.75
4.54
4.08
p>F
0.0314
0.0001
0.0001
0.0003
0.0049
0.0084
0.0302
0.0302
0.0343
0.0449
Parameter
est i mate
-2551.
6.0280
0.0146
0.0113
0.0106
0.0087
0.0087
0.0085
0.0080
rt
Parameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero. Since the effect of SAV
was not significant (0.05 level), it Mas not included in the above analysis.
-------
includes an intercept (if significant) better explains the variation in
area populations than does one without an intercept. Scaup populations
in areas not listed in Table 17 are essentially very low, or at least
not affected by general species abundance.
Although our analysis of common goldeneye populations led to the
same conclusion (i.e., no SAV relationship), interpretation of results
shown in Table 18 is simpler. Goldeneyes are uncommon in most survey
areas, but relatively common and responsive to general abundance in
areas such as Eastern Bay and the lower Choptank River.
We examined scoter or sea duck populations in Maryland with the
same set of models, since these birds contrast greatly with other
waterfowl in food and habitat preferences. As anticipated, we found no
relationship between distribution and abundance of SAV and scoters.
Small populations of these birds are widely scattered around the Bay
(significant intercept), and concentrated in only a few areas such as
the lower Choptank and Chester Rivers (Table 19).
We conclude that populations of wigeon, pintails, and redheads, all
predominantly vegetarian in food preferences, declined to very low
numbers in Maryland during the 1970's as a direct result of the SAV
decline. Although swan populations showed a response to the level of
SAV in a few important areas, black ducks and mallards were generally
more affected. Diving ducks as a group showed little relationship if
any to the distribution and abundance of SAV.
The distribution of waterfowl populations among survey areas
indicates that a few areas are consistently among the most important to
the various species examined. The Chester River, Eastern Bay, and lower
Choptank River, which are among the four most abundantly vegetated
56
-------
TABLE 18. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF COMMON GOLDENEYES ARE RELATED TO THE DISTRIBUTION
AND ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c e a
Flyway X Survey area
Eastern Bay
Lower Choptank River
Patuxent River
Chester River
Bayshore, Kent Island
df
24
( 1)
( 1)
( 1)
( 1)
( 1)
F value
4
60
21
18
5
4
.98
.06
.34
.92
.06
.20
0
0
0
0
0
0
P>F
.0001
.0001
.0001
.0001
.0255
.0416
Parameter
est i mate
0.
0.
0.
0.
0.
0410
0245
0230
0119
0109
aParameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero. Since the effect of SAV
Mas not significant (0.05 level), it Mas not included in the above analysis.
-------
TABLE 19. RESULTS OF TESTING THE HYPOTHESIS THAT MARYLAND SURVEY AREA
POPULATIONS OF SCOTERS ARE RELATED TO THE DISTRIBUTION AND
ABUNDANCE OF SAV, AND THE GENERAL ABUNDANCE (ATLANTIC FLYWAY
POPULATION) OF THE SPECIES
S o u r c ea
Intercept
Flyway X Survey area
Lower Choptank River
Chester River
Eastern Bay
Patuxent River
df
1
( 1)
( 1)
( 1)
( 1)
F value
4.66
5.53
61.62
23.81
16.89
12. 11
0
0
0
0
0
0
P>F
.0324
.0001
.0001
.0001
.0001
.0006
Parameter
estimate
234.5
0.0286
0.0177
0.0149
0.0126
Parameter estimates and test statistics are shown for individual survey areas
only if significantly different (p<.05) from zero. Since the effect of SAV
Mas not significant (0.05 level), it Mas not included in the above analysis.
Ui
oo
-------
areas, are equally important as waterfowl wintering areas. We interpret
this as additional evidence of a relationship between the distribution
of waterfowl and SAV.
IMPACT'S OF WATERFOWL ON SAV
Prior to this point we have attempted to clarify relationships
between SAV as food resources and waterfowl as consumers. Our objective
here is to evaluate the possibility that Chesapeake Bay waterfowl
populations are in any way responsible for recent declines in
distribution and abundance of submerged aquatic vegetation.
We are reminded, first of all, that waterfowl wintered in
Chesapeake Bay long before recorded history. Populations of these
birds, which have consumed SAV in the Bay for centuries without adverse
impact, can be(examined only during the last 25-30 years. Maryland
waterfowl populations with one exception were larger during the early
1950's when SAV was certainly more abundant as well. The Canada goose
population was the exception, as it began to increase during the
mid-1950's when the mechanization of agriculture increased the
availability of unharvested cereal grains.
We showed that distributions of waterfowl species populations in
Maryland were generally stable prior to the 1970's. We showed further
that three areas, the Chester River, Eastern Bay, and the lower Choptank
River, consistently wintered the highest proportions of Maryland's
waterfowl populations during both long-term and current periods. We
conclude that 1) these populations most likely reflect greater abundance
of SAV in these areas compared to other areas, and 2) since these areas
continue to winter most of the waterfowl and produce most of the SAV,
these birds cannot be responsible for recent declines in their food
resources.
59
-------
REFERENCES
Barr, A. J., J. H. Goodnight, J. P. Sell, and J. T. Helwig. 1976. A
user's guide to SAS 76. SAS Inst. Inc., Raleigh, N.C. 329 pp.
Bayley, S., V. D. Stotts, P. F. Springer, and J. Steenis. 1978.
Changes in submerged aquatic macrophyte populations at the head of
the Chesapeake Bay, 1958-1975. Estuaries 1(3):171-182.
Bellrose, F. C. 1976. Ducks, geese and swans of North America.
Stackpole Books, Harrisburg, Pa. 543 pp.
Benning, D. S., S. L. Rhoades, L. D. Schroeder, and M. M. Smith, eds.
1978. Waterfowl status report, 1974. U.S. Fish Wildl. Serv.
Spec. Sci. Rep.-Wildl. 211. 98 pp.
Bent, A. C. 1923. Life histories of North American wild fowl. Order:
Anseres (Part I). U.S. Natl. Mus. Bull. 126. Washington, B.C.
244 pp.
Carter, V., and G. M. Haranis. 1980. Distribution and abundance of
submersed aquatic vegetation in the tidal Potomac River -
implications for waterfowl. Atl. Naturalist 33:14-19.
Cottam, C. 1939.. Food habits of North American diving ducks. U.S.
Dept. Agric. Tech. Bull. 643. 140 pp.
Elser, H. J. 1967. Status of aquatic weed problems in tidewater
Maryland, spring 1967. Manatee project, Md. Dept. Ches. Bay
Affairs, Annapolis. (11 pp. mimeo)
Johnson, D. H. 1980. The comparison of usage and availability
measurements for evaluating resource preference. Ecology
61(1):65-71.
Kerwin, J. A., R. E. Munro, and W. W. A. Peterson. 1976. Distribution
and abundance of aquatic vegetation in the upper Chesapeake Bay,
1971-1974, p. 393-400 ±n J. Davis, coord. The effects of tropical
storm Agnes on the Chesapeake Bay estuarine system. Chesapeake
Res. Cons. Publ. No. 54, The Johns Hopkins Univ. Press,
Baltimore, Md. 639 pp.
Korschgen, L. J. 1969. Procedures for food-habits analyses, p. 233-250
Jji R. H. Giles, Jr., ed. Wildlife management techniques. Wildlife
Society, Washington, D.C. 623 pp.
Lincoln, F. C. 1950. The American brant - living bird or museum piece.
Audubon Mag. 52:282-287.
Martin, A. C. and F. M. Uhler. 1951. Food of game ducks in the United
States and Canada. Res. Rep. 30, U.S. Fish Wildl. Serv. 308 pp.
Martin, A. C., R. H. Gensch, and C. P. Brown. 1946- Alternative
methods in upland gamebird food analysis. J. Wildl. Manage.
:8-12.
60
-------
Munro, R. E. (in prep.). Field feeding by whistling swans in Maryland.
Proc Second Int. Swan Symp.
Orth, R. J., K. A- Moore, and H. H. Gordon. .1979. Distribution and
abundance of submerged aquatic vegetation in the lower Chesapeake
Bay, Virginia. EPA Report No. 600/8-79-029/SAV1. 199 pp.
Penkala, J. M. 1975. Winter food habits and body weight of Atlantic
Brant. Trans. N.E. Fish Wildl. Conf. 32:151-169.
Perry, M. C., and F. M. Uhler. 1976. Availability and utilization of
Canvasback food organisms in Chesapeake Bay. Presented at Spring
Meeting of the Atlantic Estuarine Research Society, Rehoboth Beach,
Del. (25 pp. mimeo)
Pfitzenmeyer, H. T., and K. G. Drobek. 1964. The occurrence of the
brackish water clam, Rangia cuneata, in the Potomac River,
Maryland. Ches. Sci. 5(4):209-215.
Rawls, C. K. (in prep.). Food habits of waterfowl in the upper
Chesapeake Bay, Maryland. Univ. of Maryland Center for
Environmental and Estuarine Studies. 140 pp.
Springer, P. F., and R. E. Stewart. 1959- Condition of waterfowl
feeding grounds on the Susquehanna Flats during the fall of 1959
with notes on the invasion of a serious pest plant. U.S. Fish
Wildl. Serv., Patuxent Wildl. Res. Ctr., Laurel, Md. (7 pp.
mimeo)
Stevenson, J. C., and N. M. Confer. 1978. Summary of available
information on Chesapeake Bay submerged vegetation. Final report
to FWS/OBS-78/66. 335 pp.
Stewart, R. E. 1962. Waterfowl populations in the upper Chesapeake Bay.
U.S. Fish Wildl. Serv. Spec. Sci. Rep.-Wildl. 65. 208 pp.
Swanson, G. A., and J. C. Bartonek. 1970. Bias associated with food
analysis in gizzards of blue-winged teal. J. Wildl. Manage.
34(4):739-746.
Swanson, G. A., G. L. Krapu, J. C. Bartonek, J. R. Serie, and D. H.
Johnson. 1974. Advantages in mathematically weighting waterfowl
food habits data. J. Wildl. Manage- 38(2):302-307.
Yocom, C. F. 1951. Waterfowl and their food plants in Washington.
Univ. of Washington Press, Seattle, Wash. 272 pp.
61
-------
APPENDIX TABLE A-1. SCIENTIFIC AND COMMON NAMES OF ANIMAL AND PLANT FOOD ITEMS OF CHESAPEAKE BAY WATERFOWL
Animal food items Plant food items
Acrididae (Locustidae)
Aedes sollicitans
Aedes spp.
Aeschnidae
Amara spp.
Amnicola limosa
Amntcola spp.
Amnicoliidae (Bulimidae)
Amphipoda
Amygdulum papyria (Volsella)
Anachi s avara
Anculosa spp.
Ancylidae
Anguilla rostrata
Anguilla spp.
Angui11i dae
Ani soptera
Annelida
Anodonta grand;s
Anodonta imbecilis
Anthribidae
Anthuri dae
Aoridae
Apeltes quadracus
Aphi dae
Aphodius spp.
Arachni da
Araneae
Arcuatula demissa (Volsella)
Arthropoda
Ascidiacea
Aselli dae
Asellys spp.
Astacidae
Atherinidae
Atheta spp.
Bairdiella chrysura
Balanidae
Balanus eburneus
Balanus improvisus
Balanus spp.
Batrachoi di dae
Belastoma spp.
Belastomi dae
undetermind animal
undetermined fish
short-horned grasshopper
salt marsh mosquito
mosqui to
darner
amnicola
swamp snail
scud, sideswimmer
paper mussel
greedy dove shell
river snai1
1impet
American eel
eel
eel
dragonfly
leech, polychaete
fungus weevil
aquatic sowbug
aphid, plantlice
dung beetle
spi der
Atlanti c
ribbed mussel
aquatic sowbug
crayfi sh
silver perch
rock barnacle
ivory barnacle
bay barnacle
barnacle
toadfish
giant water bug
Abutilon Theophrasti
Acalypha rhomboidea
Acalypha spp.
Acnida cannabinus (amaranthus)
Agrostemma Githago
Aizoaceae
Albizia Julibrissin
Alisma Plantago~aquatica
Ali smataceae
Allium vineale
Alnus serrulata
Amaranthaceae
Amaranthus hybridus
Amaranthus spp.
Ambrosia artemisiifolia
Ambrosia spp.
Ambrosia trifida
Ampelopsis arborea
Ampelopsis spp.
Anacardi aceae
Andropogon spp.
Andropogon Gerardi
Aneilema Kei sak
Aqui foli aceae
Araceae
Arthraxon hispidus
Aster puniceus
Aster spp.
Aster tenuifolius
Atriplex patula
Avena fatua
Avena sativa
Baccharis halimifolia
Berchemia scandens
Betula nigra
Bidens laevis
Bidens spp.
Boehemeria cylindrica
Brasenia Schreberi
Bromus secalinus
Butomaceae
Butomus umbellatus
Capri foliaceae
Carex crinita
(continued)
woody bark fragments
undetermined vegetation
velvet-leaf (pie-marker)
three-seeded mercury
three-seeded mercury
tidemarsh waterhemp
corn-cockle
carpet-weed
acacia (silk-tree)
broadleaf waterplantain
watei—plantai n
field garlic (scallion)
smooth alder
amaranth
prince's feather
amaranth
ragweed
ragweed
ragweed
peppei—vi ne
cashew
beard grass
beard grass
marsh day-flower
holly
arum
grass
wi Id aster
aster
spearscale
wiId oat
oats
groundsel tree
supple-jack
river birch (red birch)
beggai—ti ck
beggar-ti ck
false nettle
watershield
cheat (chess)
flowering rush
flowering rush
honeysuckle
sedge
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food
items
Berosus spp.
Bethyli dae
Bidessus spp.
Bittium alternatum (B. nigrum)
Bittium spp.
Bittium varium
Bolesoma nigrum (Ethesoma)
Brachiodontes recurvus (Mytilus)
Brevoortia tyrannus
Bryozoa (Ectoprocta)
Callinectys sapidus
Calyptraei dae
Cambarus diogenes
CampGloma decisum
Campeloma integrum
Campeloma spp.
Cancer borealis
Cancri dae
Canthydrus puncticollis
Carabi dae
Caralsi dae
Cardi i dae
Cassidinidea lunifrons
Centrarchi dae
Ceratopogoni dae
Ceri thi i dae
Cerithiopsidae
Cerithopsis spp.
Chalepus dorsalis
Cheilostomata
Chilognatha
Chiridotea caeca
Chironomidae
Chordata
Chrysomeli dae
Cicadelli dae
Cladocera
Clupei dae
Coelambus spp.
Coelenterata (Cnidaria)
Coleophoridae
Coleoptera
Congeria leucophaeta
Copelatus glyphicus
Copcpoda
Corbicula fluminea
bethylid
alternate bittium
variable bittium
hooked mussel
Atlantic menhaden
blue crab
cup and saucer limpet
northern crab
ground beetle
cockle
biting midge, punky
horn shell
cerith
i sopod
mi dge
leaf beetle
leafhopper
water flea
herring
hydroid, jellyfish
casebearer
beetle
Conrad's false mussel
diving beetle
copepod
(conti
Carex festucacea
Carex hormathodes
Carex hyalinolepis
Carex intumescens
Carex lupjlina
Carex lurida
Carex scoparia
Carex spp.
Carex stricta
Carpinus caroliniana
Carya spp.
Caryophyllaceae
Cassia fasciculata
Cassia spp.
Celt is occidentalis
Celtis spp.
Centella erecta (asiactica)
Cephalanthus occidentalis
Ceratophyllaceae
Ceratophyllum demersum
Chara spp.
Characeae
Charophyceae
Chenopodi aceae
Chenopodium album
Chenopodi urn spp.
Chlorophyceae
Cicuta maculata
Cicuta spp.
Cladium jamaicense
Cladium mariscoides
Cladium spp.
Cladophora spp.
Cladophoraceae
Commelina communis
Commelina virginica
Commelinaceae
Compositae
Convolvulaceae
Cornaceae
Cornus florida
Cornus spp.
Cornus stolonifera
Cornus Amomum
Corylaceae
Crataegus spp.
nued)
sedge
sedge
lake sedge
sedge
sedge
sedge
sedge
sedge
hornbeam (blue beech)
hickory
pi nks
partridge-pea (locust-weed)
senna
hackberry
elm
parsley
buttonbush
hornwort
hornwort
muskgrass
muskgrass
muskgrass, stonewort
goosefoot
lamb's quarters
goosefoot
green algae
uiatei—hemlock
watei—hemlock
sawgrass
twig-rush
green algae
day-flower
day-flower
spi derwort
composi te
morning glory, convolvulus
dogwood
flowering dogwood
dogwood
red osier
dogwood
hazel
hawthorn
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food items
Corbicula manilensis
Corbiculiidae (Cyrenidae)
Cori xi dae
Corophi i dae
Corophi urn spp.
Crangon spp.
Crangoni dae
Crangonyx spp.
Crepidula convexa
Crepidula fornicata
Crepidula spp.
Cristatella mucedo
Crustacea
Culi ci dae
Culicoides spp.
Cumacea
Curculi oni dae
Cyathura carinata (-polita)
Cyathura polita
Cyathura spp.
Cydepistonus castaneus
Cypri dae
Cypri ni dae
Cyprinodon yariegatus
Cypri nodonti dae
Cypris spp.
Cyrenoida floridana (Cyrenella)
Cyrenoididae (Cyrenellidae)
Daphnia spp.
Daphnidae
Dacapoda
Dermaptera
Diplopoda
Di ptera
Dolomedes spp.
Donacia spp.
Doru lineare
Drei ssenidae
Dyti sci dae
Dyti scus spp.
Edotea spp.
Edotea triloba
Elateri dae
Electra crustulenta
Elliptic complanata (Unio)
Elliptic spp.
Asiatic fresh-water clam Crotolaria spectabilis
marsh clam
Mater boatman
scud, sideswimmer
amphi pod
sand shrimp
pistol shrimp
amphi pod
convex slipper shell
common slipper shell
slipper shell
crustacean
mosqui to
punky
snout beetle
i sopod
isopod
i sopod
seed shrimp
mi nnow
sheepshead minnow
top mi nnow
seed shrimp
clam, mussel
water flea
water flea
crayfish, shrimp
earwi g
mi 11i ped
fly
fishing spider
long-horned leaf beetle
false mussel
predaceous diving beetle
predaceous diving beetle
i sopod
click beetle
lacy crust
(continued)
Cuscuta spp.
Cynodon Dactylon
Cyperaceae
Cyperus albomarginatus
Cyperus erythrorhizos
Cyperus escylentus
Cyperus filicinus
Cyperus flavescens
Cyperus odorattes
Cyperus rotundus
Cyperus spp.
Cyperus strigosus
Cyperus Iria
Datura stramonium
Decodon verticillatus
Digitaria filiformis
Digitaria sanguinalis
Digitaria spp.
Digitaria Ischaemum
Diodia teres
Dioscoreaceae
Discorea quaternata
Discorea villosa
Distichlis spicata
Echinochloa colonum
Echinochloa crusgalli
Echinochloa spp.
Echinochloa Ualteri
Eclipta alba
Eleocharis obtusa
Eleocharjs olivacea
Eleocharis palustris
Eleocharis parvula
Eleocharis quadrangulata
Eleocharis spp.
Eleocharis Engelmanni
Eleusine indica
Elodea canadensis
Elodea spp.
Enteromorpha clathrata
Enteromorpha intestinalis
Enteromorpha spp.
Eulalia viminea
Euphorbia spp.
Euphorbiacsae
rattlebox
dodder
bermuda grass (wire grass)
sedge
galingale
redroot cyperus
galingale
gali ngale
gali ngale
galingale
galingale
galingale
galingale
gali ngale
jimson-weed
watei—wi How •
crab grass
crab grass '
crab grass
crab grass
buttonweed
yam
wiId yam
wiId yam
salt grass
jungle rice
barnyard grass
composite
blunt spikerush
spi kerush
common spikerush
dwarf spikerush
squarestem spikerush
spi kerush
yard grass
common elodea
filamentous green alga
green alga
filamentous green algae
spurge
spurge
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food items
01
Enochrus spp.
Ephemeridae
Ephemeroptera
Epitoni i dae
Epitonium rupicola
Erichsonella attenuata
Erichsonella spp.
Eros spp.
Euparius marmoreus
Eurypanopeus depressus
Forf i cyli dae
Formici dae
Fulgori dae
Fundulus heteroclites
Fundulus spp.
Galerucella spp.
Gammaridae
Gammarus fasciatus
Gammarus mucronatus
Gammarus palustris
Gammarus spp.
Gammarus tigrinus
Gasterostei dae
Gasterosteus aculeatus
Gastropoda
Golastocoridae
Gemma gemma
Gerri dae
Gillja altilis
Gobi i dae
Gobiosoma bosci
Gobiosoma spp.
Goniobasis spp.
Goniobasis virginica
Graphoderes spp.
Graphops pulsescens
Grapsi dae
Grylli dae
Gryllotalpa
Gyralus deflectus
Gyralus parvus (Planorbis)
Gyralus spp. (Planorbis spp.)
Gyri ni dae
Haliplidae
Heliosoma antrosa (Planorbis)
Heliosbma spp. (Planorbis spp
burrowing mayfly
mayfly
wentletrap
lined wentletrap
i sopod
i sopod
mud crab
common earwig
ant
fulgorid planthopper
leaf beetle
scud
scud
scud
scud
scud
scud
snail, limpet
toad bug
gem clam
water strider
snail
goby
goby
naked goby
snai 1
snai 1
cricket
northern mole cricket
fresh Mater snail
whirligig beetle
crawling water beetle
) orb snail
(conti
Fagaceae
Festuca elatior
Festuca spp.
Fimbristylis castanea
Fimbristylis spp.
Fraxinus americana
Fui rena spp.
Galium spp.
Geraniaceae
Geranium spp.
Gerardia maritima
Glyceria striata • .
Glycine Max
Gracilari a spp.
Grami neae
Haloragaceae
Hamameli daceae
Hedeoma pulegoides
Helianthus spp.
Heteranthera dubia
Hibiscus Moscheutos
Hordeum vylgare
Hydrochari taceae
Ilex decidua
Ilex laevigata
Ilex opaca
Ilex spp.
Ilex verticillata
Ipomoea hederacea
Iridaceae
Iris Pseudacorus
Iva frutescens
Juglandaceae
Juncaceae
Juncus spp.'
Juncus Roemerianys
Juniperus virginiana
Labiatae
Leersia oryzoides
Leersia virginica
Leguminosae
Lemna minor
Lemnaceae
Leptochloa fascicularis
Lespedeza bicolor
Lespedeza spp.
nued)
beech
meadow fescue
saltmarsh fimbristylis
saltmarsh fimbristylis
white ash
fui rena
bedstraw> cleavers
geraniurn
wild gerani urn
seaside gerardia
manna grass
soy bean
red weed
grasses
watermiIfoi1
wi tch-hazel
American pennyroyal
sunflower
water star-grass
rose-mallow
barley
frog-bi t
holly
wi nterberry
American holly
holly
black alder (winterberry)
morning glory
iris
water-flag
marsh-elder
walnut
rush
rush
needlerush
red cedar
mi nt
cut grass
white grass
pulse
duckweed
pulse
bush-clover
-------
APPENDIX TABLE A-l. (continued)
Animal food items
Plant food items
Heliosoma trivolvis
Hcmi ptera
Heptagenii dae
Hexagenia bilineata
Hexagenia spp.
Hexapaneopeus angustifrons
Hirudinea
Homoptera
Hyalolla spp.
Hydracarina (Acarina)
Hydrachna spp.
Hydrachni dae
Hydrobia spp. (Littoridinops)
Hydrobi i dae
Hydrophilidae
Hydrophilus spp.
Hydrozoa
Hymenoptera
Ichneumoni dae
Ictalyri dae
Idotei dae
Insecta
Isopoda
Laeyicardium mortoni
Lasius spp.
Lepadidae
Lepas spp.
Lepi doptera
Lcpomis gibbosus
Lepomi s macrochi rus
Lepomis spp.
Leptinotarsa decemlineata
Leptocheirus plumulosus
Leptochelia savigny
L i belluidae
Littorina irrorata
Littorinidae
Lophopodi dae
Lora spp.
Lumbrici dae
Lyci dae
Lycosa spp.
Lycosi dae
Lygaedidae
Lymnaea columella
Lymnaei dae
fresh water snail
true bug
stream mayfly
mayfly
mayfly
mud crab
leech
cicada, hopper* aphid
amphi pod
mi te
freshwater mite
freshwater mite
swamp snail
water scavenger beetle
water scavenger beetle
hydro id
bee, wasp, ant
i chneumoni d
catfi sh
aquatic sowbug
i nsect
isopod
Morton's cockle
fi eld ant
goose barnacle
goose barnacle '
butterfly, moth
bluegi11
bluegill
bluegi11
Colorado potato beetle
amphipod
common skimmer
marsh periwinkle
periwi nkle
bryozoan
lora
net-winged beetle
wolf spider
wolf spider
seed bug
(continued)
Lespedeza stipulacea
Lespedeza striata
Lili aceae
Limonium spp.
Lippia lanceolata
Lippia spp.
Liqyidambar styraciflua
Liriodendron tulipifera
Lolium perenne
Lolium spp.
Ludwigia palustris
Lycopus uniflorus
Lythraceae
Magnolia virginiana
Magnoli aceae
Malvaceae
Medicago lupulina
Melilotus spp.
Mo Hugo vertici lliata
Muhlenbergia frondosa
Muhlenbergia spp.
Myrica carolinensis
Myri ca ceri fera
Myrica pensylvanica
Myrica spp.
Myri caceae
Myriophyllum oxalbescens
Myriophyllum spp.
Myriophyllum spicatum
Nadaceae
Najas flexi1i s
Najas guadalupensis
Najas marina
Najas spp.
Nitella spp.
Nuphar advena
Nymphaea odorata (Castalia)
Nymphaeaceae
Nyssa aquatica
Nyssa biflora
Nyssa spp.
Nyssa sylvatica (biflora)
Nyssaceae
Oleaceae
Onagraceae
Panicum anceps
Korean lespedeza
Japanese clover
lily
sea-lavender
fog-frui t
fog-frui t
sweet gum (red gum)
tulip tree (yellow poplar)
English rye grass
rye grass
marsh-purslane
bugle-weed
loosestri fe
sweet bay (swamp bay)
magnoli a
mallow
black medick
sweet clover
carpet-weed
muhly
wax-myrtle
wax-myrtle
bayberry
wax-myrtle
wax-myrtle
watermiIfoi1
watermiIfoi1
Eurasian watermiIfoi1
naiad
northern naiad
southern naiad
nai ad
nai ad
ni tella
yellow water lily
whi te water lily
water lily
sour gum
water gum
sour gum
black gum (sour gum)
sour gum
ol i ve
evening primrose
panic grass
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food items
Lyrogyrus puporideus
Lyrogyrus spp.
Macoma balthica
Macoma mitchelli (M. phenax)
Macoma tenta
Mactra spp. (Spisula spp.?)
Mactri dae
Melampidae
Melampus bidentatus
Melanella spp. (Eulima)
Melanelli dae
Membranipora spp.
Mernbrani pori dae
Menidia spp.
Microciona prolifera
Mi croci oni dae
Mitrella lunata
Mitrella spp.
Modiolus plicatulis
Modiolus spp. (Volsella)
Molgula manhattensis
Molgula spp.
Moljusca
Mulinia lateralis
Muri ci das
Mya arenaria
Myaci dae
Myrmica spp.
Mytili dae
Hytilus eduli s
Nalsidae
Nassariidae (Nassidae)
Nassarius obsoletus (Nyanassa)
Nassarius spp.
Nassarius trivittatus (Nassa)
Nassarius vibex
Neopanope texana sayi
Nereidae
Nereis spp.
Nerei s succi nea
Neuroptera
Notropis spp.
Nucula proxima
Nucyli dae
Nysius spp.
Odonata
sna i 1
snail
Baltic macoma
Mitchell's clam
narrowed macoma
(winged?) surf clam
surf clam
salt marsh snail
salt marsh snail
snail
snai 1
bryozoan
bryozoan
silverside
red sponge
sponge
crescent mitrella
mi trella
mussel
mussel
sea grape
sea grape
mollusk
duck clam
rock shell
soft-shelled clam
soft-shelled clam
ant
mussel
blue mussel
dog whelk
mud dog whelk
dog whelk
New England dog whelk
mottled dog whelk
mud crab
clam worm
clam worm
clam worm
alderfly, dobsonfly
shiner
hear nut shell
nut shell
dragonfly/ damselfly
(conti nued)
Panicum capillare
Panicum clandestinum
Panicum dichotomiflorum
Panicum spp.
Panicum verrucosum
Panicum virgatum
Paspalum ci1iatifoliurn
Paspalum laeve
Paspalum spp.
Peltandra virginica
Pennisetum spp.
Phaseolus vulgaris
Phytolacca americana
Phytolaccaceae
Pinaceae
Pinus spp.
Pinus Taeda
Plantaginaceae
Plantago lanceolata
Plantago spp.
Plumbagi naceae
Polygonaceae
Polygonum amphibium
Polygonum arifolium
Polygonum avicylare
Polygonum coccineum
Polygonum densiflorum
Polygonum hydropiperoides
Polygonum lapathifoliurn .
Polygonum pensylvanicum
Polygonum punctatum
Polygonum sagittatum
Polygonum scandens
Polygonum spp.
Polygonum virginianum (Tovara)
Polygonum Hydropiper
Polygonum Persicaria
Polypodi aceae
Polystichum acrostichoides
Pontederia cordata
Pontederiaceae
Portulaca oleracea
Portulaca spp.
Portulacaceae
Potamogeton amplifoliys
Potamogeton berchtoldi
witch grass
panic grass
panic grass
panic grass
panic grass
grass
grass
arrow arum
feathertop
common bean
pokeweed
pokeweed
pi ne
pi ne
loblolly pine
plantai n
English plantain
plantai n
leadwort
buckwheat
smartweed
halberdleaf tear-thumb
marsh smartweed
southern smartweed
swamp smartweed
nodding smartweed
smartweed
dotted smartweed
smartweed
false buckwheat
smartweed
smartweed
smartweed
fern
chri stmas-fern
pickerel weed (tuckahoe)
pickerel weed
purslane
purslane
purslane
bigleaf pondweed
slender pondweed
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food
items
Odontomyia spp.
Odostomia impressa
Odostomia spp.
Odostomia trifida
01i gochaeta
Opsanus tau
Orchestia agilis
Orchestia spp.
Orthoptera
Ovalipes ocellatus
Palaemonetes pugio
• Palaemonetes spp.
Palaemonetes vulgaris
Palaemonidae
Paneopeus herbstii
Paneopeus spp.
j\ Pectinatella magnifica
3° Pelecypoda (Bivalvia)
Pentatomi dae
Perca flavescens
Perci dae
Phyllophaga spp.
Physa heterostropha
Physa sayi i
Physa spp.
Physi dae
Phytonomus meles
Phytonomus nigrirostris
Pi sauridae
Pi si di urn alsdi turn
Pisidium atlanticum
Pi si di urn spp.
Pissodes nemorensis
Planorbi dae
Pleurocera spp.
Pleuroceri dae
Pleurotomella spp. (Pleurotoma)
Plumatellina
Podocopa
Poeci1i i dae
Poeciloscleri na
Pogonias cromis
Polistes spp.
Polychaeta
Popillia japonica
Pori fera
incised odostome
odostome
tripartite odostome
aquatic earthworm
oyster toadfish
amphi pod
amphi pod
grasshopper, cricket
lady crab
prawn
grass shrimp
common prawn
prawn and shrimp
.mud crab
mud crab
bryozoan
bi valve
stink bug
yellow perch
perch
June beetle
snai 1
snai 1
snai 1
pouch snai1
lesser clover leaf weevil
fishing spider
fresh-water clam
fresh-water clam
fresh-water clam
orb snai1
river snail
river snail
pleurotomella
ostracod
black drum
paper wasp
polychaete
Japanese beetle
sponge
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Potamogeton
Proserpi naca
crispus
epihydrus
f oli osus
grami neus
natans
nodosus (americanus)
pecti natus
perfoliatus
pusillus
spp.
palustris
(continued)
Prunella vulgaris
Prunus serotina
Prunus virginiana
Quercus palustris
Quercus spp.
Quercus Phellos
Ranunculaceae
Ranunculus acris
Ranunculus bulbosus
Ranunculus sceleratus
Rhamnaceae
Rhodophyceae
Rhus glabra
Rhus radicans
Rhus spp.
Rhus Copallinum
Rhus Toxicodendron
Rhynchospora capitellata
Ricinus communis
Robinia Psuedoacacia
Rosa palustris
Rosa spp.
Rosaceae
Rubiaceae
Rubus spp.
Rumex cri spus
Rumex obtusifolius
Rumex spp.
Rumex verti ci Hi atus
Rumex Acetosella
Ruppi a mari ti ma
Sagittaria latifolia
Sagittaria rigida
Sagittaria spp.
Salicornia Bigelovii (musronata)
curly pondweed
ribbonleaf pondweed
leafy pondweed
variable pondweed
floating pondweed
longleaf pondweed
sago pondweed
redhead grass
slender pondweed
pondweed
marsh mermaidweed
self-heal
wild cherry (black cherry)
choke-cherry
pi n-oak
oak
wi How-oak
crowfoot
buttercup
buttercup
cursed crowfoot
buckthorn
red algae
smooth sumac
poison ivy - poison oak
cashew
sumac
poi son-oak
beak-rush ;
castoi—bean
black locust
swamp rose
rose
rose
madder
bramble
sour dock
bitter dock
dock, sorrel
watei—dock
red sorrel
wi dgeongrass
broadleaf arrowhead
bur arrowhead
arrowhead
glasswort (samphire)
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food items
Portunidae
Pyralidae
Pyrarnidella spp.
Pyramidellidae (Turbinellidae)
Pyrenidae (Columbel1idae)
Rangia cuneata
Reduvii dae
Retusa canaliculata (Acteocina)
Retusi dae
Rhinomacer elongatus
Rhithropaneopeus harrisi
Ri ssoi dae
Sanguinolariidae
Sayella chesapeakea
Scarabaeidae
Sciaenidae
Sesmarma spp.
Siali dae
Si ali s spp.
Sirthenia carinata
Sphaeri dae
Sphaerium spp.
Sphaerium striatinum
Sphaerium transversum
Sphenophorus spp.
Staphylinidae
Stenolophus spp.
Strati ornyi dae
Systena elongata
Tabani dae
Tachistodes spp.
Tagelus plebeius
Tali tri dae
Tanaidae
Tellina spp.
Tellinidae
Tenebri oni dae
Thoracia
Ti puli dae
Tri choptera
Triliarthrus badiipennis
Triphora nigrocincta (Triforis)
Tri phori dae
Tropisternus spp.
Turbinidae
Turbo spp.
swimming crab
pyralid moths
pyramid shell
pyramid shell
dove shell
brackish water clam
assassin bug
channeled barrel bubble
snout beetle
white-fingered mud crab
ri sso
gari shell
snai 1
scarab beetle
alderfly
sphere shell
sphere shell
billbug
rove beetle
soldi er fly
horsefly> deerfly
stout razor clam
beach flea
aquatic sowbug
dwarf tell in
tellin
darkling beetle
barnacle
crane fly
caddi sfly
black triphora
left-handed snail
turban shell
Sambucus canadensis
Scirpus acutus (occidentalis)
Scirpus americanus
Scirpus fluviatilis
Scirpus pallidus
Scirpus purshianus (debilis)
Scirpus robustus
Scirpus spp.
Scirpus validus
Sci rpus Olneyi
Scrophulari aceae
Sccale cereale
Setaria geniculata
Setaria glauca
Setaria italica
Setaria lutescens
Setaria magna
Setaria spp.
Setari a vi ri di s
Setari a Faberi i
Smilax glauca
Smilax rotundifolia
Smilax spp.
Smilax Ualteri
Solanaceae
Solanum carolinense
Solanum nigrum
Sorgum halapense
Sorgum spp.
Sorgum yulgare
Sparganiaceae
Sparganium americanum
Sparganiurn androcladum
Sparganium eurycarpum
Sparganium spp.
Spartina alterniflora (stricta)
Spartina cynosuroides
Spartina patens
Spartina spp.
Spirodela polyrhiza
Stellaria media
Taxodium distichum
Teycrium canadense
Trichostema spp.
Trifolium repens
Triticum aestivum
common-elder
hardstem bulrush
common threesquare
river bulrush
black bulrush
bluntscale bulrush
saltmarsh bulrush
bulrush
softstem bulrush
olney threesquare
fi gwort
rye
foxtail grass
f oxtai1 grass
millet
foxtail grass
giant setaria
foxtai1 grass
foxtail grass
foxtai1 grass
lily
lily
lily
lily
ni ghtshade
horse-nettle
black nightshade
Johnson grass
grass
grass
burreed
easterh burreed
shining burreed
big burreed
burreed
saltmarsh cordgrass
big cordgrass
saltmeadow cordgrass
cordgrass .
big duckweed
chickweed (staruort)
bald cypress
germander (wood sage)
blue curls
white clover
wheat
(continued)
-------
APPENDIX TABLE A-1. (continued)
Animal food items
Plant food items
Turbonilla spp.
Turri dae
Unionidae
Urochordata (Tunicata)
Urosalpinx cinerea
Valvata tricarinata
Valvati dae
Veneridae
Vespa spp.
Vespidae
Vi vi parus
Xanthi dae
intertextus
(Pilumnidae)
Zygoptera
pyramid shell
turret shell
fresh water clarn
Atlantic oyster drill
round-mouth snaiil
hard-shelled clam
paper wasp
mud crab
damselfly
Ulmaceae
Ulva lactuca
Diva spp.
Ulvaceae
Umbel1i ferae
Urti caceae
Vallisneria americana (spiralis)
Verbena urticifolia
Verbenaccae
Vi ci a spp.
Vigna sinensis
Vi taceae
Vitis aestivalis
Vi ti s ri pari a
Vitis spp.
Vitis vulpina (cordifolia)
Xanthium spp.
Zannichellia palustris
Zea mays
Zizania aquatica
Zizaniopsis miliacea
Zostera marina
Zosteraceae
elm
sea lettuce
sea lettuce
sea lettuce
parsley
nettle
MiIdcelery
verva i n
vervai n
vetch
coN-pea
grape
summer-grape
forest-grape
grape, wild grape
forest-grape
cocklebur
horned pondweed
corn
Mi Idri ce
southern wild rice
eelgrass
pondweed
-------
APPENDIX TABLE B-1. FOOD ITEMS OF WHISTLING SWANS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
3.
Frequency occurrence Aggregate percent
Scientific name
Mollusca
Sayella chesapeakea
Pelecypoda (Bivalvia)
Nacoma balthica
Macoma mitchelli (M. phenax)
Mya arenaria
Tagelus plebeius
Polychaeta
Nereis spp.
Arthropoda
Isopoda
Cyathura carinata (polita)
Amphi poda
Decapoda
Ovalipes ocellatus
Rhodophyceae
Enteromorpha spp.
Potamogeton pectinatus
Potamogeton perfoliatus
Sparganium eurycarpum
Cladi urn mar isco ides
Scirpus americanus
Scirpus Olneyi
Scirpus robustus
Zea mays
Distichlis spicata
Myrica spp.
Rumex spp.
Polygonum punctatum
Rhus Copallinum
Nyssa sylvatica (biflora)
Ceratophyllum demersum
Ruppia maritima
Vallisneria americana (spiralis)
Scirpus spp.
Gizzard Gullet Unknown Gizzard
Common name (2) ( .) ( 50) ( 2)
mollusk . 6
snai 1
bi valve
Baltic macoma
Mitchell's clam
soft-shelled clam
stout razor clam
polychaete
clam worm
i sopod
isopod
scud, sideswimmer
crayfish, shrimp
lady crab
2
4
34
4
28
2
4
12
2
2
4
4
2
2
Total animal material 0 . 64 .
red algae . 4
filamentous green algae
sago pondweed
redhead grass
big burreed
twi g-rush
common threesquare
olney threesquare
saltmarsh bulrush
corn
salt grass
wax-myrtle
dock, sorrel
dotted smartweed
sumac
black gum (sour gum)
hornwort
undetermined vegetation
2
22
12
2
.2
4
2
2
10
2
2
2
2
2
4
2
6
widgeongrass 50 . 76 50.0
wildcelery 50 . 6 49.5
bulrush 50 . 2 0.5
Total plant material 100 . 96 100.0
Gullet Unknown
( .) ( 50)
0. 1
0.0
0.0
16.8
1.7
6.4
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
25.3
0.0
0.2
6.2
2.3
0.0
0.0
0. 1
0. 1
0.0
6. 1
1.0
0.0
0.0
0. 1
0.0
0.8
0.0
1.3
48.7
5.9
1.9
74.7
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-2. FOOD ITEMS OF RUDDY DUCKS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Frequency occurrence
Sci enti f i c name
Bittium varium
Laevicardium mortoni
Mya arenaria
Cyathura carinata (polita)
Chiridotea caeca
Gammarus mucronatus
Macoma balthica
Retusa canaliculate (Acteocina)
Mulinia lateralis
Macoma mitchelli (M. phenax)
Tellina spp.
Amphipoda
Paneopeus herbsti i
Arthropoda
Chi ronomi dae
Crangon spp.
Mollusca
Gemma gemma
Sayella chesapeakea
Nereidae
Gyralus parvus (Planorbis)
Paneopeus spp.
Trichoptera
Sial i dae
Arcuatula demissa (Volsella)
Hydrobia spp. (Li ttor i di nops)
Pelecypoda (Bivalvia)
Gyralus spp. (Planorbis spp.)
Ell i pt i o spp.
Insecta
Cor i xi dae
Myrmica spp.
Gastropoda
Nereis spp.
Coleoptera
Scarabaei dae
Enochrus spp.
Formi ci dae
Anisoptera
Ephemeri dae
Hydrachni dae
Common name
variable bittium
Morton's cockle
soft-shelled clam
i sopod
i sopod .
scud
Baltic macoma
channeled barrel bubble
duck clam
Mitchell's clam '
undetermined fish
dwarf tell in
scud, sideswimmer
mud crab
mi dge
sand shrimp
mollusk
gem clam
snai 1
clam worm
fresh water snail
mud crab
caddi sf ly
alderf ly
Atlantic ribbed mussel
swamp snail
bi valve
i nsect
water boatman
ant
snail, limpet
clam worm
beetle
scarab beetle
ant
dragonfly
burrowing mayfly
freshwater mite
Gizzard Gullet
( 25) ( .)
^ t
, .
, .
. .
t t
20
8
T •
4
12
8
4
4
16
20
4
20
4
8
16
^
-------
APPENDIX TABLE B-2. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent6
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 25) ( .) ( 10) ( 25) ( .) ( 10)
Pori fera
Bryozoa (Ectoprocta)
Coelenterata (Cnidaria)
sponge
hydroid, jellyfish
8
4
0.0
0.0
0.0
Nyssa sylvatica (biflora)
Vallisneria americana (spiralis)
Sci rpus Olneyi
Zea mays
Ruppia maritima
Potamogeton pectinatus
Polygonum hydropi peroi des
Agrostemma Githago
Paspalum spp.
Potamogeton spp.
Potamogeton perfoliatus
Potamogeton pusillus
Najas guadalupensi s
Avena fatua
Scirpus validus
Grami neae
Cladium mariscoides
Scirpus robustus
Carex spp.
Chara spp.
Scirpus spp.
Distichlis spicata
Sambucus canadensis
Eleocharis palustris
Panicum spp.
Myrica cerifera
Polygonum punctatum
Myriophyllum spp.
Cuscuta spp.
-
Total animal material
black gum (sour gum)
wi Idcelery
olney threesquare
corn
wi dgeongrass
undetermined vegetation
sago pondweed
swamp smartweed
corn-cockle
grass
pondweed
redhead grass
slender pondweed
southern naiad
wild oat
softstem bulrush
grasses
twi g-rush
saltmarsh bulrush
sedge
muskgrass
bulrush
salt grass
common-elder
common spikerush
panic grass
wax-myrtle
dotted smartweed
watermi If oi 1
dodder
Total plant material
80
.
24
24
12
28
36
8
4
12
4
20
8
8
4
4
8
8
4
4
8
4
4
4
4
4
4
4
4
4
4
88
80
20
. .
20
30
20
10
.
.
.
.
.
20
10
10
. - .
. .
. .
• *
10
.
. .
.
. .
. .
. .
. .
. .
. .
. .
. •
90
34.8
f
21.3
10.4
8.7
8.3
5.3
2.5
2.4
1.9
1.4
0.8
0.5
0.4
0.4
0.3
0. 1
0. 1
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
65.2
67.5
0.9
.
0.5
19.3
0.5
1.0
.
.
.
.
.
2.8
0.5
7. 0
. .
. .
.
.
0.0
•
.
.
.
. .
.
.
.
.
.
•
32.5
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-3. FOOD ITEMS OF BUFFLEHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet
(6) ( .)
Unknown
( 20)
Gizzard Gullet
(6) ( .)
Unknown
( 20)
Ri ssoi dae
Sayella chesapeakea
Odostomia impressa
Ratusa canaliculata (Acteocina)
Nassarius trivittatus (Nassa)
Lora spp.
Mytili dae
Brachiodontes recurvus (Mytilus)
Arcuatula demissa (Volsella)
Modiolus spp. (Volsella)
Gemma gemma
Mulinia lateralis
Macoma balthica
Macoma mitchelli (M. phenax)
Mya arenaria
Nerei s spp.
Cyathura spp.
Cyathura carinata (polita)
Erichsonella spp.
Chiridotea caeca
Amphi poda
Gammaridae ,
Decapoda
Paneopeus herbstii
Balanus spp.
Curculi oni dae
Goniobasis virginica
Hexapaneopeus angustifrons
Crangon spp.
Arthropoda
Isopoda
Hexagenia spp.
Heliosoma trivolvis
Amnicola spp.
Pelecypoda (Bivalvia)
Mollysca
Bittium alternatum (B, nigrum)
Mitrella spp.
Gastropoda
risso
snai 1
incised odostome
channeled barrel bubble
New England clog whelk
lora
mussel
hooked mussel
Atlantic ribbed mussel
mussel
gem clam
duck clam
Baltic macoma
Mitchell's clam
soft-shelled clam
clam worm
isopod
i sopod
i sopod
i sopod
scud, si deswiminer
scud
crayfish, shrimp
mud crab
barnacle
snout beetle
undetermined fish
snai 1
mud crab
sand shrimp
i sopod
mayfly
fresh water snail
amni cola
bivalve
mollusk
alternate bittium
mi trella
snail, limpet
Total animal material
17
17
17
17
17
17
17
17
17
17
17
17
17
83
10
5
25
15
5
5
5
20
5
5
30
25
35
10
5
35
5
5
10
5
15
10
15
25
30
5
15
0. 1
0.0
15.8
6.7
5.8
3.3
3.3
3.3
2.2
,0
,0
2.
2.
1.7
0.3
0.8
0.0
4.4
9.6
4.4
1.3
0.5
0.3
0.0
0.3
2.3
0. 1
5.8
4.5
0.0
13.3
15. 1
0.0
5.5
95
0.2
47.0
0. 1
75.3
(continued)
-------
APPENDIX TABLE B-3. (continued)
Scientific name
Zosteraceae
Zostera marina
Najas guadalupensi s
Zea mays
Distichlis spicata
Ruppia maritima
Potamogeton spp.
Vallisneria atnericana (spiralis)
Potamogeton perfoliatus
Polygohum arifolium
Common name
pondweed
eelgrass
southern naiad
corn
salt grass
wi dgeongrass
pondweed
wi Idcelery
undetermined vegetation
redhead grass
halberdleaf teai — thumb
Total plant material
Frequency occurrence
Gizzard Gullet Unknown
(6) ( .) (20)
5
,
. .
.
.
33
50
17
33
17
17
10
5
25
5
60
.
.
5
25
•
83 . 85
•» o
Aggregate percent
Gizzard
( 6)
.
.
.
.
19.2
18.0
8.3
5.5
1.2
0.8
53.0
Gullet Unknown
( .) ( 20)
0.0
5.0
0.0
12.6
0.0
6. 1
. *
. •
0.0
0.9
•
24.6
Ln
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-4. FOOD ITEMS OF COMMON GOLDENEYES IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Frequency occurrence
Aggregate percent*
Common name
Gizzard Gullet
( 14) ( .)
Unknown
( 12)
Gizzard Gullet
( .)
Unknown
( 12)
Sayella chesapeakea
Goniobasis virginica
Heliospma spp. (Planorbis spp.)
Gyralus parvus (Planorbis)
Odostomia impressa
Nassarius trivittatus (Nassa)
Gi Hi a alti 1 i s
Brachiodontes recurvus (Mytilus)
Arcuatula demissa (Volsella)
Mulinia lateralis
Macoma balthica
Nereis spp.
Gammaridae
Callinectus sapidus
Paneopeus herbstii
Paneopeus spp.
Sesmarma spp.
Pelecypoda (Bivalvia)
Mollusca
Tri choptera
Lasius spp.
Nassarius obsoletus (Nyanassa)
Crangon spp.
Cancer borealis •
Anachi s avara
Melanella spp. (Eulima)
Mactra spp. (Spisula spp.?)
Apeltes quadracus
Cambarus diogenes
Neopanope texana sayi
Arthropoda
Veneridae
Gastropoda
Nereidae
Cyprini dae
Uni oni dae
Insecta
Ani soptera
Bittium spp.
Mitrella spp.
Retusa canaliculata (Acteocina)
snaj 1
snail
orb snai1
fresh water snail
i nci sed odostome
New England dog whelk
snai 1
hooked mussel
Atlantic ribbed mussel
duck clam
Baltic macoma
clam worm
scud
blue crab
mud crab
mud crab
undetermined fish
bivalve
mollysk
caddi sfly
field ant
mud dog whelk
sand shrimp
northern crab
greedy dove shell
snail
(winged?) surf clam
mud c'rab
hard-shelled clam
sna il> 1impet
clam worm
mi nnow
fresh water clam
insect
dragonfly
mitrella
channeled barrel bubble
(conti nued)
29
43
7
7
7
7
7
7
7
7
7
7
14
21
7
14
29
7
7
7
7
21
21
14
17
8
8
8
8
17
8
33
25
8
17
25
17
17
58
8
8
25
8
17
7.8
5.5
5.4
5.3
3.8
2.9
2.6
1.8
1.8
1.4
1. 1
1.0
0.9
0.8
0.6
0.6
0.4
0.4
0.4
0.4
0.4
0.3
0.3
0. 1
.3
.3
0.0
1.0
8.3
0.3
0.0
0
0
2.9
5.0
4.2
1.3
0.0
4.6
0.0
17. 1
4.2
5.4
6.3
0.0
7.7
-------
APPENDIX TABLE B-4. (continued)
Frequency occurrence Aggregate percent
Scientific name
Nassarius vibex
Bittium alternatum (B. nigrum)
Balanidae
Caralsi dae
Tachistodes spp.
Stenolophus spp.
Phytonornus nigrirostris
Rhinomacer elongatus
Euparius marmoreus
Eros spp.
Nalsidae
Hymenoptera
Ichneumoni dae
Crepidula convexa
Gemma gemma
Anneli da
Isopoda
Amphipoda
Pissodes nemorensis
Chrysomel i dae
Systena elongata
Bethyli dae
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 14) ( .) ( 12) ( 14) ( .) ( 12)
mottled dog whelk
alternate bittium
rock barnacle
lesser clover
snout beetle
bee, wasp, ant
i chneumoni d
convex slipper
gem clam
leaf weevil
shell
7 . . 0.
7 . . 0.
21 . . 0.
7 . . 0.
7 . . 0.
7 . . 0.
7 . . 0.
7 . . . 0.
7 . . 0.
7 . .0.
7 . . 0.
7 . . 0.
7 . . 0.
• •
• •
. .
. »
. .
• • •
• •
. .
• •
7 . . 0.0
21 . 8 0.0 0.0
leech, polychaete
i sopod
7 . . 0.0
7 . 25 0.0 . 10. 4
scud, sideswimmer
7 . 8 0.0 0.8
7 0.0
leaf beetle
7 0.0
7 . . 0.0
bethylid
7 0.0
Total animal material
Potamogeton perfoliatus
Zea mays
Potamogeton spp.
Elodea canadensis
Vallisneria americana (spiralis)
Ruppia maritima
Charophyceae
Zostera marina
redhead grass
corn
86 . 100 46.9 . 82.9
8
0.3
43 . 33 24.6 . 8.3
undetermined vegetation
pondweed
common elodea
wi Idcelery
wi dgeongrass
79 .8 8.4 . 0.4
21 . 8 7.8 3.3
7 . . 7.1
.
7 . . 4.9
7 . 25 0.3 . 3.9
muskgrass, stonewort
eelgrass
Total plant material
7 . . 0.1
7 . 8 0.1
93 . 67 53.1
.
0 .8
17. 1
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-5. FOOD ITEMS OF CANVASBACKS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 47) ( 2)
Unknown
( 52)
Gizzard Gullet
( 47) ( 2)
Unknown
( 52)
•vl
CD
Sayella chesapeakea
Bi tti urn vari urn
Triphora nigrocincta (Triforis)
Mitrella lunata
Odostomia impressa
Nassarius trivittatus (Nassa)
Hydrobia spp. ( Littoridinops)
Brachiodontes recurvus (Mytilus)
Arcuatyla demissa (Volsella)
Congeria leucophaeta
Laevicardium mortoni
Gemma gemma
Mulinia lateral]s
Macoma mitchelli (M. phenax)
Mya arenaria
Nereis spp.
Cyathura spp.
Cyathura carinata (polita)
Erichsonella spp.
Amphi poda
Gammarus mucronatus
Callinectus sapidus
Ovalipes ocellatus
Xanthidae (Pilumnidae)
Paneopeus herbstii
Pelecypoda (Bivalvia)
Macoma balthica
Polychaeta
Mollusca
Nerei dae
Hexaqenia spp.
Rhithropaneopeus harrisi
Mactra spp. (Spisula spp.?)
Nassariidae (Nassidae)
Retusa canaliculata (Acteocina)
Nassarius vibex
Gastropoda
Pyramidellidae (Turbinellidae)
Anneli da
Dccapoda
Neopanope texana sayi
Ri ssoi dae
snai 1
variable bittium
black triphora
crescent mitrella
incised odostome
New England dog whelk
swamp snai1
hooked mussel
Atlantic ribbed mussel
Conrad's false mussel
Morton's cockle
gem clam
duck clam
Mitchell's clam
soft-shelled clam
clam worm
i sopod
i sopod
i sopod
scud, sideswimmer
scud
blue crab
lady crab
mud crab
mud crab
bivalve
Baltic macoma
polychaete
mollusk
clam worm
mayfly
white-fingered mud crab
(winged?) surf clam
dog whelk
channeled barrel bubble
mottled dog whelk
snail; limpet
pyramid shell
leech, polychaete
crayfish, shrimp
mud crab
ri sso
(continued)
17
6
6
13
9
4
2
2
2
4
4
6
2
2
2
2
2
50
100
8
10
2
2
12
2
6
6
4
2
2
8
19
4
4
19
2
2
8
2
2
25
2
2
23
6
60
2
6
8
4
13
0.2
0.8
9.7
6.4
5.2
4.9
1.3
0.4
0.2
0
0
0
0
0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.2
0.0
0
5.9
0. 1
0.8
0.0
0.0
0.2
1.6
0.0
0. 1
2. 1
0.2
0.8
5.6
2.4
26.5
0.8
0.8
0.6
o! i
-------
APPENDIX TABLE B-5. (continued)
VO
Scientific name
Bittium spp.
Mitrella spp.
Odostomia spp.
Caralsi dae
Tr i choptera
Pori f era
Common name
mi trella
odostome
caddi sf ly
sponge
Frequency occurrence
Gizzard Gullet Unknown
( 47) ( 2) ( 52)
4
2
2
2
2
2
Aggregate percent3
Gizzard
( 47)
0.0
0.0
0.0
0.0
0.0
0.0
Gullet Unknown
( 2) ( 52)
» •
'.
• •
, .
.
•
Total animal material
49
100
87
28.7
1.0
52.7
Najas guadalupensi s
Sparganium eurycarpum
Cladium mariscoides
Scirpus Olneyi
Scirpus robustus
Chenopodium spp.
Vallisneria americana (spiralis)
Potamogeton pectinatus
Zea mays
Potamogeton perfoliatus
Scirpus spp.
Sagittaria spp.
Potamogeton spp.
Zostera marina
Ruppia maritima
Panicum virgatum
Agrostemma Githago
Prunus virginiana
Rhus radicans
Charophyceae
Cyperaceae
Rumex spp.
southern naiad
big burreed
twi g-rush
olney threesquare
saltmarsh bulrush
goosef oot
woody bark fragments
wi Idcelery
sago pondweed
undetermined vegetation
corn
redhead grass
bulrush
arrowhead
pondweed
eelgrass
wi dgeongrass
panic grass
corn-cockle
choke-cherry
poison ivy - poison oak
muskgrass, stonewort
sedge
dock, sorrel
Total plant material
. .
.
. .
.
.
. .
.
34 100
23
34
13
17
2 50
2
11 100
6
4
2
2
2
2
2
2
2
79 100
2
2
2
4
2
2
2
4
4
2
25
52
.
.
.
21
60
.
.
.
.
.
2
•
94
.
.
.
.
.
.
.
27. 1
15.8
12.7
7. 1
4.2
2. 1
1.6
0.4
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
71.3
0.0
0.2
0.0
0.0
0.0
0.0
1.3
99.0 3.8
0. 1
0.6
12.6
15.8
0.0 .
.
0.0
8.2
4.6
.
.
.
.
.
0.0
•
99.0 47.3
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-6,
FOOD ITEMS OF GREATER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1890
Frequency occurrence
1959
3
Aggregate percent
Scientific name
Common name;
Gizzard Gullet Unknown
( 36) ( 2) ( 14)
Gizzard Gullet
( 36) ( 2)
Unknown
(
oo
o
Sayella chesapeakea
Odostomia impressa
Nassarius obsoletus (Nyanassa)
Macoma balthica
Nereis spp.
Callinectus sapidus
Coelenterata (Cnidaria)
Gastropoda
Mollusca
Goniobasis virginica
Gemma gemma
Pelecypoda (Bivalvia)
Mulinia lateralis
Amnicola spp.
Anachis avara
Rhithropaneopeus harrisi
Brachiodontes recurvus (Mytilus)
Mitrella lunata
Bittium alternatum (B. nigrum)
Laevicardium mortoni
Decapoda
Turbonilla spp.
Nassarius vibsx
Odostomia spp.
Amnicola limosa
Bittium spp.
Bittium varium
Cerithopsis spp.
Pyramidella spp.
Nassarius trivittatus (Nassa)
Pleurotomella spp. (Pleurotoma)
Retusa canaliculata (Acteocina)
Mitrella spp.
Gammarus fasciatus
Neopanope texana sayi
Triphora nigrocincta (Triforis)
Ri ssoi dae
Balani dae
Lycosa spp.
Odostomia trifida
Nerei dae
Xanthidae (Pilumnidae)
snai 1
incised odostome
mud dog whelk
Baltic macoma
clam worm
blue crab
hydroid, jellyfish
snail, limpet
mollusk
snai 1
gem clam
bi valve
duck clam
amnicola
greedy dove shell
white-fingered mud crab
hooked mussel
crescent mitrella
alternate bittium
Morton's cockle
crayfish, shrimp
pyramid shell
mottled dog whelk
odostome
variable bittium
ceri th
pyramid shell
New England dog whelk
pleurotomella
channeled barrel bubble
mi trella
scud
mud crab
black triphora
r i sso
rock barnacle
wolf spider
tripartite odostome
clam worm
mud crab
(conti nued)
25
17
14
14
14
6
3
14
3
8
11
11
3
3
3
11
14
3
6
3
3
3
3
8
11
6
3
6
6
3
3
3
3
3
3
50
50
100
50
29
36
21
29
7
7
29
7
14
29
7
•
57
36
36
14
14
8.9
8.2
6. 1
3.4
3.4
2.8
2.8
2.7
2.6
2.4
2.2
2.0
1.7
1.7
1.4
1.3
1.0
0.9
0.7
0.6
0.6
0.3
0.2
0.2
0.2
0.0
0.0
0.0
0.0
0.0
0.0
35.0
2.5
20.0
0. 1
0.0
5.4
2. 1
0.0
0.0
0.7
2K8
25.0 7.1
0.7
1
1K2
b,2
(>'.&
0.7
O.l
-------
APPENDIX TABLE B-6. (continued)
oo
Scientific name
Vallisneria americana (spirali
Potamogeton spp.
Zea mays
Ruppia maritima
Zostera marina
Scirpus spp.
Potamogeton pectinatus
Sagittaria spp.
Paspalum laeve
Potamogeton perfoliatus
Najas marina
Rhus glabra
Centella erecta (asiactica)
Fimbristylis spp.
Rhus spp.
a
As defined by Swanson et al.
Common name
Total animal material
s) wildcelery
pondweed
corn
wi dgeongrass
eelgrass
undetermined vegetation
bulrush
sago pondweed
arrowhead
grass
redhead grass
naiad
smooth sumac
parsley
saltmarsh fimbristylis
cashew
Total plant material
(1974).
Frequency occurrence
Gizzard Gullet • Unknown
( 36) ( 2) ( 14)
92 100 100
39
22 50
11 . 21
31 . 36
6 . 57
8
3
3 . .
3
3
3
3
3
3
3
3
86 50 86
Aggregate pe
Gizzard Gullet
( 36) ( 2)
59.6 82.5
16.3
7.6 17.5
6.8
3.2
2.0
1.6
0.8
0.6
0.6
0.6
0.2
0.0
0.0
0.0
0.0
0.0
40.4 17.5
rcent
Unknown
( 14)
67.3
*
.
12.4
7.8
12.5
.
;
.
.
.
• .
.
.
.
.
•
32.7
-------
APPENDIX TABLE B-7,
FOOD ITEMS OF LESSER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Frequency occurrence
Scientific name
Common name
Aggregate percent
Gizzard Gullet • Unknown
( 29) ( .) ( 29)
Gizzard Gullet Unknown
( 29) ( .) ( 29)
oo
NJ
Sayella chesapeakea
Bi tti urn var i urn
Triphora nigrocincta '(Triforis)
Odostomia impressa
Nassarius trivittatus (Nassa)
Hydrobia spp. (Littoridinops)
Brachiodontes recuryus (Mytilus)
Macoma balthica
Macoma mitchelli (M. phenax)
Mya arenaria
Nereis spp.
Chiridotea caeca
Amphipoda
Gammarus mucronatus
Ovalipes ocellatus
Podocopa
Curculi oni dae
Coelenterata (Cnidaria)
Gastropoda
Amnicola spp.
Goniobasis virginica
Gillia altilis
Amnicola limosa
Arcuatula demissa (Volsella)
Mollusca
Pelecypoda (Bivalvia)
Bittium alternatum (B. nigrum)
Uni oni dae
Anculosa spp.
Gyralus parvus (Planorbis)
Valvata tricarinata
Bittium spp.
Heliosoma spp. (Planorbis spp.)
Nassarius obsoletus (Nyanassa)
Mitrella lunata
Odostomi a spp.
Gemma gemma
Elliptic complanata (Unio)
Mulinia lateralis
Sphaerium spp.
Daphni dae
Tri choptera
snai 1
variable bittium
black triphora
incised odostome
New England dog whelk
swamp snai1
hooked mussel
Baltic macoma
Mitchell's clam
soft-shelled clam
clam worm
i sopod
scud, sideswimmer
scud
lady crab
ostracod
snout beetle
hydroid, jellyfish
snai1> limpet
amni cola
snai 1
sna i 1
Atlantic ribbed mussel
mollusk
bivalve
alternate bittium
fresh Mater clam
river snail
fresh water snail
orb snail
mud dog whelk
crescent mitrella
odostome
gem clam
duck clam
sphere shell
water flea
caddi sfly
(continued)
55
10
31
10
7
3
14
28
3
7
3
3
3
7
10
3
10
10
7
3
7
3
3
10
24
14
31
10
10
38
24
10
10
7
14
10
17
7
7
3
7
3
28
45
8.7
6.9
6.4
4.3
3.4
3.4
3. 1
2.7
2. 1
1.6
0.6
0.6
0.6
0.6
0.6
0.
0,
0.
0,
0,
0.2
0.2
0.2
0. 1
,5
.3
.3
.3
.3
2.0
1.5
3. 1
1.3
0.8
0.0
3.4
5.2
3. 1
1.7
0.0
1.6
0.3
3.6
0.3
0.0
0. 1
0.0
0.0
0.3
0.2
2. 6
-------
APPENDIX TABLE B-7. (continued)
oo
CO
Frequency occurrence
Scientific name
Crepidula spp.
Neopanope texana sayi
Ri ssoi dae
Gyralus spp. (Planorbis spp.)
Retusa canaliculata (Acteocina)
Crangonyx spp.
Decapoda
Crepidula convexa
Modiolus spp. (Volsella)
Mactra spp. (Spisula spp.?)
Nerei dae
Balani dae
Pyrami delli dae (Turbi nell i dae)
Myti 1 i dae
Laevicardium mortoni
Xanthidae (Pilumnidae)
Cumacea
Insecta
For mi ci dae
Pinus Taeda
Potamogeton pectinatus
Cladium mariscoides
Scirpus Olneyi
Scirpus robustus
Distichlis spicata
Myrica spp.
Polygonum pensyl vani cum
Polygonum punctatum
Nyssa sylvatica (biflora)
Iva frutescens
Zea mays
Vallisneria americana (spiralis)
Vi t i s spp.
Ruppia maritima
Potamogeton perfoliatus
Potamogeton spp.
Sagittaria spp.
Potamogeton pusillus
Zostera marina
Na jas f lexi 1 i s
Sci rpus spp.
Common name
slipper shell
mud crab
ri sso
channeled barrel bubble
amphi pod
crayfish, shrimp
convex slipper shell
mussel
(winged?) surf clam
clam worm
rock barnacle
pyramid shell
mussel
Morton's cockle
mud crab
i nsect
ant
Total animal material
loblolly pine
sago pondweed
twi g-rush
olney threesquare
salt marsh bulrush
salt grass
wax-myrtle
smartweed
dotted smartweed
black gum (sour gum)
marsh-elder
corn
undetermined vegetation
wi Idcelery
grape, wild grape
wi dgeongrass
redhead grass
pondweed
arrowhead
slender pondweed
eelgrass
northern naiad
bulrush
Total plant material
Gizzard Gullet
( 29) ( .)
7
7
7
3
10
3
7
3
3
3
10
7
3
3
3
3
3
3
3
90
.
* •
. .
.
. .
• *
• *
. .
.
. .
, ,
31
52
7
3
24
14
14
3
7
10
7
14
83
Unknown
( 29)
.
10
.
52
.
7
.
,
.
.
w
.
,
21
.
t
f
•
97
3
3
3
28
7
3
3
3
3
7
7
38
7
.
.
48
21
.
.
.
7
.
•
93
Aggregate
percent
Gizzard Gullet Unknown
( 29) ( .) (29)
0.
0.
0.
0.
0.
0.
0.
0.0
0.0
0.0
0,0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
48.6
^ a
.
.
.
. .
.
.
. .
.
. .
. .
19.5
6.7
6.1
3.4
3.4
3.4
2.9
2.3
1.4
1.1
0.8
0.4
51.4
'
3.6
.
12.0 .
.
0.0
.
•
.
.
.
.
.
5.2
.
.
.
•
68.0
0. 1
0.2
0.0
0.8
0.0
0.0
0.0
0.0
0.0
0.3
0.0
16.8
0.5
.
.
4.2
5.5
.
.
.
3.6
.
•
32.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-8. FOOD ITEMS OF RING-NECKED DUCKS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
oo
Scientific name
Brachi odontes recurvus (Mytilus)
Gemma gemma
Mulinia lateralis
Macoma balthica
Goniobasis virginica
Mollusca
Insecta
Tri choptera
Pelecypoda (Bivalvia)
Valvata tricarinata
Gastropoda
Daphnia spp.
Ruppia maritima
Potamogeton perfoliatus
Potamogeton epihydrus
Sparganium americanum
Sparganium eurycarpum
Scirpus americanus
Scirpus fluviatilis
Sci rpus Olneyi
Sci rpus val i dus
Carex spp.
Carex lurida
Carex crinita
Echinochloa crusgalli
Echinochloa Walteri
Paspalum laeve
Spartina alterniflora (stricta)
Peltandra virginica
Pontederia cordata
Smi lax spp.
Carpinus caroliniana
Acnida cannabinus (amaranthus)
Polygonum spp.
Polygonum ari folium
Polygonum punctatum
Geranium spp.
Rubus spp.
Lespedeza stipulacea
Rhus spp.
Ilex spp.
Frequency occurrence
Gizzard Gullet Unknown
Common name (17) ( .) (7)
hooked mussel . . 14
gem clam . . 14
duck clam . . 14
Baltic macoma . . 14
snai 1 35 ..
mollusk 24
insect 12
caddi sfly 12
bi valve 6 . 14
6
snail* limpet 6
water flea 6 . .
Total animal material 82 . 29
widgeongrass . 29
redhead grass
ribbonleaf pondweed
eastern burreed
big burreed
common thre.esquare
river bulrush
olney threesquare
softstem bulrush
sedge
sedge
sedge
barnyard grass
grass
saltmarsh cordgrass
arrow arum
pickerel weed (tuckahoe)
lily
hornbeam (blue beech)
tidemarsh waterhemp
smartweed
halberdleaf teai — thumb
dotted smartweed
wild gerani urn
bramble
Korean lespedoza
cashew
holly
29
14
43
14
14
29
14
29
14
14
14
14
14
14
14
29
29
14
14
14
14
14
43
14
14
14
29
14
(continued)
*a
Aggregate percent
Gizzard Gullet Unknown
( 17) ( .) (7)
0.7
0.3
10.7
0.4
32.4
1.0
0.6
0.4
0.2 . 1.4
0.1
0.1
0.0
34.6 . 13.6
13.6
1.4
0.0
1.7
0.3
0.0
0.4
0.6
0. 1
0.0
0.0
• o.o
0.0
0.0
0.0
0.0
17.6
0.4
0.0
0.0
0.0
0.0
4.3
17. 1
0.0
0.0
0.0
0.0
0.7
-------
APPENDIX TABLE B-8. (continued)'
00
Ln
Scientific name
Cornus spp.
Cuscuta spp.
Nuphar advena
Potamogeton spp.
Na jas flexi 1 i s
Potamogeton pusi llus
Potamogeton pectinatus
Vallisneria americana (spiralis)
Characeae
Najas spp.
Cladium mariscoides
Scirpus pallidus
Zea mays
Common name
dogwood
dodder
yellow water li ly
pondweed
northern naiad
undetermined vegetation
slender pondweed
sago pondweed
Mi Idcelery
muskgrass
nai ad
twi g-rush
black bulrush
corn
Total plant material
Frequency occurrence Aggregate percent
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 17) ( .) ( 7) ( 17) ( .) (7)
14 . 0.0
29 . 0.3
14 . 2.1
53 40.7
29 8.8
47 7.2
24 3.1
12 2.8
6 2.1
6 0.5
6 0.1
6 29 0.1 0.0
12 . 0.1
6 29 0.0 25.7
88 . 100 65.4 . 86.4
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-9. FOOD ITEMS OF REDHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Frequency
Scientific name
Gi
Common name (
zzard
10)
occurrence
Gullet
( 3)
• Unknown
( 86)
Aggregate percent
Gi zzard
( 10)
Gullet
( 3)
Unknown
( 86)
00
Physa heterostropha
Bittium spp.
Bi tti urn vari urn
Bittium alternatum (B. nigrum)
Heliosoma spp. (Planorbis spp.)
Heliosoma antrosa (Planorbis)
Gyralus spp. (Planorbis spp.)
Triphora nigrocincta (Triforis)
Odostomia spp.
Odostomia impressa
Retusa canaliculata (Acteocina)
Nassarius obsoletus (Nyanassa)
Hydrobia spp. (Littoridinops)
Amnicola limosa
Valvata tricarinata
Pelecypoda (Bivalvia)
Mytili dae
Congsria leucophaeta
Gemma gemma
Macoma balthica
Mya arenaria
Pi si di um alsdi turn
Nereis spp.
Isopoda
Erichsonella spp.
Amphipoda
Decappda
Xanthi dae
Paneopeus
Balani dae
Cypris spp.
Halipii dae
Tri choptera
Cori xi dae
Hydrachna spp
Gastropoda
Mollusca
Rhodophyceae
Ulva spp.
Ulva lactuca
Characeae
(Pilumnidae)
herbsti i
snai 1
variable bittiym
alternate bittium
orb snail
black triphora
odostome
inci sed odostome
channeled barrel bubble
mud dog whelk
swamp snail
bivalve
mussel
Conrad's false mussel
gem clam
Baltic macoma
soft-shelled clam
fresh-water clam
clam worm
i sopod
isopod
scud, sideswimmer
crayfish, shrimp
mud crab
mud crab
rock barnacle
seed shrimp
crawling water beetle
caddi sf ly
water boatman
freshwater mite
snail, limpet
mollusk
Total animal material
red algae
sea lettuce
sea lettuce
muskgrass
(conti nued)
67
33
33
33
67
33
67
20
10
30
33
67
67
67
67
67
1
1
2
1
1
1
2
5
1
3
2
2
3
2
7
7
2
1
5
1
1
6
24
5
1
6
0.3
0. 1
0.7
1.7
0.3
3.7
0.0
0.3
0.3
0.0
0.0
0.0
o!o
7.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0. 1
o!o
0.0
0.2
0.1
0.0
0.0
0.3
0.0
0.0
o!o
1.0
0.0
0.4
2.3
-------
APPENDIX TABLE B-9. (continued)
oo
_ _ ^
Frequency occurrence Aggregate percent1
Gizzard Gullet Unknown Gizzard Gullet Unknown
Scientific name Common name ( 10) ( 3) ( 86) ( 10) ( 3) ( 86)
Chara spp. muskgrass
Zosteraceae pondweed
Zostera marina eelgrass
Zannichellia palustris horned pondweed
Najas guadalupensi s southern naiad
Najas marina naiad
Elodea canadensi s common elodea
Cyperaceae sedge
Scirpus Olneyi olney threesquare
Scirpus robustus saltmarsh bulrush
Fimbristylis spp. saltmarsh fimbristylis
Setaria spp. foxtail grass
Sorgum spp. grass
Zea mays corn
Acnida cannabinus (amaranthus) tidemarsh waterhemp
Polygonum spp. smartweed
Rubus spp. ' bramble
Vitis spp. grape, wild grape
Cicuta spp. water-hemlock
Potamogeton spp. pondweed 4i
undetermined vegetation 5i
Potamogeton pectinatus sago pondweed 2i
Vallisneria americana (spiralis) wiidcelery ' 11
Scirpus spp. bulrush 11
Zizania aquatica wildrice 11
Potamogeton perfoliatus redhead grass 11
Ruppia maritime > wi dgeongrass 2(
1 . . 0.0
1 . . 1.0
35 . . 18.2
67 . 1.7
33 . 3.3
33 . . 26.7
33 14 . 16.7 10.1
1 0.0
6 . . 0.1
1 0.0
1 0.0
1 . .0.0
2 . .0.6
33 27 . 33.3 16.9
33 . 0.0
33 . . 0.0
33 . 0.0
1 0.0
67 . . 0.3 . '
) 67 1 33.5 0.7 0.0
) . 1 16.6 . 0.0
) . 6 14.0 . 0.0
) 67 . 10.0 0.3
) . 1 10.0 . 0.0
) . 7.5
) . 81 4.5 . 42.9
) .45 2.0 . 6.3
Najas flexilis northern naiad 10 33 . 1.5 10.0
Total plant material 100 100 100 99.6 93.0 99.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-10. FOOD ITEMS OF AMERICAN WIGEON IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Frequency occurrence
Aggregate percent0
Common name
Gizzard Gullet
( 35) ( 4)
Unknown
( 109)
Gizzard Gullet
( 35) ( 4)
Unknown
(109)
oo
oo
Bittium varium
Planorbi dae
Gemma gemma
Macoma balthica
Nereis spp.
Amphi poda
Coelenterata (Cnidaria)
Gammarus spp.
Chi ronomi dae
Cori xi dae
Hydrophili dae
Araneae
Ulva lactuca
Enteromorpha spp.
Potamogeton perfoliatus
Zannichellia palustris
Najas guadalupensis
El odea canadensis
Cladium mariscoides
Digitaria spp.
Panicym spp.
Setaria spp.
Setaria ital.ica
Zea mays
Spartina spp.
Spartina alterniflora (stricta)
Pontederia cordata
Amaranthus spp.
Polygonum punctatum
Ruppia maritima
Characeae
Potamogeton pectinatus
Chara spp.
Zostera marina
Vallisneria americana (spiralis)
Chlorophyceae
Zizania aquatica
Distichlis spicata
Nitella spp.
Eleocharis palustris
variable bittium
orb snail
gem clam
Baltic macoma
clam worm
scud, sideswimmer
hydroid, jellyfish
scud
mi dge
water boatman
water scavenger beetle
spi der
Total animal material
sea lettuce
filamentous green algae
redhead grass
horned pondweed
southern naiad
common elodea
twi g-rush
crab grass
panic grass
foxtail grass
millet
corn
cordgrass
saltmarsh cordgrass
pickerel weed (tuckahoe)
amaranth
dotted smartweed
wi dgeongrass
muskgrass
sago pondweed
muskgrass
eelgrass
wi Idcelery
green algae
wi Idri ce
salt grass
ni tella
common spikerush
undetermined vegetation
(continued)
3
3
6
3
3
80
11
9
9
3
3
3
3
9
3
3
6
25
25
50
75
50
1
1
1
1
i
2
2
1
39
1
1
7
1
1
1
1
1
2
1
3
1
1
1
68
1
17
28
i
0. 1
0.0
0.0
2.9
66.0
6.3
6. 1
3. 1
2.9
2.9
2.8
2. 1
1.9
1.9
1.0
0.1
0.0
0.0
43.8
16.5
39.8
0. 1
0.0
0.0
0. 1
o!o
0. 1
0.3
1.0
0. 1
23. 1
0.0
0.0
5.7
0. 1
0. 1
0. 1
0.0
0.0
1. 1
0.0
1.8
0.0
0.0
0.0
39.3
o!o
9.3
13.0
o!o
-------
APPENDIX TABLE B-10. (continued)
Scientific name
Scirpus Olneyi
Sci rpus vali dus
Grami neae
Cyperus odorattes
Eleocharis parvula
Scirpus americanus
Scirpus robustus
Iva frutescens
Common name
olney threesquare
softstem bulrush
grasses
gali ngale
dwarf spikerush
common threesquare
saltmarsh bulrush
marsh-elder
Total plant material
Frequency occurrence
Gizzard Gullet Unknown
(35) ( 4) (109)
14 13
3
6 1
3
3
3
3
3
97 100 100
Aggregate
percent
Gizzard Gullet Unknown
( 35) ( 4) (109)
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
97.1 100.
1 0
0 6
0 99.7
As defined by Swanson et al. (1974).
oo
-------
APPENDIX TABLE B-11. FOOD ITEMS OF BLUE-WINGED TEAL IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Frequency occurrence
Aggregate percent'
Common name
Gizzard Gullet
( 21) ( .)
Unknown
( 34)
Gizzard Gullet
( 21) ( .)
Unknown
( 34)
VO
O
Arcuatyla demissa (Volsella)
Gammari dae
Coleoptera
Galerucella spp.
Li bellui das
Araneae
Hydrobia spp. (Littoridinops)
Podocopa
Sphenophorus spp.
Tropisternus spp.
Melampus bidentatus
Berosus spp.
Chi ronomi dae
Formi ci dae
Isopoda
Amphipoda
Scarabaei dae
Curculi oni dae
Enochrus spp.
Gastropoda
Insecta
Dytiscidae
Hydrophi1i dae
Corixi dae
Zosteraceae
Potamogeton spp.
Potamogeton pusillus
Sparganiurn americanum
Sparganiyrn eurycarpum
Eleocharis parvula
Eleocharis olivacea
Scirpus americanus
Scirpus validus
Carex crinita
Echinochloa Walteri
Zea mays
Zizania aquatica
Pontederia cordata
Chenopodium spp.
Amaranthus spp.
undetermind animal
Atlantic ribbed mussel
scud
beetle
leaf beetle
common skimmer
spider
swamp snail
ostracod
billbug
salt marsh snail
mi dge
ant
i sopod
scud, sideswimmer
scarab beetle
snout beetle
snai1, 1impet
i nsect
predaceous diving beetle
water scavenger beetle
water boatman
Total animal material
pondweed
pondweed
slender pondweed
eastern burreed
big burreed
dwarf spikerush
spi kerush
common threesquare
softstem bulrush
sedge
corn
wiIdri ce
pickerel Meed (tuckahoe)
goosefoot
amaranth
(conti nued)
24
24
29
5
10
14
5
5
5
5
5
5
5
5
5
5
5
5
67
6
3
3
3
3
3
3
38
12
15
12
59
3
3
6
12
3
9
3
6
21
3
24
3
3
6
3
3
4. 1
2.3
1.0
1.0
0.2
0.2
0.2
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
9.3
0.4
0.7
0.0
0.0
0.0
1.2
0.0
8.3
0.4
0.3
1.8
0.0
0.0
13.4
1.8
0.0
0.0
0. 1
0.0
0.0
0.0
0. 1
0.9
0.0
2. 1
2.4
0.0
0.3
0.0
0.0
-------
APPENDIX TABLE B-11. (continued)
Scientific name
Acnida cannabinus (amaranthus)
Polygonum arifolium
Polygonum hydropi peroi des
Polygonum punctatum
Ambrosia artemi si i f ol i a
Baccharis halimifolia
Scirpu's Olneyi
Ruppia maritima
Potamogeton pectinatus
Polygonum sagittatum
Scirpus robustus
Cladium mariscoides
Iva frutescens
Gramineae
Polygonum spp.
Spartina cynosuroi des'
Distichlis spicata
Sparganium androcladum
Chara spp.
Eleocharis palustris
Myrica spp.
Potamogeton perfoliatus
Cyperus odorattes
Carex spp.
Spartina spp.
Cuscuta spp.
Common name
tidemarsh waterhemp
halberdleaf teai — thumb
swamp smartweed
dotted smartweed
ragweed
groundsel tree
olney threesquare
wi dgeongrass
sago pondweed
smartweed
saltmarsh bulrush
twi g-rush
marsh-elder
grasses
smartweed
undetermined vegetation
big cordgrass
salt grass
shining burreed
muskgrass
common spikerush
wax-myrtle
redhead grass
gal i ngale
sedge
cordgrass
dodder
Total plant material
Frequency occurrence •
Gizzard Gullet Unknown
( 21) ( .) ( 34)
12
9
3
29
3
3
81 71
67 59
5
5
33 32
48 26
10 24
5 3
5
10 6
10 6
24 29
5
10 12
5 6
5 6
5 3
5
5
5
5 18
95 . ' 100
Aggregate percent
Gizzard Gullet Unknown
(21) ( .) ( 34)
0.6
0.8
0.0
19. 1
0.0
0.0
48.5 21.1
12.9 19.0
4.8
4.8
4.7 1.6
3.1 0.6
2.9 5.9
2.4 0.0
1.9
1.9 1.8
1.2 0.1
0.9 2.5
0.5
0.1 5.1
0.1 0.0
0.1 0.0
0.0 0.7
0.0
0.0
0.0
0.0 0.1
90.7 . 86.6
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-12. FOOD ITEMS OF GREEN-WINGED TEAL IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Frequency occurrence Aggregate percent
Scientific name
Amnicola spp.
Melampus bidentatus
PelGcypoda (Bivalvia)
Nerei s spp.
Isopoda
Chiridotea caeca
Lep-tochel i a savigny
Amphi poda
Gammar i das
Corophium spp.
Decapoda
Insecta
Caralsi dae
Stenolophus spp.
Triliarthrus badiipennis
Amara spp.
Phytonomus nigrirostris
Phytonomus meles
Graphops pulsescens
Hydrophi 1 i dae
Berosus spp.
Tropisternus spp.
Atheta spp.
Corixidae
Nysius spp.
Ichneumoni dae
Fulgor i dae
Di ptera
Chi ronomi dae
Tana i dae
Hydrobia spp. ( L i ttori di nops)
Bittium varium
Gastropoda
Nerei dae
Podocopa
Popillia japonica
Dyti sci dae
Sphenophorus spp.
Chara spp.
Potamogeton pectinatus
Potamogeton pusillus
Gizzard Gullet Unknown Gizzard
Common name (10) ( .) (34) (10)
amnicola . 3
salt marsh snail
bi valve
clam Norm
i sopod
i sopod
scud, sideswimmer
scud
amphipod
crayfish* shrimp
i nsect
lesser clover leaf weevil
water scavenger beetle
water boatman
i chneumoni d
fulgorid planthopper
fly
midge
15
3
9
6
6
9
9
12
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
9
9
aquatic sowbug 20 . . 9.5
swamp snail 30 . 15 4.4
variable bittium 10 ' . . 1.0
snail, limpet 10 . . 0.2
clam worm 10 . 3 0.0
ostracod 10 . 26 0.0
Japanese beetle 10 . . 0.0
predaceous diving beetle 10 . . 0.0
billbug 10 .3 0.0
Total animal material 60 . 65 15.1
muskgrass • . 12
sago pondweed 9
slender pondwaed 6
Gullet Unknown
( .) ( 34)
0.3
1. 1
0. 1
0.0
0.0
4.9
2.2
0.4
0.8
0.8
0.0
0.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0,0
0.0
0.0
0.4
1.9
.
1.0
. .
. .
0.0
1. 1
.
.
0.0
15.4
5.7
0. 1
0. 0
(conti nued)
-------
APPENDIX TABLE B-12. (continued)
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 10) ( .)
Unknown
( 34)
Gizzard Gullet
( 10) ( .)
Unknown
( 34)
VO
10
Potamogeton epihydrus
Zannichellia palustris
Najas spp.
Najas guadalupensis
Najas flexi1i s
Vallisneria americana (spiralis)
Sparganium americanum
Sagittaria latifolia
Cyperus filicinus
Eleocharis palustris
Scirpus spp.
Scirpus fluviatilis
Scirpus robustus
Carex lurida
Fuirena spp.
Rhynchospora capitellata
Echinochloa spp.
Zea mays
Spartina spp.
Pontederia cordata
Atriplex patula
Acnida cannabinus (amaranthus)
Polygonum sagittatum
Myr i ophyllurn spp.
Proserpinaca palustris
Hedeoma pulegoides
Ambrosia artemisiifolia
Bidens spp.
Iva frutescens
Portulaca spp.
Mollugo vertici11iata
Juncus Roemerianus
Scirpus Olneyi
Ruppia maritima
Polygonum punctatum
Spartina alterniflora (stricta)
Carex spp.
Distichlis spicata
Fimbristylis castanea
Cladium mariscoides
Cyperus odorattes
Leersia oryzoides
ribbonleaf pondweed
horned pondweed
nai ad
southern naiad
northern naiad
wiIdcelery
eastern burreed
broa.dleaf arrowhead
gali ngale
common spikerush
bulrush
ri ver bulrush
saltmarsh bulrush
sedge
fui rena
beak-rush
corn
cordgrass
pickerel weed (tuckahoe)
spearscale
tidemarsh waterhemp
smartweed
watermiIfoi1
marsh mermaidweed
American pennyroyal
ragweed
beggai—ti ck
marsh-elder
purslane
carpet-weed
needlerush
undetermined vegetation
olney threesquare
wi dgeongrass
dotted smartweed
saltmarsh cordgrass
sedge
salt grass
saltmarsh fimbristylis
twi g-rush
gali ngale
cut grass
(conti nued)
70
60
20
10
10
20
10
50
10
10
6
6
3
6
6
3
6
3
3
3
6
9
26
3
3
3
3
6
6
6
3
3
6
3
3
3
3
3
9
3
3
3
3
71
68
29
3
6
24
35
3
35.5
8.6
6.6
6.3
6.0
5.3
4.0
3.3
3.0
2.0
0.8
0.0
0.0
0.0
0. 1
0.0
0.0
0.3
0.0
0.0
0.0
1.5
4.6
0.0
0.0
0.0
0.0
0.0
0.7
1.3
0.0
0. 1
0.0
0.0
0.0
0.3
0.0
0.0
2.6
1.0
23.9
11.0
13.0
1.0
0.0
2.0
o i
-------
APPENDIX TABLE B-12. (continued)
Frequency occurrence
Scientific name
Polygonum pensylvani cum
Cephalanthus occi den-tali s,.
Polygonum arifolium
Cuscuta spp.
Pinus Taeda
Potamogeton spp.
Eleochar i s spp.
Eleocharis parvula
Scirpus americanus
Sci rpus vali dus
Echinochloa Walteri
Panicum spp.
Myrica cerifera
Ranunculus sceleratus
Lippia lanceolata
Teucrium canadense
Galium spp.
Nymphaea odorata (Castalia)
Common name
smar tweed
'buttonbush
halberdleaf teai — thumb
dodder
loblolly pine
pondweed
spikerush
dwarf spikerush
common threesquare
softstem bulrush
panic grass
wax-myrtle
cursed crowfoot
f og-f rui t
germander (wood sage)
bedstraw, cleavers
white water lily
Total plant material
Gizzard Gullet
( 10) ( .)
20
10
10
20
10
10
20
30
10
20
10
10
10
10
10
10
10
10
100
• Unknown
( 34)
3
12
18
,
9
3
15
15
29
3
6
3
.
.
.
.
•
100
Aggregate
percent
Gizzard Gullet Unknown
( 10) ( .) ( 34)
2.0
2.0
0.2
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
84.9
0.0
1.7
0.2
.
0.0
0.0
4. 1
0.5
3.0
0.9
0.0
0.0
.
.
,
.
•
84.6
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-13.
FOOD ITEMS OF BLACK DUCKS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
,—^tj^ ^_M^^ — ^MMM — ^u — ,»M-B— ,»,»M-^— M— —a^^M^ — ^— — •••^^»— •••.•.•••• n-. • •» •MT ^ —i »t — — — — — — — —————»^» — — —•»— — ••^••••••••••••••••^
Frequency occurrence Aggregate percent3
Scientific name
Common name
Gizzard Gullet
( 55) ( 2)
Unknown
(128)
Gizzard Gullet
( 55) ( 2)
Unknown
(128)
Gastropoda
Rissoidae
Sayella chesapeakea
Goniobasis yirginica
Bittium varium
Littorina irrorata
Mytili dae
Corbicul iiidae (Cyrenidae)
Macoma mitchelli (M. phenax)
Pisidiym atlanticum
Cyrenoida floridana (Cyrenella)
Arthropoda
Cyathura carinata (polita)
Erichsonella spp.
Chiridotoa caeca
Gammaridae
Ovalipes ocellatus
Balanus spp.
Insecta
Colcoptera
Caralsi dae
Aphodius spp.
Bidessus spp.
Galerucella spp.
Hydrophilys spp.
Staphylinidae
Gelastocori dae
tlymenoptera
Gryllotalpa
Cicadellidae
Ti pulidae
Culi ci dae
Acdes sollicitans
Aedes spp.
Hydracarina (Acarina)
Coslenterata (Cnidaria)
Molgula spp.
Cyprinodon variegatus
Melampus bidentatys
Fundulus heteroclites
Arcuatula demissa (Volsella)
Belastoma spp.
snail» limpet
ri sso
snail
snail
variable bittium
marsh periwinkle
mussel
marsh clam
Mitchell's clam
fresh-water clam
i sopod
i sopod • •
i sopod
scud
lady crab
barnacle
i nsect
beetle
• •
dung beetle
leaf beetle
Mater scavenger beetle
rove beetle
toad bug
beef wasp, ant
northern mole cricket
leafhopper
crane fly
mosquito
salt marsh mosquito
mosqui to
mi te
hydroid» jellyfish
sea grape
sheepshead minnow
salt marsh snai1
Atlantic ribbed mussel
(continued)
50
***
7
9
11
7
7
11
-------
APPENDIX TABLE B-13. (continued)
Frequency occurrence
Aggregate percent'
VO
Scientific name
Hydrobia spp. (Li ttori di nops)
Chi ronomi dae
Fundulus spp.
L i bellui dae
Macoma balthica
Cyprinodontidae
Xanthidae (Pilumnidae)
Bittium alternatum (B. nigrum)
Mollusca
Gammarus spp.
Menidia spp.
Corixidae
Tropisternus spp.
Amni col i i dae (Bulimidae)
Tell i na spp.
Paneopeus spp.
Tachi stodes spp.
Aeschni dae
Hydrophi li dae
Anguilla rostrata
Odbntomyia spp.
Graphoderes spp.
Lycosidae
Amphi ppda
Hyalella spp.
Rhi thropaneopeus harrisi
Odostomia spp.
Odostomia trifida
Amni co la spp.
Pelecypoda (Bivalvia)
Brachi odontes recurvus (Mytilus)
Gemma gemma '
Nerei dae
Nereis spp.
Isopoda
Asellidae
Orch'estia spp.
Decapoda
Podocopa
Hal i pi i dae
Dyt i sci dae
Curculi oni dae
Common name
swamp snail
midge
common skimmer
Baltic macoma
top minnow
mud crab
undetermined fish
alternate bittium
mollusk
scud
si Iversi de
water boatman
swamp snail
dwarf tellin
mud crab
darner
water scavenger beetle
American eel
wolf spider
scud, sideswimmer
amphi pod
white-fingered mud crab
odostome
tripartite odostome
amni cola
bi valve
hooked mussel
gem clam
clam worm
clam worm
i sopod
aquatic sowbug
amphi pod
crayfish, shrimp
ostracod
crawling water beetle
predaceous diving beetle
snout beetle
( 55) ( 2)
11 . •
2
5
9
.2
11
7
4
5
2 -
5
2
22
13
ft
5
2
2
T •
2
2
2
2
2
2
2
2
2
2
ft
ft
2
2
5
2
2
2
2
2
5
2
T •
ft 50
(128)
8
.
4
2
13
.
1
5
2
.
1
.
6
2
1
.
2
.
.
5
.
.
.
.
7
,
,
.
1
.
1
5
5
t
5
2
.
.
2
2
,
2
3
( 55) ( 2)
1.7
1.1
1.1
0.8
0.7
0.7
0.5
0.5
0.5
0.5
0.5
0.2
0. 1
0. 1
0.
0.
0.
0.
0.
0.
0.
0.
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0 0.0
(128)
0.3
.
1.3
0.2
2.9
.
0.0
1 . ft
0.0
.
0.2
.
0.0
0.3
0.0
.
0.5
.
.
0. 1
.
.
.
.
0.2
.
.
.
0.0
.
0.0
0.8
0.1
.
0.2
0.0
.
.
0.0
0.0
. 1»
0.0
0.0
(conti nued)
-------
APPENDIX TABLE B-13. (continued)
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 55) ( 2)
Unknown Gizzard Gullet Unknown
(128) ( 55) ( 2) (128)
Sphenophorus spp.
Enochrus spp.
Berosus spp.
Formi ci dae
Anisoptera
Araneae
Poect1i i dae
Ulva lactuca
Pinus spp.
Juniperus virginiana
Potarnogeton epihydrus
Elodea canadensis
vo Scirpus americanus
-J Scirpus fluviatilis
Carex lurida
Carex crinita
Eleusine indica
Paspalum spp.
Spartjna cynosuroides
Spartina patens
Andropogon spp.
Triticum aestivum
Peltandra virginica
Pontederia cordata
Myrica spp.
Celtis spp.
Chenopodium spp.
Atriplex patula
Amaranthus spp.
Rumex spp.
Rumex cri spus
Polygonum densiflorum
Phytolacca americana
Lespedeza stipulacea
Medicago lupulina
Melilotus spp.
Rhus spp.
Rhus Copallinum
Vitis spp.
Hibiscus Moscheutos
Teucrium canadense
Trichostema spp.
bi llbug
ant
dragonfly
spi der
Total animal material
sea lettuce
pi ne
red cedar
ribbonleaf pondweed
common elodea
common threesquare
river bulrush
sedge
sedge
yard grass
grass
big cordgrass
saltmeadoM cordgrass
beard grass
wheat
arrow arum
pickerel weed (tuckahoe)
wax-myrtle
elm
goosefoot
spearscale
amaranth
dock, sorrel
sour dock
southern smartweed
pokeweed
Korean lespedeza
black medick
sweet clover
cashew
sumac
grape, wild grape
rose-mallow
germander (wood sage)
blue curls
(continued)
2
^
2
ft
2
7
2
69
50
50
5
2
2
2
68
2
1
1
1
2
2
3
1
2
2
1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
25.9
0.0
0.2
0.2
0.0
0.0
0.0
27.0
0.5
0.0
0.0
0.0
0.2
0.3
0.0
0.0
0.0
0.0
o! 1
0.3
0.0
0.7
1.0
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0. 1
0.0
0. 1
-------
APPENDIX TABLE B-13., (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent'
Gizzard Gullet
( 55) ( 2)
Unknown
( 128)
Gizzard Gullet
( 55) ( 2)
Unknown
(128)
vo
00
Nyssa spp.
Nyssa sylvatica (biflora)
Ceratophyllum demersum
Ambrosia artemisiifolia
Iva f'rutescens
Baccharis halimifolia
Nuphar aclvena
Juncus spp.
Juncus Roemerianus
Limonium spp.
Ruppia maritima
Scirpus Olneyi
Polygonum punctatum
Cladiym mariscoides
Spartina alterniflora (stricta)
Zea mays
Distichlis spicata
Zizania aquatica
Echinochloa Walteri
Enteromorpha clathrata
Sparganium androcladum
Potamogeton perfoliatus
Pan i cum spp.
Polygonum spp.
Gramineae
Zostera marina
Polygonum arifolium
Sci rpus spp.
Ilex verticillata
Cephalanthus occidental!s
Chara spp.
Potamogeton spp.
Eleocharis palustris
Scirpus robustus
Ilex decidua
Polygonum sagittatum
Zosteraceae
Polygonum Hydropiper
Polygonum pensylvanicum
Cuscuta spp.
Rubus spp.
Sci rpus vali dus
sour gum
black gum (sour gum)
hornwort
ragweed
marsh-elder
groundsel tree
yellou water lily
rush
needlerush
sea-lavender
wi dgeongrass
olney threesquare
dotted smartweed
twig-rush
saltmarsh cordgrass
undetermined, vegetation
corn
salt grass
wiIdri ce
filamentous green alga
shining burreed
redhead grass
panic grass
smartweed
grasses
eelgrass
halberdleaf teai—thumb
bulrush
black alder (winterberry)
buttonbush
muskgrass
pondweed
common spikerush
saltmarsh bulrush
holly
smartweed
pondweed
smartweed
smartweed
dodder
bramble
softstem bulrush
(continued)
58
51
25
51
16
11
5
13
5
11
4
5
2
2
4
4
2
5
5
4
5
4
2
2
33
2
4
2
2
5
5
4
4
50
50
50
50
1
2
1
2
13
2
1
1
2
1
69
48
1 1
20
.5
6
16
19
•
4
1
20
2
1
2
11
6
2
i
1
2
1
27
1
13
4
10
20.7
9.6
6.4
4.9
4.7
4.3
3.7
2.9
2.7
2.4
2.3
0
0
0,
0,
0.4
0.4
0.4
0.4
0.4
0,
0,
0.
0,
0.
0.
0.
0.
0.
0.
.7
.7
.5
.5
.3
.3
.3
.2
46
50
0.0
0. 1
0.4
0.0
2.9
0.2
0.0
0.0
0. 1
0.6
21.7
7.0
3.9
1.7
1.2
1.3
10.8
2.5
o!o
0.6
6.*0
0.0
0.0
0.0
3.3
1.0
0.0
o.'o
0.7
0.0
0.0
1. 1
0.0
oio
0. 1
0.0
0.3
-------
APPENDIX TABLE B-13. (continued)
Frequency occurrence
Aggregate percent'
lO
10
Scientific name
Myrica cerifera
Carex spp.
Magnolia virginiana
Sparganium americanum
Cyperus spp.
Smilax spp.
Rhus glabra
Gerardia maritima
Enteromorpha spp.
Pinus Taeda
Potamogeton pectinatus
Potamogeton pusillus
Zannichellia palustris
Sparganium spp.
Eleocharis spp.
Eleocharis quadrangulata
Scirpus pallidus
Fimbristylis castanea
Leersia oryzoides
Setaria italica
Spartina spp.
Carpinus caroliniana
Salicornia Bigelovii (musronata)
Acnida cannabinus (amaranthus)
Proserpinaca palustris
Cornus spp.
Common name
wax-myrtle
sedge
sweet bay (swamp bay)
eastern burreed
gal i ngale
lily
smooth sumac
seaside gerardia
filamentous green algae
loblolly pine
sago pondweed
slender pondweed
horned pondweed
burreed
spi kerush
squarestem spi kerush
black bulrush
saltmarsh fimbristylis
cut grass
millet
cordgrass
hornbeam (blue beech)
glasswort (samphire)
tidemarsh waterhemp
marsh mermaidweed
dogwood
Total plant material
Gizzard Gullet
( 55) ( 2)
20
2
2
ft
2
2
2
2
ft
5
5
ft
. 2
2
ft
ft
2
2
ft
2
2
2
2
2
2
2
96 100
•Unknown Gizzard Gullet
(128) ( 55) ( 2)
^
,
7
.
2
.
.
.
.
11
.
1
1
1
.
.
1
1
.
5
,
.
3
.
•
99
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
74
. 1
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.1 100.0
Unknown
(128)
0
0
1
0
0
0
0
0
0
0
73
.
.
.3
.
.0
.
.
.•
.
.3
.
.0
.0
.0
.
.
.0
.0
,
.3
.
.
.0
.
•
.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-14. FOOD ITEMS OF GADWALLS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
o
o
Scientific name
Berosus spp.
Gemma gemma
Rhodophyceae
Chlorophyceae
Zostera marina
Potamogeton perfoliatus
Najas spp.
Elodea canadensi s
Scirpus americanus
Scirpus robustus
Scirpus validus
Grami neae
Spartina spp.
Acnida cannabinus (amaranthus)
Myriophyllum spp.
Ruppia maritima
Chara spp.
Potamogeton pusillus
Distichlis spicata
Scirpus Olneyi
Potamogeton spp.
Cladium mariscoides
Myrica cerifera
Common name
undetermined fish
gem clam
Total animal material
red algae
green algae
eelgrass
redhead grass
nai ad
common elodea
common threesquare
saltmarsh bulrush
softstem bulrush
grasses
cordgrass
tidemarsh watarhemp
watermi Ifoi 1
wi dgeongrass
muskgrass
slender pondweed
salt grass
olney threcsquare
pondweed
twi g-rush
wax-myrtle
Total plant material
Frequency occurrence
Aggregate percent
Gizzard Gullet Unknown Gizzard
(7) ( .) ( 21) ( 7)
5
5
14
14 . 10
5
5
14
10
19
5
5
5
5
• . . 10
10
5
5
86 . 67
14 . 10
14 . 5
14
29 .
14
14 .
14
100 . 100
0
0
56
14
12
12
2
1
0
0
100
f
.0
.0
.
.
.
.
.
f
.
.
.
.
.
.
.
.6
. 1
.9
.9
. 1
.4
.0
.0
.0
Gullet Unknown
( .) ( 21)
0.0
1.0
•
1.0
1.9
4.0
8.4
4.8
17.1
1.0
0.0
0.0
0.0
1.9
7.6
0.0
4.8
41.8
2.9
2.9
.
. •
. .
.
•
99.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-15. FOOD ITEMS OF MALLARDS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Scientific name
Bittium varium
Hydrobia spp. (L i ttori di nops)
Macoma balthica
Chiridotea caeca
Decapoda
Insecta
Sphenophorus spp.
Urochordata (Tunicata)
Arcuatula demissa (Volsella)
Arthropoda
Gammarus spp.
Melampus bidentatus
Pelecypoda (Bivalvia)
Mollusca
Gastropoda
Myt i 1 i dae
Nerei dae
Coleoptera
Formi ci dae
Lasius spp.
Araneae
Zostera marina
Vallisneria americana (spiralis)
Sparganiurn eurycarpum
Cyperus spp.
Eleochar i s spp.
Eleocharis palustris
Scirpus fluviatilis
Echinochloa Walteri
Spartina spp.
Spartina alterniflora (stricta)
Triticum aestivum
Peltandra virginica
Pontederia cordata
Amaranthus spp.
Acnida cannabinus (amaranthus)
Phytolacca americana
Agrostemma Githago
Rosa spp.
Rhus spp.
Common name
variable bittium
swamp snail
Baltic macoma
i sopod
crayfish, shrimp
insect
bi llbug
undetermined fish
Atlantic ribbed mussel
scud
salt marsh snai 1
bi valve
mollusk
snai 1 , limpet
mussel
clam worm
beetle
ant
field ant
spi der
Total animal material
eelgrass
wi Idcelery •
big burreed
gali ngale
spi kerush
common spi kerush
river bulrush
cordgrass
saltmarsh cordgrass
wheat
arrow arum
pickerel weed (tuckahoe)
amaranth
tidemarsh waterhemp
pokeweed
corn-cockle
rose
cashew
(continued)
Frequency occu
Gi zzard Gullet
( 25) ( 2)
* *
.
B ,
50
f f
, .
^ t
* *
4 50
4
4
4
8
4
4
4
4
4
.4
4
* .
24 50
.
. .
. .
• •
. .
• . •
. •
t ,
. ,
, .
, .
, ,
. ^
'
1 * • •
.
.
.
. .
rrence
Unknown
2
5
2
2
2
10
2
2
2
5
.
,
2
.
,
2
.
<
.
.
,
•
32
2
2
7
2
2
5
5
10
7
5
2
7
5
2
2
2
2
7
2
Aggregate pe
Gizzard Gullet
( 25) ( 2)
. .
9 f
. ,
10.0
. ,
. ,
. „
. .
0.4 17.5
0.2
0.2
0.2
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.1 27.5
^ ,
.
.
. .
.
.
. .
, ,
. .
.
. .
.
.
.
. .
.
.
.
.
rcent
Unknown
( 41)
0.0
0.0
0. 1
0.5
0.0
0.0
0.0
1.2
2.4
2.4
.
.
0.0
.
.
0.0
.
.
.
.
.
•
6.9
2.2
0. 1
1.8
0.0
0.0
0.0
0.0
0.4
2.7
2.2
2.0
2.0
0.0
0.0
0.0
0.0
0 . 1
0 . 1
0 . 0
-------
APPENDIX TABLE B-15. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent1
Gizzard Gullet Unknown
( 25) ( 2) ( 41)
Gizzard Gullet
( 25) ( 2)
Unknown
( 41)
o
to
Rhus radicans
Ilex spp.
Vi t i s spp.
Nyssa sylvatica (biflpra)
Ambrosia artemisiifolia
Brasenia Schreberi
Zea mays
Ruppia maritima
Scirpus spp.
Gramineae
Polygonum arifolium
Polygonum spp.
Polygonum Hydropiper
Cladium tnariscoides
Polygonum sagittatum
Cyperaceae
Distichlis spicata
Panicum spp.
Zizania aquatica
Carex spp.
Sparganium americanum
Carex lurida
Potamogeton spp..
Sparganium spp.
Scirpus Olneyi
Zosteraceae
Potamogeton pusillus
Scirpus validus
Potamogeton perfoliatus
Zannichellia palustris
Iva frutescens
Cephalanthus occidentalis
Sparganium androcladum
Scirpus americanus
Polygonum hydropiperoides
Polygonum pensylvanicum
Ilex verticillata
Cuscuta spp.
Spartina cynosuroides
Smilax spp.
Myrica cerifera
Ilex decidua
poison ivy - poison oak
holly
grape, Mild grape
black gum (sour gum)
ragweed
watershi eld
corn
widgeongrass
bulrush
grasses
halberdleaf teai—thumb
smartweed
smartweed
twi g-rush
smartweed
undetermined vegetation
sedge
salt grass
pani c 'grass
wi Idri ce
sedge
eastern burreed
sedge
pondweed
burreed
olney threesquare
pondweed
slender pondweed
softstem bulrush
redhead grass
horned pondweed
marsh-elder
buttonbush
shining burreod
common threesquare
swamp smartweed
smartweed
black alder (winterberry)
dodder
biq cordgrass
lily
wax-myrtle
holly
(continued)
16
32
32
16
12
24
8
20
20
20
4
4
4
4
8
8
4
12
8
16
4
4
8
4
4
4
8
8
8
4
4
4
8
4
4
4
4
50
50
50
50
50
50
2
5
7
5
2
2
20
37
5
17
20
5
7
15
41
34
15
24
5
12
2
14.5
14.4
11.6
6.7
5.6
4.9
4.7
4.4
4.0
3.3
3.0
3.0
2.4
2.4
2.2
1.7
1.6
0.8
0.6
0.6
0.6
0.4
0.4
0.4
0,
0,
0,
0
0
0.2
0.2
0. 1
0. 1
0. 1
17.5
5.0
1.5
5.0
1.0
2.5
0.0
0. 1
1.6
0.5
0.0
0.0
16.8
16.2
2.9
1.8
2.1
os
2.4
4. 1
2.8
oo
1.2
0. 1
-------
APPENDIX TABLE B-15. (continued)
o
CO
Scientific name
Hibiscus Moscheutos
Polygonum punctatum
Chara spp.
Pinus Taeda
Juniperus virginiana
Potamogeton pectinatus
Scirpus robustus
Leersia oryzoides
Rhus glabra
Proserpinaca palustris
Pinus spp.
Eleocharis quadrangulata
Paspalum spp.
Andropogon spp.
Myrica spp.
Rumex spp.
Rosa palustris
Juncus spp.
Common name
rose-mallow
dotted smartweed
muskgrass
loblolly pine
red cedar
sago pondweed
saltmarsh bulrush
cut grass
smooth sumac
marsh mermaidweed
pine
squares-tern spikerush
grass
beard grass
wax-myrtle
dock, sorrel
swamp rose
rush
Total plant material
Frequency occu
Gi zzard Gullet
( 25) ( 2)
4
12 50
4 50
4
8
4 50
4
4
4
4
4
4
4
8
4
4
4
*
100 100
rrence
. Unknown
( 41)
29
5
.
.
2
22
.
.
.
.
.
.
.
12
5
.
•
95
Aggr
Gi zzard
( 25)
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
98.9
egate percent
I Gullet Unknown
( 2) ( 41)
* •
12.5 5.8
25.0 0.9
.
, .
2.5 2.0
2.7
.
, .
. .
.
.
. .
.
1.2
1.2
.
•
72.5 93.1
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE B-16,
FOOD ITEMS OF PINTAILS IN CHESAPEAKE BAY DURING THE PERIOD 1890 - 1959
Frequency occurrence
Scientific name
Aggregate percent0
Common name
Gizzard Gullet
( 13) ( .)
Unknown
( 36)
Gizzard Gullet
( 13) ( .)
Unknown
( 36)
o
.e-
Sayella chesapeakea
Pleuroceridae
Goniobasis virginica
Triphora nigrocincta (Tr.iforis)
Retysa canaliculata (Acteocina)
Amnicola spp.
Myti1i dae
Modiolus spp. (Volsella)
Gemma gemma
Macoma mitchelli (M. phenax)
Nerei dae
Nerei s spp.
Cyathura carinata (polita)
Erichsonella spp.
Amphipoda
Insecta
Coleoptera
Curculi oni dae
Pentatomi dae
Hymenoptera
Lepi doptera
Ani soptera
Decapoda
Melainpus bidentatus
Molgula manhattensis
Arcuatula demissa (Volsella)
Nassarius vibex
Bi tti ym vari um
Anachis avara
Mytilus eduli s
Bittium alternatum (B. nigrum)
Nassarius obsoletus (Nyanassa)
Gastropoda
Nassarius spp.
Dyti sci dae
Potamogeton spp.
Potamogeton perfoliatus
Zannichellia palustris
Elodea canadensis
Sparganiym americanum
Eleocharis obtusa
snai 1
river snail
snai 1
black triphora
channeled barrel bubble
amni cola
mussel
mussel
gem clam
Mitchell's clam
clam worm
clam worm
i sopod
i sopod
scud, sideswimmer
insect
beetle
snout beetle
stink bug
bee, wasp, ant
butterfly, moth
dragonfly
crayfish, shrimp
salt marsh snail
sea grape
Atlantic -ribbed mussel
mottled dog whelk
variable bittium
greedy dove shell
blue mussel
alternate bittium
mud dog whelk
snail, limpet
dog whelk
predaceous diving beetle
Total animal material
pondweed
redhead grass
horned pondwecd
common elodea
eastern burreed
blunt spikerush
(continued)
8
8
8
8
15
8
8
8
8
15
8
8
8
54
3
3
3
3
3
3
3
3
6
3
6
3
3
3
3
3
3
3
3
3
3
3
6
6
3
22
6
8
3
3
8
3
6.0
4.6
3.8
0.8
0.4
0.3
0.3
0.3
0.2
0.2
0.0
0.0
0.0
16.8
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0. 1
o!o
o.'o
0.0
2.5
0.0
0.7
0.0
1.4
0.6
0.0
-------
APPENDIX TABLE B-16. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent1
Gizzard Gullet Unknown Gizzard Gullet Unknown
(13) ( .) ( 36) ( 13) ( .) ( 36)
Scirpus Olneyi
Scirpus robystus
Sci rpus vali dus
Carex spp.
Digitaria sanguinalis
Echinochloa crusgalli
Panicum spp.
Paspalum spp.
Setaria spp.
Setaria italica
Spartina cynosuroides
Distichlis spicata
Chenopodium spp.
Amaranthus spp.
Polygpnum arifolium
Polygonum lapathifolium
Polygonum pensylvanicum
Polygonum Persicaria
Polygonum punctatum
Polygonum coccineum
Rubus spp.
Rhus Copallinum
Cuscuta spp.
Cephalanthus occidental!s
Nyssa sylvatica (biflora)
Ambrosia spp.
Zea mays
Potamogeton pectinatus
Ruppia maritima
Scirpus americanus
Echinochloa spp.
Spartina alterniflora (stricta)
Panicum dichotomiflorum
Cladium mariscoides
Digitaria spp.
Myrica spp.
Zostera marina
Eleocharis spp.
Eleocharis quadrangulata
Scirpus spp.
Grami neae
Myrica carolinensis
Myrica cerifera
olney threesquare
saltmarsh bulrush
softstem bulrush
sedge
crab grass
barnyard grass
panic grass
grass
foxtai1 grass
mi list
big cordgrass
salt grass
goosefoot
amaranth
halberdleaf teai—thumb
nodding smartweed
smartweed
smartweed
dotted smartweed
marsh smartweed
bramble
sumac
dodder
buttonbush
black gum (sour gum)
ragweed
corn
sago pondweed
wi dgeongrass
common threesquare
saltmarsh cordgrass
panic grass
twi g-rush
crab grass
wax-myrtle
eelgrass
spi kerush
squarestem spikerush
bulrush
grasses
wax-myrtle
wax-myrtle
(conti nued)
54
15
54
8
8
8
8
15
8
8
15
8
8
8
8
8
8
11
6
1 1
3
3
3
11
3
1 1
6
3
6
3
8
6
6
14
11
8
3
3
3
3
6
6
3
58
17
17
8
17
14
3
3
8
3
53.6
11.4
6.3
3.8
3. 1
2.7
0.8
0.5
0.4
0.4
0.2
0.0
0.0
0.0
0.0
0.0
0.0
2.9
0.0
1.0
0.0
0.0
0.0
0.5
0.0
0.6
3.7
0. 1
0.4
0.0
0.0
0.4
0.4
3.6
2.8
6.3
0.4
0.0
0.0
0.0
2. 1
0.3
0.0
48. 1
0.5
0.8
0.9
4.3
0.0
0.8
0.0
0.0
-------
APPENDIX TABLE B-16. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent'
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 13) ( .) ( 36) ( 13) ( .) ( 36)
Bidens spp.
beggai—ti ck
Total plant material
8
100
100
0.0
83.2
97.5
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-1,
FOOD ITEMS OF CANADA GEESE IN CHESAPEAKE BAY DURING THE PERIOD I960 - 1969
Frequency occurrence
Scientific name
Common name
Aggregate percent
Gizzard Gullet
(221) ( .)
Unknown Gizzard Gullet Unknown
( .) (221) ( .) ( .)
Gramineae
Zea mays
Myriophyllum spicatum
Trifolium repens
Digitaria sanguinalis
Potamogeton perfoliatus
Triticum aestivum
Najas gyadalupensis
Digitaria filiformis
Cyperus esculentus
Nyssa sylvatica (biflora)
Ruppia maritima
Ulva lactuca
Spartina patens
Glycine Max
Panicym dichotomiflorum
Spartina cynosuroides
Hordeym vulgare
Setaria geniculata
Cladium mariscoides
Polygonum pensylvanicum
Ceratophyllum demersum
Scirpus validus
Zostera marina
Setari a Faberi i
Ipomoea hederacea
Avena sati va
Echinochloa crusgalli
Bi dens laevi s
Polygonum lapathifolium
Polygonum Persicaria
Albizia Julibrissin
Prunus serotina
Solanym carolinense
Leersia oryzoides
Setaria viridis
Myrica cerifera
Cornus florida
Nyssa biflora
Ambrosia artemisiifolia
Datura stramonium
Eleusine indi ca
grasses
corn
Eurasian watermilfoil
white clover
crab grass
redhead grass
wheat
southern naiad
crab grass
gali ngale
black gum (sour gum)
wi dgeongrass
sea lettuce
saltmeadow cordgrass
soy bean
panic grass
big cordgrass
barley
foxtai1 grass
twig-rush
smartweed
hornwort
softstem bulrush
eelgrass
foxtail grass
morning glory
oats
barnyard grass
beggai—ti ck
nodding smartweed
smartweed
acacia (silk-tree)
wild cherry (black cherry)
horse-nettle
cut grass
foxtail grass
wax-myrtle
flowering dogwood
water gum
ragweed
j imson-weed
yard grass
(conti nued)
36
36
10
7
9
5
4
3
3
3
1
2
0
3
2
0
1
0
0
1
0
0
0
0
0
0
0
0
1
0
0
32.4
29.6
7.0
5. 1
3.0
2.7
2.6
2. 1
1.5
1.5
1.3
1.2
0.9
0.9
0.8
0.8
0.8
0.8
0.6
0.6
0.6
0.5
0.4
0.3
0.3
0.3
0.2
0.2
0.2
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
-------
o
00
APPENDIX TABLE C-1.« (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet Unknown Gizzard Gullet Unknown
(221) ( .) ( .) (221) ( .) ( .)
Polygonum punctatum
Rhus radicans
Vi ti s aesti vali s
dotted smartweed
poison ivy - poison oak
summei—grape
Total plant material
0.0
0.0
0.0
100.0
Unpublished data from Rawls (in prep.).
b
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-2. FOOD ITEMS OF BUFFLEHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969'
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 27) ( .)
Unknown
( .)
Gizzard Gullet
(27) ( .)
Unknown
( .)
Balanus spp.
Rhithropaneopeus harrisi
Mya arenaria
Isopoda
Pelecypoda (Bivalvia)
Macoma balthica
Macoma mitchelli (M. phenax)
Congeria leucophaeta
Mulinia lateralis
Odostomia impressa
Anneli da
Gammarus spp.
Arcuatula demissa (Volsella)
Retusa canaliculata (Acteocina)
Amphi poda
Brachiodontes recurvus (Mytilus)
Hydrobi i dae
Edotea triloba
Gastropoda
Sayella chesapeakea
Insecta
Membranipora spp.
Ruppia maritima
Potainogeton perfoliatus
Najas guadalupensis
Scirpus validus
Potamogeton pusillus
Zannichellia palustris
Nyssa sylvatica (biflora)
Myriophyllum spicatum
Cladium mariscoides
barnacle
undetermined fish
white-fingered mud crab
soft-shelled clam
i sopod
bi valve
Baltic macoma
Mitchell's clam
Conrad's false mussel
duck clam
incised odostome
leech, polychaete
scud
Atlantic ribbed mussel
channeled barrel bubble
scud, sideswimmer
hooked mussel
i sopod
snai1» limpet
snai 1
insect
bryozoan
Total animal material
wi dgeongrass
redhead grass
southern naiad
softstem bulrush
slender pondweed
horned pondweed
black gum (sour gum)
Eurasian watermilfoil
twig-rush
Total plant material
22
11
22
26
15
7
7
19
15
15
1 1
15
7
56
52
11
10.0
8.5
7.2
7.0
5.9
4.8
3.8
2.6
2.0
1.5
1.5
1.3
0.9
0.6
0.4
0.2
0.2
0.0
0.0
0.0
0.0
68.0
13.5
11.8
0.4
0.4
0.4
0.2
0.0
32.6
Unpublished data from Rawls (in prep.).
b i
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-3. FOOD ITEMS OF COMMON GOLDENEYES IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969'
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 45) ( .)
Unknown
( .)
Gizzard Gullet
( 45) ( .)
Unknown
( .)
Rhithropaneopeus harrisi
Mya arenaria
Balanus spp.
Pelecypoda (Bivalvia)
Congcria leucophaeta
Arcuatula demissa (Volsella)
Ma coma mitchelli (M. phenax)
Cyathura polita
Amphi poda
Gastropoda
Paneopeus spp.
Macoma balthica
Membranipora spp.
Odostomia impressa
Eurypanopeus depressus
Brachiodontes recurvus (Mytilus)
Zea mays
Ruppia maritima
Ceratophyllum demersum
Scirpus robustus
Potamogeton perfoliatus
Scirpus validus
Myriophyllum spicatum
Ulva lactuca
Robinia Psuedoacacia
Najas guadalupensis
Vallisneria americana (spiralis)
Nyssa biflora
Potamogeton pusillus
Vi ti s spp.
Potamogeton pectinatus
Grami neae
white-fingered mud crab
.soft-shelled clam
barnacle
bivalve
Conrad's false mussel
Atlantic ribbed mussel
Mitchell's clam
isopod
scud, sideswimmer
snai1, 1impet
mud crab
Baltic macoma
bryozoan
incised odostorne
mud crab
hooked mussel
Total animal material
corn
Mi dgeongrass
hornwort
saltmarsh bulrush
redhead grass
softstem bulrush
Eurasian watermiIfoi1
sea lettuce
black locust
southern naiad
wiIdcelery
water gum
slender pondweed
grape, wild grape
sago pondweed
grasses
Total plant material
33
33
20
27
2
13
7
4
2
2
4
2
2
4
7
2
31
33
4
2
7
2
2
2
2
2
2
2
2
2
2
4
19.4
14.9
9.2
9.0
2.1
1.4
1. 1
1.0
1.0
0.9
0.8
0.4
0.3
0. 1
63. 1
17.7
7.3
3.9
2.2
1. 1
1. 1
1. 1
0.6
0.4
0,
0,
0.
0,
0,
.3
,3
.3
,2
.2
0.0
0.0
36.9
a
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-4. FOOD ITEMS OF CANVASBACKS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969'
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
(246) ( .)
Unknown Gizzard Gullet Unknown
( .) (246) ( .) ( .)
Macoma balthica
Mya arenaria
Congeria leucophaeta
Eurypanopeus depressus
Rhithropaneopeus harrisi
Balanus spp.
Ranqia cyneata
Macoma mitchelli (M. phenax)
Brachiodontes recurvus (Mytilus)
Gastropoda
Mulinia lateralis
Cyathura polita
Amygdulum papyria (Volsella)
Gemma gemma
Hydrozoa
Retusa canaliculata (Acteocina)
Atnphi poda
Hydrobi i dae
Pelecypoda (Bivalvia)
Odonata
Sayella chesapeakea
Triphora nigrocincta (Triforis)
Arcuatula demissa (Volsella)
Crustacea
Microciona prolifera
Pogoni as cromi s
Zea mays
Potamogeton perfoliatus
Ruppia maritima
Myriophyllum spicatum.
Ulva lactuca
Najas guadalupensis
Triticum aestivum
Chlorophyceae
Nyssa sylvatica (biflora)
Spartina cynosuroides
Rhus radicans
Myrica cerifera
Vitis spp.
Baltic macoma
soft-shelled clam
Conrad's false mussel
mud crab
white-fingered mud crab
barnacle
brackish water clam
Mitchell's clam
hooked mussel
undetermined fish
snai1, 1impet
duck clam
i sopod
paper mussel
gem clam
hydroid
channeled barrel bubble
scud, sideswimmer
bi valve
dragonfly, damselfly
snai 1
black triphora
Atlantic ribbed mussel
crustacean
red sponge
black drum
Total animal material
corn
redhead grass
widgeongrass
Eurasian watermilfoil
sea lettuce
southern naiad
wheat
green algae
black gum (sour gum) •
big cordgrass
poison ivy - poison oak
wax-myrtle
grape, wiId grape
(continued)
26
33
8
5
9
5
3
2
3
3
9
2
1
1
2
1
2
1
2
0
1
1
1
1
0
1
1
33
42
34
16
4
5
2
1
4
2
0
2
3
19.6
16.3
2.7
1.7
1.5
1.2
1. 1
0.9
0.6
0,
0.
0,
0,
0,
0,
0.
0,
0,
0,
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
47.8
18.4
14.3
7.4
3.3
1.8
1.7
1.5
0.6
0.5
0.4
0.4
0.3
0.2
-------
APPENDIX TABLE C-4. (continued)
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown
(246) ( .) ( .)
Gizzard Gullet
(246) ( .)
Unknown
( .)
Is)
Potamogeton pectinatus
Cladium mariscoides
Smilax spp.
Spartina alterniflora (stricta)
Iva frutescens
Nyssa biflora
Myrica pensylvanica
Prunus serotina
Polygonum punctatum
Enteromorpha spp.
Sparganium americanum
Sparganium eurycarpum
Scirpus validus
Liquidambar styraciflua
Zostera marina
Scirpus americanus
Scirpus robustus
Echinochloa Walteri
Polygonum pensylvanicum
Polygonum Persicaria
Rubus spp.
Cuscuta spp.
Ipomoea hederacea
sago pondweed
twi g-rush
lily
saltmarsh cordgrass
marsh-elder
water gum
bayberry
wild cherry (black cherry)
dotted smartweed
filamentous green algae
eastern burreed
big burreed
softstem bulrush
sweet gum (red gum)
eelgrass
common threesquare
saltmarsh bulrush
smartweed
smartweed
bramble
dodder
morning glory
Total plant material
1
2
0
1
0
0.2
0.2
0.2
0
0
0
0
0
0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
52.3
b
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-5. FOOD ITEMS OF GREATER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969C
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet
(9) ( .)
Unknown
( .)
Gizzard Gullet
(9) ( .)
Unknown
( .)
Brachiodontes recurvus (Mytilus)
Pelecypoda (Bivalvia)
Congeria leucophaeta
Mylinia lateralis
Littorina irrorata
Arcuatula demissa (Volsella)
Rhithropaneopeus harrisi
Hydrobi i dae
Eurypanopeus depressus
Potamogeton perfoliatus
Potamogeton pusillus
Ruppia maritima
Hordeum vulgare
Scirpus americanus
Zea mays
Nyssa sylvatica (biflora)
Cladium mariscoides
Spartina cynosuroides
Myriophyllum spicatum
Cornus Amoinum
hooked mussel
bi valve
Conrad's false mussel
duck clam
marsh periwinkle
Atlantic ribbed mussel
white-fingered mud crab
mud crab .
Total animal material
redhead grass
slender pondweed
widgeongrass
barley
common threesquare
corn
black gum (sour gum)
twig-rush
big cordgrass
Eurasian watermiIfoi1
dogwood
undetermined vegetation
Total plant material
56
33
33
22
11
22
11
22
11
33
11
33
48.3
6.7
2.2
2.2
1. 1
1. 1
1. 1
0.0
0.0
62.8
10.0
4.4
3.9
1. 1
1. 1
0.6
0.6
0.6
0.6
0.6
37.2
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-6. FOOD ITEMS OF LESSER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969a
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet
( 82) ( .)
Unknown
( .)
Gizzard Gullet
( 82) ( .)
Unknown
( .)
Mya arenaria
Brachiodontes recurvus (Mytilus)
Balanus spp.
Congeria leucophaeta
Odostomia impressa
Macoma balthica
Rhithropaneopeus harrisi
Mulinia lateralis
Hydrobi i dae
Gemma gemma
Arcuatula demissa (Volsella)
Amygdulum papyria (Volsella)
Amphipoda
Gastropoda
Isppoda
Epitonium rupicola
Pyramidellidae (Turbinellidae)
Crustacea
Palaemonetes spp.
Retusa canaliculata (Acteocina)
Cyathura polita
Odonata
Araneae
Melampus bidentatus
Laevicardium mortoni
Ruppia maritima
Zea mays
Potamogeton perfoliatus
Najas guadalupensis
Myriophyllum spicatum
Sci rpus vali dus
Iva frutescens
Ulva lactuca
Potamogeton pectinatus
Polygonufn pensylvani cum
Scirpus americanus
Nyssa biflora
Eleocharis obtusa
Heteranthera dubia
soft-shelled clam
hooked mussel
barnacle
Conrad's false mussel
incised odostome
Baltic macoma
white-fingered mud crab
duck clam
gem clam
undetermined fish
Atlantic ribbed mussel
paper mussel
scud, sideswimmer
snai1» limpet
i sopod
lined wentletrap
pyramid shell
crustacean
grass shrimp
channeled barrel bubble
i sopod
dragonfly, damselfly
spider
salt marsh snai1
Morton's cockle
Total animal material
widgeongrass
corn
redhead grass
southern naiad
Eurasian Hater-milfoil
softstem bulrush
marsh-elder
sea lettuce
sago pondweed
smartweed
common threesquare
water gum
blunt spikeru:>h
water stai—grass
(continued)
28
24
18
18
27
6
6
10
15
4
1
7
5
2
66
29
46
5
7
9
4
5
7
5
1
1
12.3
6.9
5.2
5.0
3.5
2.7
2.4
2.2
1.8
6
0.5
: 0.4
0.4
0
0
0
0
0
0
0
0
0.0
•0.0
47.6
20.5
11.6
10.8
2.6
2. 1
1.3
1.2
1.0
0.9
0.7
0.5
0.4
0.4
0.4
-------
APPENDIX TABLE C-6. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 82) (.)(.) ( 82) ( .) ( .)
Digitaria filiformis crab grass
Sparganium americanum eastern burreed
Potamogeton pusillus slender pondweed i
Rhus radicans poison ivy - poison oak 1
Cuscuta spp. dodder '<.
Scirpus Olneyi olney threesquare
Myrica pensylvanica bayberry <
Liquidambar styraciflua sweet gum (red gum) '<.
Prunus serotina wild cherry (black cherry)
Nyssa sylvatica (biflora) black gum (sour gum)
Cladium jamaicense sawgrass
Hordeum vulgare barley
Learsia oryzoides cut grass
Smi lax spp. 1 i ly
Myrica cerifera wax-myrtle i
Rubus spp. bramble '<.
Rhus glabra smooth sumac
Ilex opaca American holly
Cornus Amomum dogwood
Cornus florida flowering dogwood
Gracilaria spp. red weed i
Chlorophyceae green algae
Spartina alterniflora (stricta) saltmarsh cordgrass
Total plant material
1
1
•>
,
t
\
>
i
•
o.:
o.:
o.:
0.;
o.:
0.
0.
0.
"o.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
o.t
o.c
o.t
56. 1
J
1
.
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-7. FOOD ITEMS OF RING-NECKED DUCKS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969'
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet
( 10) ( .)
Unknown
( .)
Gizzard Gullet
( 10) ( .)
Unknown
( .)
Brachiodontes recurvus (Mytilus)
Mya arenaria
Odostomia impressa
hooked mussel
soft-shelled clam
incised odostome
Total animal material
10
10
10
unpublished data from Rawls (in prep.).
3.0
3.0
0.0
6.0
Potamogeton perfoliatus
Ruppi a mari tima
Prunus serotina
Zea mays
Quercus spp.
Cladium mariscoides
Ulva lactuca
Myriophyllum spicatum
Scirpus validus
Potamogeton pectinatus
Sparganium americanum
Cornus florida
Ipomoea hederacea
Cladium jamaicense
Myrica pensylvanica
Polygonum punctatum
redhead grass
widgeongrass
wild cherry (black cherry)
corn
oak
twi g-rush
sea lettuce
Eurasian watermilfoil
softstem bulrush
sago pondweed
eastern burreed
flowering dogwood
morning glory
sawgrass
bayberry
dotted smartweed
Total plant material
60
40
10 •
30
10
10
10
10
10
10
10
10
10
10
10
10
..
37.0
12.0
10.0
8.0
8.0
5.5
5.0
3.0
.5
.0
.0
.0
.0
0.0
0.0
0.0
94.0
. .
.
. .
.
.
. .
. .
.
.
.
.
.
.
.
.
•
•
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-8.
FOOD ITEMS OF REDHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969
Frequency occurrence
a
Aggregate percent
Scientific name
Common name
Gizzard Gullet
( 77) ( .)
Unknown
( .)
Gizzard Gullet
( 77) ( .)
Unknown
( .)
Congeria leucophaeta
Mya arenaria
Macoma balthica
Macoma mitchelli (M. phenax)
Rangia cuneata
Balanus spp.
Pelecypoda (Bivalvia)
Arcuatula demissa (Volsella)
Brachiodontes recurvus (Mytilus)
Odostomia impressa
Rhithropaneopeus harrisi
Epiionium rupicola
Formi ci das
Microciona prolifera
Zea mays
Potamogeton perfoliatus
Ruppia maritima
Myr i ophyllutn spicatum
Triticum aestivum
Najas guadalupensis
Scirpus validus
Ulva lactuca
Enteromorpha spp.
Nyssa sylvatica (biflora)
Potamogeton amplifolius
Cladium mariscoides
Prunus serotina
Hordeum vulgare
Polygonum punctatum
Potamogeton pectinatus
Cladium jamaicense
Polygonum pensylvanicum
Rhus glabra
Iva frutescens
Conrad's false mussel
soft-shelled clam
Baltic macoma
Mitchell's clam
brackish water clam
barnacle
bi valve
Atlantic ribbed mussel
hooked mussel
incised odostome
white-fingered mud crab
lined wentletrap
ant
red sponge
Total animal material
corn
redhead grass
MIdgeongrass
Eurasian watermiIfoi1
wheat
southern naiad
softstem bulrush
sea lettuce
filamentous green algae
black gum (sour gum)
bigleaf pondweed
twi g-rush
wild cherry (black cherry)
barley
dotted smartweed
sago pondweed
sawgrass
smartweed
smooth sumac
marsh-elder
Total plant material
5
4
6
4
3
8
1
ft
5
5
4
1
1
1
36
39
35
13
6
6
3
-------
APPENDIX TABLE C-9. FOOD ITEMS OF AMERICAN WIGEON IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969
a
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
(121) ( .)
Unknown
( .)
Gizzard Gullet
(121) ( .)
Unknown
( .)
oo
Macoma balthica
Amphipoda
Mya arenaria
Rhithropaneopeus harrisi
Gastropoda
Ruppia maritima
Potamogeton perfoliatus
Myriophyllum spicatum
Najas guadalupensis
Ulva lactuca
Zea mays
Iva frutescens
Chlorophyceae
Zostera marina
Potamogeton pectinatus
Polygonunt pensylvani cum
Rhus radicans
Zizania aquatica
Rubus spp.
Rhus Copallinum
Baltic macoma
scud, si deswi rnmer
soft-shelled clam
white-fingered mud
snail, limpet
crab
Total animal material
Mi dgeongrass
redhead grass
Eurasian watermilfoil
southern naiad
sea lettuce
corn
marsh-elder
green algae
eelgrass
sago pondweed
smartweed
poison ivy - poison oak
wiIdri ce
bramble
sumac
Total plant material
3
3
1
2
2
53
40
40
10
9
7
4
2
2
2
1
1
1
1
1
1.0
0.8
0.2
0.2
0.0
2.2
31.1
23.6
23.5
5.8
4.5
3.5
3.2
1.8
0.6
0.0
0.0
0.0
0.0
0.0
0.0
97.7
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-10. FOOD ITEMS OF GREEN-WINGED TEAL IN CHESAPEAKE BAY DURING THE PERIOD I960 - 1969
Scientific name
Acnida cannabinus (amaranthus)
Polygonum Persicaria
Iva frutescens
Scirpus robustus
Zea mays
Polygonum pensylvani cum
Echinochloa Walter i
Scirpus validus
Scirpus americanus •
Eleocharis obtusa
Scirpus Olneyi
Polygonum punctatum
Echinochloa crusgalli
Myriophyllum spicatum
Common name
tidemarsh waterhemp
smartweed
marsh-elder
saltmarsh bulrush
corn
smartueed
softstem bulrush
common -fchreesquare
blunt spikerush
olney -threesquare
dotted smartweed
barnyard grass
Eurasian watermi Ifoi 1
Total plant material
Frequency occurrence Aggregate percent
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 13) (.)(.) ( 13) ( .) ( .)
85 51.9
54
31
23
8
15
23
31
38
8
15
15
8
8
12.7
12.7
4.2
4.2
4.2
3. 1
2.3
1.9
0.8
0.8
0.8
0.4
0.0
100.0
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-11
FOOD ITEMS OF BLACK DUCKS IN CHESAPEAKE BAY DURING THE PERIOD I960
Frequency occurrence
- 19693
Aggregate percent
Scientific name
Common name
Gizzard Gullet
(131) ( .)
Unknown Gizzard Gullet Unknowr
( .) (131) ( .) ( .)
N>
O
Congeria leucophaeta
Gammaridae
Mya arenaria
Macoma balthica
Pelecypoda (Bivalvia)
Cyathura polita
Balanus spp.
Brachiodontes recurvus (Mytilus)
Lepi doptera
Hydrobi i dae
Epitonium rupicola
Mulinia lateral is
Coleoptera
Melampus bidentatus
Arcuatula demissa (Volsella)
Insecta
Odonata
Pectinatella magnifica
Zea mays
Potamogeton perfoliatus
Ruppia maritima
Myriophyllum spicatum
Ulva lactuca
Najas guadalupensis
Polygonum pensylvanicum
Nyssa sylvatica (biflora)
Polygonum punctatum
Sparganium americanum
Iva frutescens
Polygonum Persicaria
Avena sativa
Cyperus es'culentus
Cladium mariscoides
Grami neae
Echinochloa crusgalli
Distichlis spicata
Polygonum densiflorum
Smi lax spp..
Amaranthus hybridus
Conrad's false mussel
scud
soft-shelled clam
Baltic macoma
bi valve
i sopod
barnacle
undetermined fish
hooked mussel
butterfly* moth
lined wentletrap
duck clam
beetle
salt marsh snail
Atlantic ribbed mussel
insect
dragonfly, damselfly
bryozoan
Total animal material
corn
redhead grass
widgeongrass
Eurasian watermiIfoi1
sea lettuce
southern naiad
smartueed
black gum (sour gum)
dotted smartucied
eastern.burreed
marsh-elder
smartweed
oats
gali ngale
twi g-rush
grasses
barnyard grass
salt grass
southern smartweed
lily
prince's feather
(conti nued)
3
5
3
3
2
2
2
27
44
40
13
9
6
12
7
6
1 1
4
14
2
4
3
3
5
2
2
5
1
1.9
1.8
0.9
0.6
0.3
0.3
0.2
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
6.4
17.5
15.5
14.2
8.4
5.8
3.8
2.8
2.7
2.6
2.2
2.0
1.8
1.4
1.3
1.0
0.9
0.8
0.8
0.8
0.7
0.7
-------
APPENDIX TABLE C-11. (continued)'
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
(131) ( .) ( .) (131) ( .) ( .)
Acnida cannabtnus (amaranthus)
Polygonum arifolium
Scirpus validus.
Pinus Taeda
Scirpus americanus
Myrica cerifera
Potamogeton amplifolius
Rhus Copallinum
Ilex lacvigata
Chlorophyceae
Panicum dichotomiflorum
Spartina cynosuroides
Prunus serotina
Ambrosia artemisiifolia
Dacodon verticillatus
Potamogeton pusillus
Zannichellia palustris
Vallisneria americana (spiralis)
Sparganium eurycarpum
Potamogeton pectinatus
Eleocharis quadrangulata
Nyrica pensylvanica
Rhus radicans
Potamogeton nodosus (americanus)
Digitaria sanguinalis
Paspalum laeve
Vitis vulpina (cordifolia)
Ipornoea hederacea
Scirpus Olneyi
Digitaria filiformis
Phytolacca americana
Liquidambar styraciflua
Rubus spp.
Rhus Toxicodendron
Ilex opaca
Berchemia scandens
Eleocharis obtusa
Scirpus robustus
Eleusine indica
Echinochloa colonum
Setari a Faberi i
Cuscuta spp.
tidemarsh waterhemp
halberdleaf tear-thumb
softstem bulrush
loblolly pine
common threesquare
wax-myrtle
bigleaf pondweed
sumac
wi nterberry
green algae
panic grass
big cordgrass
wild cherry (black cherry)
ragweed
water-wi How
slender pondweed
horned pondweed
wiIdcelery
big burreed
sago pondweed
squarestem spikerush
bayberry
poison ivy - poison oak
longleaf pondweed
crab grass
grass
forest-grape
morning glory
undetermined vegetation
olncy threesquare
crab grass
pokeweed
sweet gum (red gum)
bramble
poi son-oak
American holly
supple-jack
blunt spikerush
saltmarsh bulrush
yard grass
jungle rice
foxtail grass
dodder
(conti nued)
1
2
5
1
3
4
11
3
1
1
3
1
2
2
1
3
2
2
1
3
2
2
2
2
3
1
2
1
2
1
3
2
1
2
0.6
0.4
0.3
0.3
0.3
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
-------
APPENDIX TABLE C-11. (continued)
Frequency occurrence Aggregate percent
Scientific name
Nyssa aquatics
Solanum carplinense
Sambucus canadensis
Nymphaea odorata (Castalia)
Common name
sour gum
horse-nettle
common-elder
white water lily
Total plant material
Gizzard Gullet
(131) ( .)
1
1
1
1
•
Unknown Gizzard Gullet
( .) (131) ( .)
0.0
0.0
0.0
0.0
93.5
Unknown
•
•
Unpublished data from Rawls (in prep.).
i
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE C-12.
FOOD ITEMS OF MALLARDS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 1969
Frequency occurrence
a
Aggregate percent
b
Scientific name
Common name
Gizzard Gullet Unknown
(134) ( .) ( .)
Gizzard Gullet
(134) ( .)
Unknown
( .)
N)
U)
Congeria leucophaeta
Mya arenaria
Libelluidae
Balanus spp.
Brachiodontes recurvus (Mytilus)
Lyrogyrus spp.
Rangia cuneata
Macoma balthica
Amphipoda
Insecta
Corixi dae
Lepidoptera
Macoma mitchelli (M. phenax)
Odonata
Epitonium rupicola
Zea mays
Potamogeton perfoliatus
Ruppia maritima
Nyssa sylvatica (biflora)
Gramineae
Myriophyllum spicatum
Najas guadalupensis
Polygonum punctatum
Prunus serotina
Quercus spp.
Scirpus americanus
Polygonum pensylvanicum
Sparganium americanum
Triti.cum aestivum
Panicum dichotomiflorum
Potamogeton pusillus
Chlorophyceae
Scirpus validys
Digitaria filiformis
Poiygonum arifolium
Nyssa biflora
Myrica cerifera
Iva frutescens
Cyperus strigosus
Spartina cynosuroides
Conrad's false mussel
soft-shelled clam
common skimmer
barnacle
hooked mussel
snai 1
brackish water clam
Baltic macoma
scud, sideswimmer
i nsect
water boatman
butterfly, moth
Mitchell's clam
dragonfly, damselfly
li ned wentletrap
Total animal material
corn
redhead grass
widgeongrass
black gum (sour gum)
grasses
Eurasian watermiIfoi1
southern naiad
dotted smartweed
wild cherry (black cherry)
oak
common threesquare
smartweed
eastern burreed
wheat
panic grass
slender pondweed
green algae
softstem bulrush
crab grass
halberdleaf teai—thumb
water gum
wax-myrtle
marsh-elder
galingale
big cordgrass
(continued)
40
23
23
10
7
10
4
13
7
2
15
15
12
2
5
3
3
1 1
5
3
2
6
2
1
2
1.6
1.3
0.6
0.4
0.2
0
0
0
0
0
0
0
0.0
0.0
0.0
4.9
24. 1
10.4
8.2
4.4
4.0
3.6
3.3
2.6
2.2
2.2
2. 1
.8
.8
.3
. 1
.0
.0
.0
.0
.0
.0
0.9
0.9
0.9
0.8
-------
APPENDIX TABLE C-12. (continued)3
Scientific name
Frequency occurrence
Aggregate percent"
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
(134) ( .) ( .) (134) ( .) ' ( .)
Smi lax spp.
Rumex cr i spus
Rubus spp.
Plantago lanceolata
Nymphaea odorata
(Castalia)
lily
sour dock
bramble
English plantain
• white water lily
1 0
1
1
1
1
0
0
0
0
.0
.0
.0
.0
.0
Total plant material
94.5
Unpublished data from Rawls (in prep.).
>
As defined by Swanson et al. (1974).
NJ
Ul
-------
APPENDIX TABLE C-13. FOOD ITEMS OF PINTAILS IN CHESAPEAKE BAY DURING THE PERIOD 1960 - 19693
KJ
ON
Scientific name
Goni obasi s spp. '
Palaemonetes spp.
Macoma balthica
Physa spp.
Polychaeta
Coleoptera
Planorbi dae
Formicidae
Zea mays
Polygonum pensylvanicum
Pennisetum spp.
Ruppia maritima
Myriophyllum spicatum
Hordeum vulgare
Panicum di chotomi f lorum
Eleocharis obtusa
Prunus serotina
Grami neae
Myrica cerifera
Myrica pensylvanica
Polygonum lapathi f oli urn
Sci rpus val i dus
Echinochloa crusgalli
Cyperus strigosus
Potamogeton perfoliatus
Digitaria sanguinalis
Digitaria Ischaemum
Nyssa sylvatica (biflora)
Enteromorpha spp.
Amaranthus hybridus
Digitaria filiformis
Solanum carolinense
Sparganium americanum
Scirpus americanus
Echinochloa Ualteri
Cladium jamaicense
Potamogeton pectinatus
Leersia oryzoides
Rhus Copal linum
Cyperus esculentus
_
Common name
snai 1
grass shrimp
Baltic macoma
sna i 1
polychaete
beetle
orb snail
ant
Total animal material
corn
smar tweed
feathertop
widgeongrass
Eurasian watermilfoil
barley
panic grass
blunt spikerush
ui Id cherry (black cherry)
grasses
wax-myrtle
bayberry
nodding smartweed
softstem bulrush
barnyard grass
gal i ngale
redhead grass
crab grass
crab grass
black gum (sour gum)
filamentous green algae
prince's feather
crab grass
horse-nettle
eastern burreed
common threesquare
sawgrass
sago pondweed
cut grass
sumac
gal i ngale
(continued)
Frequency occu
Gizzard Gullet
(47) ( .)
2
2
2
2
2
2
2
2
.
53
23
11
17
23
4
19
13
4
4
1 1
4
15
15
15
6
13
23
6
4
2
9
11
2
6
6
2
4
2
2
2
2
rrence Aggregate pe
Unknown Gizzard Gullet
( .) (47) ( .)
1.7
0.8
0.4
0.2
0.2
0.2
0.0
0.0
3.6
28.5
9.7
9.5
.. . 6.1
5.6
4.3
3.8
3.0
2.4
2.1
2. 1
2. 1
2.0
.9
.8
.5
.4
.4
.0
0.8
0.6
0.6
0.5
0.5
0.4
0.4
0.4
0.3
0.2
0.2
0.2
0. 1
rcentb
Unknown
( .)
.
t
.
.
.
,
•
.
•
•
•
.
.
•
.
.
.
.
.
.
.
.
. .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
-.
.
-------
APPENDIX TABLE C-13. (continued)'
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 47) (.)(.) ( 47) ( .) ( .)
Scirpus Olneyi
Setar i a Faberi i
Rumex obtusi fol i us
Polygonum Persicaria
Plantago lanceolata
Ambrosia artemi si i folia
Zannichellia palustris
Eleocharis quadrangulata
Cladium mariscoides
Lolium perenne
Paspalum laeve
Setaria geniculata
Amaranthus hybridus
Acnida cannabinus (amaranthus)
Polygonum densiflorum
Phytolacca americana
Lespedeza striata
Lespedeza bicolor
Vitis vulpina (cordifolia)
Cephalanthus occidental! s
olney threesquare
foxtail grass
bitter dock
smartweed
English plantain
ragweed
horned pon'dweed
squarestem spikerush
twi g-rush
Engli sh rye grass
grass
foxtail grass
prince's feather
tidemarsh waterhemp
southern smartweed
pokeweed
Japanese clover
pulse
forest-grape
buttonbush
2
9
2
4
4
2
2
2
2
2
4
2
6
2
2
6
2
2
2
2
0. 1
0. 1
0. 1
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Total plant material
96.4
Unpublished data from Rawls (in prep.).
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-1. FOOD ITEMS OF BUFFLEHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
N)
00
Scientific name
Mulinia lateralis
Mya arcnaria
Nerei s spp.
Macoma balthica
Leptocheirus plumulosus
Rhi thropaneopeus harrisi
Brachi odontes recurvus (Mytilus)
Chi ronomi dae
Cyprinodon variegatus
Lepomis gibbosus
Corophium spp.
Amni col i i dae (Bulimidae)
Fundulus spp.
Palaemonetes pugio
Anguilla rostrata
Cyathura poli-ta
Scarabaeidae
Ani soptera
Apeltes quadracus
Gemma gemma
Gammari dae
Electra crustulenta
Molgula manhattensis
Balanus spp.
Call i nectus sapidus
Arcuatula demissa (Volsella)
Cyathura carinata (polita)
Edotea triloba
Odostomia spp.
Odostomia impressa
Melampus bidentatus
Congeria leucophaeta
Edotea spp.
Potamogeton pectinatus
Zostera marina
Spartina alterniflora (stricta)
Ruppia maritima
Cyperus strigosus
Potamogeton perfoliatus
Common name
duck clam
soft-shelled clam
clam worm
Baltic macoina
amphi pod
white-fingered mud crab
hooked mussel
midge
sheepshead minnow
bluegi 11
amphi pod
swamp snai 1
prawn
American eel
i sopod
scarab beetle
dragonfly
gem clam
scud
lacy crust
sea grape
barnacle
blue crab
Atlantic ribbed mussel
i sopod
i sopod
undetermind animal
odostome
incised odostome
salt marsh snail
Conrad's false mussel
Total animal material
sago pondweed
eelgrass
saltmarsh cordgrass
wi dgeongrass
gali ngale
redhead grass
(conti nued)
Frequency occu
Gizzard Gullet
(30) ( 2)
47
30
30
17
20
33
17
3
3
3
7
7
3
10
3 50
7
3
3
3
7
7
7
3
3
3
3
3
7
3
13
3
3
7
3
93 50
17 50
7
3
53
3
27
rrence Aggregate percent
Unknown Gizzard Gullet Unknown
( .) (30) (2) ( .)
17.0
10.9
7.8
7.2
5.8
4.0
3.6
3.3
3.0
2.7
2.2
1.7
1.3
1.3
. . 1.3 50.0
1.2
1.1
1.1
0.9
0.7
0.4
0.3
0.2
0.2
0.1
0.0 .
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0 .
79.2 50.0
9.2 50.0
3.8
3.3
2.6 . .
1.1
0.4
-------
APPENDIX TABLE D-1. (continued)
NJ
VO
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown
( 30) ( 2) ( .)
Gizzard Gullet Unknown
( 30) (2) ( .)
Zannichellia palustris
Robinia Psuedoacacia
Rhus radicans
Echinochloa Walteri
Panicum di chotomi f lorum
P a spa 1 urn ci 1 i at i f ol i urn
Setaria glauca
Zea mays
Distichlis spicata
Polygonum punctatum
Liquidambar styraciflua
Prunus serotina
Vi taceae
horned pondweed
black locust
poison ivy - poison oak
panic grass
foxtail grass
corn
salt grass
dotted smartweed
sweet gum (red gum)
wild cherry (black cherry)
grape
undetermined vegetation
13
7
3
3
3
3
3
3
3
3
7
3
3
3
0.2
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Total plant material
80
50
20.8
50.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-2. FOOD ITEMS OF COMMON GOLDENEYES IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet
(21) ( 1)
Unknown
( 2)
Gizzard Gullet
( 21) ( 1)
Unknown
( 2)
Littorina irrorata
Crustacea
Gammarus palustris
Trichoptera
Gobiosoma spp.
Brevoortia tyrannus
Opsanus tau
Brachjodontes recurvus (Mytilus)
Mulinia lateralis
Rhithropaneopeus harrisi
Mya arenaria
Macoma balthica
Palaemonetes pugio
Furtdulus heteroclites
Rangia cuneata
Balanus spp.
Lepomis macrochirus
Erichsonella attenuata
Bairdiella chrysura
Apeltes quadracys
Macoma mitchelli (M. phenax)
Gammarus mucronatus
Amphipoda
Balanus eburneys
Gobiosoma bosci
Zygoptera
Gastropoda
Odostomia spp.
Amnicoliidag (Bulimidae)
Congeria leucophaeta
Nereis spp.
Gammarus spp.
Corophium spp.
Scarabaei dae
Curculionidae
Zea mays
Potamogeton pectinatus
Ruppia maritima
marsh periwinkle
crustacean
scud
caddi sf ly
undetermined fish
naked goby
Atlantic menhaden
oyster toadfish
hooked mussel
duck clam
white-fingered mud crab
soft-shelled clam
Baltic macoma
prawn
brackish water clam
barnacle
bluegi11
i sopod
siIver perch
Mitchell's clam
scud
scud, sideswimmer
ivory barnacle
goby
damselfly
undetermind animal
snail, limpet
odostome
swamp snail
Conrad's false mussel
clam worm
scud
amphi pod
scarab beetle
snout beetle
Total animal material
corn
sago pondweed
widgeongrass
(conti nued)
33
48
52
19
52
.29
19
14
24
10
5
5
10
5
10
5
5
5
5
5
5
14
14
5
10
5
5
5
5
100
24
19
52
50
50
100
50
50
100
50
50
100
100
100
50
0
100
50
100
12. 1
10.0
8.6
8.3
7.9
6.4
6.4
5.7
2.8
2.7
2.6
0.5
0.2
0
0
0
0
0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
74.9
9.6
5.8
4.4
0.0
0.0
3.5
1.0
0.0
5.0
25.0
2.5
2.5
isio
41.5
0.0
100.0
100.0
-------
APPENDIX TABLE D-2. (continued)
Scientific name
Frequency occurrence
Aggregate percent0
Common name
Gizzard Gullet Unknown
( 21) (1) (2)
Gizzard Gullet Unknown
(21) ( 1) . ( 2)
Liquidambar styraciflua
Panicum dichotomiflorum
Potamogeton perfoliatus
Hprdeum vulgare
Pinus Taeda
Rhodophyceae
Cyperus esculentus
Quercus spp.
Polygonum densiflorum
Phytolacca americana
Rybus spp.
Vitaceae
Ambrosia artemisiifolia
sweet gum (red gum)
panic grass
redhead grass
barley
loblolly pine
red algae
gali ngale
oak
southern smartwiaed
pokeweed
bramble
grape
ragweed
Total plant material
2
-------
APPENDIX TABLE D-3. FOOD ITEMS OF CANVASBACKS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
(273) ( 68)
Unknown
( 45)
Gizzard Gullet
(273) ( 68)
Unknown
( 45)
u>
Bittium variym
Odostomia trifida
Amnicoliidae (Bulimidae)
Pelecypoda (Bivalvia)
Cyathura carinata (polita)
Gammarus spp.
Molgula spp.
Macoma balthica
Mya arenaria
Rangia cuneata
Leptocheirus plumulosus
Nereis spp.
Rhithropaneopeus harrisi
Macoma mitchelli (M. phenax)
Balanus spp.
Congeria leucophaeta
Cyathura polita
Nerei s succinea
Gammarus tigrinus
Aori dae
Pori fera
Odostomia spp.
Retusa canaliculata (Acteocina)
Brachiodontes recurvus (Mytilus)
Bittium spp.
Gemma gemma
Nulinia lateral is
Polychaeta
Gammaridae
Xanthidae (Pilumnidae)
Scarabaei dae
Chalepus dorsalis
Vespa spp.
Hordeym vulgare
Spartina spp.
Triticum aestivum
Myrica spp.
Crataegus spp.
Ipomoea hederacea
variable bittium
tripartite odostome
swamp snail
bi valve
i sopod •
scud
sea grape
Baltic macoma
soft-shelled clam
brackish water clam
amphi pod
clam worm
white-fingered mud crab
Mitchell's clam
barnacle
undetermind animal
Conrad's false mussel
i sopod
clam worm
scud
sponge
odostome
channeled barrel bubble
hooked mussel
gem clam
duck clam
polychaete
scud
mud crab
scarab beetle
Total animal material
barley
cordgrass
wheat
wax-myrtle
hawthorn
morning glory
(continued)
93
5
10
8
10
4
6
2
1
1
2
0
1
1
0
1
0
2
0
0
1
0
0
0
0
0
0
99
76
16
13
3
3
16
1
9
3
4
1
2
2
2
4
2
29
18
2
93
2
7
2
2
2
4. 1
2.5
1.8
0.8
0.6
0.4
0.3
0.2
0.2
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
91.4
0.0
69! 1
6.7
0.*6
0. 1
0.8
2.3
0.0
0.6
0.6
0.0
0.0
0.0
81.0
0.0
o!o
0.0
0.0
0.0
0.0
0.0
41.3
21.4
o!s
0. 1
0.2
66.2
0.0
4.2
0.0
0.0
0.0
-------
APPENDIX TABLE D-3. (continued)
Frequency occurrence
Aggregate percent
Scientific name
Zea mays
Potamogeton perfoliatus
Sorgum vulgare .
Ruppia maritima
Chlorophyceae
Vallisneria americana (spiralis)
Distichlis spicata
Polygonum punctatum
Zostera marina
Cladium mariscoides
Scirpus spp.
Polygonum arifolium
Cuscuta spp.
Prunus serotina
Scirpus americanus
Cladophora spp.
Sci rpus Olneyi
Heterantheraj^dubia
Myrica cerirera
Nyssa sylvatica (biflora)
Ilex opaca
Pinus Taeda
Potamogeton pectinatus
Sparganium eurycarpum
Scirpus robustus
Scirpus validus
Carex lurida
Panicum di chotomi f lorum
Sorgum halapense
Amaranthus spp.
Gerani aceae
Rhus Copallinum
Ilex decidua
Vi taceae
Vi t i s spp.
Myr i ophyllum spicatum
Datura stramonium
Common name
corn
redhead grass
grass
wi dgeongrass
green algae
wi Idcelery
salt grass
dotted smartweed
eelgrass
twi g-rush
bulrush
halberdleaf te.ii — thumb
dodder
wild cherry (black cherry)
common threesquare
green algae
olney threesquare
water stai — grass
wax-myrtle
black gum (sour gum)
American holly
loblolly pine
sago pondweed
big burreed
saltmarsh bulrush
softstem bulrush
sedge
panic grass
Johnson grass
amaranth
gerani urn
sumac
holly
grape
grape, wild grape
Eurasian watermilfoil
j imson-weed
Total plant material
Gi zzard
(273)
7
6
1
9
0
0
0
0
0
2
0
1
0
1
3
0
0
1
0
1
0
0
0
0
0
0
1
0
0
0
0
0
23
Gullet
( 68)
12
6
6
3
.
1
.
»
1
.
.
.
.
.
.
.
.
«
,
.
.
,
.
,
.
.
.
.
.
.
.
.
.
.
.
.
•
21
Unknown
( 45)
42
2
.
27
.
2
.
.
2
2
.
.
.
2
2
.
2
.
.
.
.
.
7
.
.
.
.
.
.
.
.
.
.
2
.
.
•
56
Gizzard Gullet
(273) ( 68)
4.1 9.7
1.4 4.4
1.2 4.1
0.6 0.0
0.3
0.3 0.7
0.2
0.
0. 0.0
0.
0.
0.
0.
0.0
0.0
•Q.O
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0'. 0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
8.6 19.0
Unknown
( 45)
22.4
0.3
.
6.7
.
0. 1
.
.
0.0
0.0
.
.
.
0.0
0.0
.
0.0
.
.
.
.
.
0.0
.
.
.
.
.
.
.
.
.
.
0.0
.
.
•
33.8
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-4.
FOOD ITEMS OF GREATER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1970
Frequency occurrence
1979a
Aggregate percent3
Scientific name
Common name
Gizzard Gullet
( 40) ( 8)
Unknown
( .)
Gizzard Gullet
( 8)
Unknown
( .)
Gammarus spp.
Balanidae
Brachiodontes recurvus (Mytilus)
Rangia cuneata
Balanus spp.
Molgula manhattensis
Macoma balthica
Mulinia lateralis
Mya arenaria
Urosalpinx cinerea
Nassarius vibex
Neopanope texana sayi
Congeria leucophaeta
Nassarius obsoletus (Nyanassa)
Littorina irrorata
Cyathura polita
Rhithropaneopeus harrisi
Odostomia spp.
Gemma gemma
Nerei s succi nea
Retusa canaliculata (Acteocina)
Callinectus sapidus
Bittium varium
Hydrobia spp. (Littoridinops)
Macoma mitchelli (M. phenax)
Nereis spp.
Gammarus mucronatus
Balanus improvisus
Myrmica spp.
Odontomyia spp.
Electra crustulenta
Zea mays
Zostera marina
Avena sativa
Cladophora spp.
Secale cereals
Ruppia maritima
Rubus spp.
scud
rock barnacle
hooked mussel
brackish water clam
barnacle
sea grape
Baltic macoma
duck clam
soft-shelled clam
Atlantic oyster drill
mottled dog whelk
mud crab
Conrad's false mussel
mud dog whelk
marsh periwinkle
i sopod
white-fingered mud crab
odostome
gem clam
clam worm
channeled barrel bubble
blue crab
undetermind animal
variable bittium
swamp snai1
Mitchell's clam
clam worm
scud
bay barnacle
ant
lacy crust
Total animal material
undetermined vegetation
corn
eelgrass
oats
green algae
rye
wi dgeongrass
bramble
(conti nued)
65
35
35
8
20
13
15
3
18
5
8
5
5
3
3
10
5
3
10
3
3
3
3
5
8
3
3
3
3
3
98
28
10
3
3
3
25
3
13
13
13
13
13
13
13
13
13
63
13
13
32.2
15.0
6.7
4.0
2.6
2.5
2.3
0.5
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
67.2
16.9
4.4
2.3
2. 1
2.0
1.6
1.3
0. 1
0.0
0.0
4.4
0.5
3.8
1.3
10.0
12.4
62.5
0.0
0. 1
-------
APPENDIX TABLE D-4. (continued)
LO
Ln
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown
( 40) (8) ( .)
Gizzard Gullet Unknown
( 40) (8) ( .)
Ulva lactuca
Enteromorpha intestinalis
Nyssa sylvatica (biflora)
Chlorophyceae
Brornus secalinus
Agrostemma Githago
Rumex cr i spus
Pinus Taeda
Ranunculus acri s
Ilex opaca
Cornus florida
Ipomoea hederacea
Scirpus americanus
Hordeum vulgare
Di sti chli s spi cata
Triticum aestivum
Amaranthus spp.
Rumex spp.
Liquidambar styraciflua
Phaseolus vulgaris
Ambrosia artemi si i foli a
sea lettuce
green alga
black gum (sour gum)
green algae
cheat (chess)
corn-cockle
sour dock
loblolly pine
buttercup
American holly
flowering dogwood
morning glory
common threesquare
barley
salt grass
wheat
amaranth
dock, sorrel
sweet gum (red gum)
common bean
ragweed
Total plant material
3
3 13
5
3 13
3
3
3
3
3
5
3
3
3
3
3
3
3
3
3
3
3
55 100
0.8
0.4 2.5
0.3 ..
0.3 12.5
0.1
0.1
0.1
0.0
0.0
0.0 . .
. ' 0.0
0.0
0.0
.0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
32.8 90.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-5.
FOOD ITEMS OF LESSER SCAUP IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
Frequency occurrence
Scientific name
Aggregate percent
Common name
Gizzard Gullet
(7.6) (18)
Unknown
( .)
Gizzard Gullet
( 76) ( 18)
Unknown
( .)
Rangia cuneata
Brachiodontes recurvus (Mytilus)
Balanus spp.
Maconia balthica
Mulinia latsralis
Mya arenaria
Odostomia spp.
Rhithropaneopeus harrisi
Corophi i dae
Congeria leucophaeta
Corophiym spp.
Urosalpinx cinerea
Nereis spp.
Molgyla manhattensis
,_, Formici dae
w Retusa canaliculata (Acteocina)
GammaridaG
Chi ronomi dae
Nassarius obsoletus (Nyanassa)
Gemma gemma
Hydrobia spp. (Littoridinops)
Curculionidae
Coelenterata (Cnidaria)
Fundulus heteroclites
Pyramidellidae (Turbinellidae)
Nassarius vibex
Melarnpus bidentatus
Pelecypoda (Bivalvia)
Mitrella lunata
Bittium varium
Anachis avara
Pyramidella spp.
Odostomia trifida
Nassarius trivittatus (Nassa)
Nassarius spp.
Amnicola spp.
L i ttori ni dae
Littorina irrorata
Polistes spp.
brackish water clam
hooked mussel
barnacle
Baltic macotna
duck clam
soft-shelled clam
odostome
white-fingered mud crab
scud, sideswimmer
Conrad's false mussel
amphi pod
Atlantic oyster drill
clam worm
sea grape
ant
channeled barrel bubble
scud
mi dge
mud dog whelk
gem clam
swamp snail
snout beetle
hydroi-d, jellyfish
pyramid shell
mottled dog whelk
undetermind animal
salt marsh snail
bi valve
crescent mitrella
variable bittium
greedy dove shell
pyramid shell
tripartite odostome
New England dog whelk
dog whelk
amni cola
periwi nkle
marsh periwinkle
paper wasp
undetermined fish
Total animal material
(conti nued)
32
41
22
8
7
20
18
1
8
1 1
1
17
3
5
12
1
1
5
5
3
1
1
1
3
5
ft
1
3
5
10.9
5.3
5.0
2.9
2.8
2.2
.8
.5
.3
.2
. 1
. 1
.0
0.7
0.6
0.5
0.4
0.4
0.4
0.3
0.2
91
0.0
0.0
0.0
0.0
0.0
0.0
. 0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
42. 1
0.3
i! i
o!o
1.4
-------
APPENDIX TABLE D-5. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 76) ( 18) ( .) ( 76) ( 18) ( .)
Eleusine i.ndica
Chenopodium album
Zea mays
Ruppja maritima
Triticum aestivum
Cladophora spp.
Zostera marina
Ilex decidua
Nyssa sylvatica (biflora)
Scirpus americanus
Polygonum densiflorum
Cyperus spp.
Enteromorpha spp.
Sparganium americanum
Myrica cerifera
Potamogeton perfoliatus
Chlorophyceae
Polygonum punctatum
Rubus spp.
Ilex opaca
Scirpus spp.
Festuca elatior
Ipomoea hederacea
Spartina alterniflora (stricta)
Pinus Taeda
Prunus serotina
Secale cereals
Smilax rotundifolia
Myriophyllum spicatum
Carpinus caroliniana
Ulva spp.
Potamogeton pusillus
Zannichellia palustris
Scirpus robustus
Carex spp.
Polygonum hydropiperoides
Rhus Copallinum
Cuscuta spp.
Iva frytescens
Magnolia virginiana
yard grass
lamb's quarters
corn
wi dgeongrass
wheat
green algae
eelgrass
holly
black gum (sour gum)
undetermined vegetation
common threesquare
southern smartwsed
gali ngale
f ilamentous green algae
eastern burreed
wax-myrtle
redhead grass
green algae
dotted smartweed
bramble
American holly
bulrush
meadow fescue
morning glory
saltmarsh cordgrass
loblolly pine
wild cherry (black cherry)
rye
lily
Eurasian watermiIfoi1
hornbeam (blue beech)
sea lettuce
slender pondweed
horned pondweed
saltmarsh bulrush
sedge
swamp smartweed
sumac
dodder
marsh-elder
sweet bay (swamp bay)
Total plant material
55
22
4
4
3
3
13
5
4
1
1
1
1
8
7
1
1
1
1
1
1
1
1
5
1
1
1
1
1
1
1
1
3
1
1
1
1
1
1
87
6
6
94
100
41.9
2.6
2.3
2. 1
1.3
0.9
0.8
0.6
0.5
0.5
0.4
0.4
0.4
0.4
0.4
0.3
0
0,
0,
0,
0.2
0.2
0,
0,
0,
0.
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
57.9
93
98.6
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-6. FOOD ITEMS OF REDHEADS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
oo
Frequency occurrence
Scientific name
Crepidula fornicata
Erichsonella attenuata
Electra crustulenta
Macoma mitchelli (M. phenax)
Molgula manhattensis
Rangia cuneata
Littorina i rrorata
Pelecypoda (Bivalvia)
Balanus spp.
Zostera marina
Polygonum punctatum
Crataegus spp.
Ipomoea hederacea
Ruppia maritima
Myrica cerifera
Common name
common slipper shell
•i sopod
lacy crust
Mitchell's clam
sea grape
brack i sh water clam
marsh peri wi nkle
bi valve
barnacle
Total animal material
eelgrass
dotted smartweed
hawthorn
morning glory
undetermined vegetation
wi dgeongrass
wax-myrtle ,
Total plant material
Gi zzard
( 7)
.
.
14
29
29
14
14
14
86
86
14
14
14
14
29
14
100
Gullet Unknown
( .) (3)
67
33
100
.
• .
33
. .
. .
•
100
100
. .
.
. .
.
.
•
100
Aggregate percent
Gizzard
( 7)
.
.
2.9
0.4
0. 1
0.0
0.0
0.0
3.4
85.0
2.9
2.9
2.9
2.9
0. 1
0.0
96.6
Gullet Unknown
( .) (3)
0.0
0.0
0.0
.
.
0.0
. .
.
•
0.0
100.0
.
.
.
.
'
•
100.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-7. FOOD ITEMS OF GREEN-WINGED TEAL IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
LO
vO
Q
Frequency occurrence Aggregate percent
Scientific name
L i bellu i dae
Asellus spp.
Cor i xi dae
Hymenoptera
Formi ci dae
Coleoptera
Carabi dae
Lepi doptera
Orthoptera
Aphi das
Chironomidae
Pecti natella magnifica
Cyperus albomargi natus
Cyperus erythrorh.i zos
Cyperus odorattes
Zea mays
Sci rpus val i dus
Cephalanthus occi dental i s
Polygonum punctatum
Rhus radicans
Panicum di chotomi f lorum
Cladophora spp.
Polygonum lapathi f ol i urn
Myriophyllum spicatum
Carpinus caroliniana
Sparganium atnericanum
Eleocharis palustris
Polygonum spp.
Potamogeton pectinatus
Elodea spp.
Eleocharis obtusa
Scirpus Olneyi
Carex spp.
Ambrosia artemi si i folia
Lespedeza striata
Plantago spp.
Panicum anceps
Anei lema Kei sak
Common name
common skimmer
undetermind animal
water boatman
bee, wasp, ant
ant
beetle
ground beetle
butterfly, moth
grasshopper, cricket
aphid, plant lice
midge
bryozoan
Total animal material
gali ngale
redroot cyperus
galingale
corn
softstem bulrush
buttonbush
dotted smartweod
poison ivy - poison oak
panic grass
green algae
nodding smartweed
Eurasian watermi Ifoi 1
hornbeam (blue beech)
eastern burreed
common spi kerush
smartweed
sago pondweed
blunt spikerush
olney threesquare
sedge
ragweed
undetermined vegetation
Japanese clover
plantai n
panic grass
marsh day-flower
(conti nued)
Gizzard Gullet
( 29) ( .)
3
3
10 .
3
3
3
3
3
3
3
3
3
7
38
59
59
41
3
41
38
24
17
24
7
14
7
17
7
7
14
3
3
3
3
3
3
3 .
3
7
7
3
f
Unknown Gizzard Gullet Unknown
( .) (29) ( . ) ( .)
3.0
2.6
1.3 .
0.6
0.6
0.6
0.0
0.0 .
.0.0
0.0
0.0
0.0
0.0
8.7
26.3
21.5
5.9
3.3
3.2 . . .
2.6
2.6
2.6 -
2.5
2.3
2.3
2.3
.9
.6
.4 .
.3
.2
0.7
0.7
0.7
0.7 . .
0.7
0.7
0.6
0.6
0.4 . .
0.2
-------
APPENDIX TABLE D-7. (continued)
Scientific name
Frequency occurrence
Aggregate percent'
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 29) ( .) ( .) ( 29) ( .) ( .)
Polygonum Hydropiper
Cyperus strigosus
Digitaria Ischaeinum
Digitaria sanguinalis
Polygonum densiflorum
Eleocharis quadrangulata
Echinochloa crusgalli
Echinochloa Ualteri
Ranunculus bulbosus
Carex festucacea
Carex lurida
Paspalum laeve
Setaria lutescens
Alnus serrulata
Boehemeria cylindrica
Amaranthus spp.
Rubus spp.
Vitis spp.
Cu scuta .vspp.
Verbena Xirticifolia
Nyssa sylvatica (biflora)
Composi tae
-
smartweed
gali ngale
crab grass
crab grass
southern smartweed
squares-tern spikerush
barnyard grass
buttercup
sedge
sedge
grass
f oxtai 1 grass
smooth alder
false nettle
amaranth
bramble
grape, wild grape
dodder
vervai n
black gum (sour gum)
composi te
Total plant material
7
14
7
3
3
3
3
3
3
7
7
3
3
7
3
3 .
3
3
10
3
3
3
100
0.2
0.2 . ' .
0.1
0.1
0.1.
0.0
0.0
0.0 . .
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0 .
0.0
0.0
0.0
o.o . • .
0.0
91.3
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-8. FOOD ITEMS OF BLACK DUCKS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet
( 57) ( 5)
Unknown
( .)
Gizzard Gullet
( 57) ( 5)
Unknown
( .)
Lymnaea columella
Cyathura polita
Di plopoda
Staphyli ni dae
Tri choptera
Ti puli dae
Tabani dae
L i belluidae
Fundulus heteroclites
Arcuatula demissa (Volsella)
Brachiodontes recurvus (Mytilus)
Balanus eburneus
Macoma balthica
Balanus spp.
Gammarus spp.
Melampus bidentatus
Corbicula manilensis
Macoma mitchelli (M. phenax)
Pi si di um spp.
Rhithropaneopeus harrisi
Nereis spp.
Hydrobia spp. (Littoridinops)
Amnicola spp.
Phyllophaga spp.
Heliosoma spp. (Planorbis spp.)
Congeria leucophaeta
Lumbricidae
Amphipoda
Physa spp.
Odostomia spp.
Amnicoliidae (Bulimidae)
Macoma tenta
Isopoda
Erichsonella spp.
Edotea spp.
Orchestia spp.
Corophium spp.
Podocopa
Haliplidae
Coelambus spp.
Curculi oni dae
i sopod
mi 11i ped
rove beetle
caddi sfly
crane fly
horsefly, deerfly
common skimmer
Atlantic ribbed mussel
hooked mussel
ivory barnacl«
Baltic macoma
barnacle
scud
salt marsh snail
Asiatic fresh-water clam
Mitchell's clam
fresh-water clam
white-fingered mud crab
clam worm
swamp snai1
amnicola
June beetle
undetermind animal
orb snai1
Conrad's falsa mussel
scud, sideswimmer
snai 1
pdostome
swamp snai1
narrowed macoma
i sopod
isopod
amphi pod
amphi pod
ostracod
crawling water beetle
snout beetle
5
19
ft
5
11
2
2
11
5
4
2
4
2
2
2
2
5
2
2
2
7
2
2
2
2
2
2
2
2
4
2
2
2
5
20
20
20
20
20
20
20
20
20
40
20
40
3.2
3.0
2.6
2.3
.1.6
1.5
1.3
0.8
0.4
0.4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.2
0.2
0.2
0.0
0.0
0.2
0.0
0.6
0.2
0.0
o!o
0.0
0.0
(conti nued)
-------
APPENDIX TABLE D-8. (continued)
a
Frequency occurrence Aggregate percent
Scientific name
Carabi dae
Elater i dae
Belastoma spp.
Pentatomi dae
Hymenoptera
Formi ci dae
Pyral i dae
Zygoptera
Araneae
Dolomedes spp.
Eleocharis parvula
Pan i cum clandest i num
Andropogon Gerardi
Muhlenbergia frondosa
Boehemeria cylindrica
Chenopodium spp.
Rumex spp.
Acalypha spp.
Galium spp.
Polygonum punctatum
Ruppia maritima
Leersia oryzoides
Panicum dichotomi f lorum
Scirpus robustus
Leptochloa fascicularis
Scirpus Olneyi
Sorgum halapense
Sparqanium americanutn
Polygonum arifolium
Potarnogeton perfoliatus
Polygonum aviculare
Zea mays
Nyssa sylvatica (biflora)
Spartina alterniflora (stricta)
Celtis occidentalis
Pinus Taeda
Distichlis spicata
Polygonum spp.
Anei lema Kei sak
Zannichellia palustris
Common name
ground beetle
click beetle.
stink bug
bee, wasp, ant
ant
pyralid moths
damself ly
spi der
f i shi ng spi der
undetermined fish
Total animal material
dwarf spikerush
beard grass
muhly
false nettle
goosefoot
dock, sorrel
three-seeded mercury
bedstraw, cleavers
dotted smar tweed
ui dgeongrass
cut grass
panic grass
saltmarsh bulrush
olney threesquare
Johnson grass
eastern burreed
halberdleaf teai — thumb
redhead grass
corn
black gum (sour gum)
saltmarsh cordgrass
hackberry
loblolly pine
salt grass
smartweed
marsh day-flower
horned pondweed
(continued)
Gi zzard
( 57)
2
2
5
2
2
5
2
2
2
2
4
58
B
.
,
.
.
.
•
.
35
39
16
23
12
7
9
9
14
9
19
4
12
11
12
16
25
5
5
5
2
Gullet
( 5)
20
20
,
f
f
40
B
.
t
.
•
100
20
20
20
20
20
20
20
20
20
40
.
40
20
20
20
. '
40
•
.
.
.
.
.
Unknown Gizzard
( .) ( 57)
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
.17.4
. .
* •
• •
• •
. .
. ,
. .
. .
9.9
9.6
8.5
5.7
3.4
3.2
2.6
2.6
2.5
2.4
2.4
2.3
2.0
2.0
.9
.8
.3
.3
.3
.3
. 1
Gullet Unknown
(5) ( .)
0.0
0.0
, .
• •
, .
0.0
. .
. .
. ,
. .
• •
1.6
0.0
0.0
0.2
0.4
0.0
0.0
0.0
0.0
0.0
9.0
.
38.0
0.4
.
.
.
.
.
. •
. .
16.0
0.6
.
9.8
.
.
.
.
.
.
-------
APPENDIX TABLE D-8. (continued)
Frequency occurrence
Aggregate percent'
U>
Scientific name
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
(57) (5) ( .) (57) (5) ( .)
Iva frutescens
Carpinus caroliniana
Cladophora spp..
Echinochloa Malteri
Spartina patens
Cephalanthus occidental's
Peltandra virginica
Cornus florida
Carya spp.
Prunus serotina
Ambrosia artemi si i folia
Cyperus erythrorhi zos
Cyperus albomargi natus
Rhus radicaits
Cyperus odorattes
Myrica pensylvanica
Acnida cannabinus (amaranthus)
Polygonum pensylvani cum
Chara spp.
Vi ti s spp.
Setari a Faberi i
Phytolacca americana
Quercus spp.
Polygonum lapathi folium
Cyperus esculentus
Grami neae
Digitaria filiformis
Myrica cerifera
Potamogeton pusillus
Scirpus americanus
Echinochloa crusgalli
Vi taceae
Hibiscus Moscheutos
Crataegus spp.
Sci rpus val i dus
Quercus Phellos
Cornus Atnomum
Paspalum ci li ati foli urn
Smilax rotundifolia
Iris Pseudacorus
Stellaria media
Liquidambar styraci f lua
marsh-elder
hornbeam (blue beech)
green algae .
saltmeadow cordgrass
undetermined vegetation
buttonbush
arrow arum
flowering dogwood
hi ckory
wild cherry (black cherry)
ragweed
redroot cyperua
gal i ngale
poison ivy - poison oak
gali ngale
bayberry
tidemarsh waterhemp
smartweed
muskgrass
grape, wild grape
foxtail grass
pokeweed
oak
nodding smartweed
gali ngale
grasses
crab grass
wax-myrtle
slender pondweed
common threesquare
barnyard grass
grape
rose-mallow
hawthorn
softstem bulrush
wi How-oak
dogwood
lily
watei — flag
chickweed (starwort)
sweet gum (red gum)
(continued)
5 20
9
2
7 20
4
7
7
5
5
5
14 !
5
2
2
12
9
2
4 40
7 20
2
5 40
7
9
9
9
5
2
5 20
12
4
9
9 20
9
4
4
7
2
2
5
2
2
2
4 .
1.1 4
1.0
1.0
1.0 0
1.0
0.9
0.8
0.6
0.6
0.6
0.5
0.4
0.4
0.3
0.3
0.3
0.3
0.3 15
0.2 0
0.2
0.2 0
0.1
0.
0.
0.
0.
0.
0. 3
0.
0.
0.
0. 0
0.
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0
6
4
6
0
2
0
•
-------
APPENDIX TABLE D-8. (continued)
Scientific name
Acalypha rhomboidea
Trifolium repens
Ilex decidua
Ilex opaca
Plantago lanceolata
Aster tenuifolius
Ulva lactuca
Cyperus spp.
Eleocharis obtusa
Eleocharis quadrangulata
Cladium mariscoides
Sci rpus spp.
Carex spp.
Eleusine indica
Digitaria sanguinalis
Panicum virgatum
Setaria lutescens
Muhlenbergia spp.
Smi lax spp.
Discorea villosa
Alnus serrulata
Chenopodium album
Amaranthus spp.
Rumex crispus
Polygonum Hydropiper
Polygonum hydropiperoi des
Polygonum Persicaria
Ranunculaceae
Rosa spp.
Rosa palustr i s
Rubus spp.
Rhus Copallinum
Cuscuta spp.
Composi tae
Bidsns spp.
Aster spp.
Solanum nigrum
Euphorbia spp.
Common name
three-seeded mercury
white clover
holly
American holly
English plantain
sea lettuce
gal i ngale
blunt spikerush
squarestem spikerush
. twig-rush
bulrush
sedge
yard grass
crab grass
panic grass
foxtail grass
lily
wi Id yam
smooth alder
lamb's quarters
amaranth
sour dock
smartweed
swamp smartweed
smartweed
crowfoot
rose
swamp rose
bramble
sumac
dodder
composi te
beggar-ti ck
aster
black ni ghtshade
spurge
Total plant material
Frequency occu
Gizzard Gullet
( 57) ( 5)
7
2 20
2
ft
2
2
2
2
4
2
2
2
ft
2 20
ft 20
2 20
2
2
2
2
2
2 20
2
ft
ft
5
2
2
2
2
5
9
9
2
2
2
2
2
98 100
rrence Aggregate percent
Unknown Gizzard Gullet Unknown
( .) (57) (5) ( .)
0.0
0.0 0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0 0.2
0.0 0.0
0.0 0.0
0.0
0.0
0.0
0.0
0.0
0.0 0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0 .
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
82.6 98. ft
I
As defined by Swan son e-t al. (1974).
-------
APPENDIX TABLE D-9.
FOOD ITEMS OF MALLARDS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
Frequency occurrence
Aggregate percent0
Scientific name
Common name
Gizzard Gullet
( 84) ( 6)
Unknown
( 2)
Gizzard Gullet
(84) ( 6)
Unknown
( 2)
Orchestia agilis
Corophium spp. .
Popillia japonica
Berosus spp.
Macoma balthica
Brachiodontes recurvus (Mytilus)
Balanus spp.
Goniobasis virginica
Arcuatula demissa (Volsella)
Gsmmarus -fasciatus
Corbicula manilcnsis
Corbicula fluminea
Pelecypoda (Bivalvia)
Asellus spp.
Physa spp.
Dolomedes spp.
Melampus bidentatus
Pi si di urn spp.
Sphaeriym spp.
Orchestia spp.
Carabi dae
Trichoptera
Gastropoda
Nerei s spp.
Lumbri ci dae
Crustacea
Cyathura polita
Atnphipoda
Palaemonetes spp.
Chilognatha
Coleoptera
Dyti scus spp.
Hydrophi1i dae
Elateri dae
Tenebri oni dae
Formicidae
Acrididae (Locustidae)
Ti pulidae
Panicum virgatum
amphi pod
amphipod
Japanese beetle)
Baltic macoma
hooked mussel
barnacle
snai 1
Atlantic ribbed mussel
scud
Asiatic fresh-water clam
bi valve
snai 1
fi shi ng spi der
salt marsh snail
fresh-water clam
sphere shell
amphi pod
ground beetle
caddi sfly
undetermind animal
snai1» 1i mpet
clam worm
crustacean
i sopod
scud, sideswimmer
grass shrimp
beetle
predaceous diving beetle
water scavenger beetle
click beetle
darkling beetle
ant
short-horned grasshopper
crane fly
Total animal material
5
2
5
2
4
1
13
1
1
1
2
2
1
5
1
1
2
1
1
2
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
46
17
17
17
17
50
33
33
50
50
panic grass
17
50
17
100
3.0
1. 1
0.9
0.7
0.5
0.4
0.2
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
7.3
0.0
0.0
0.0
0.0
0.2
1.0
0.3
1.5
0.0
0.5
0.0
2.5
3.0
(conti nued)
-------
APPENDIX TABLE D-9. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent'
Gizzard Gullet Unknown
( 84) (6) (2)
Gizzard Gullet Unknown
( 84) ( 6). ( 2)
Spartina cynosuroides
Andropogon spp.
Rhys glabra
Helianthus spp.
Zea mays
Polygonum punctatum
Leersia oryzoides
Stellaria media
Polygonum arifolium
Scirpus Olneyi
Glycine Max
Aneilerna Keisak
Ruppia maritima
Cephalanthus occidentalis
Sorgum halapense
Sparganium americanum
Peltandra virginica
Nyssa sylvatica (biflora)
Carpinus caroliniana
Sci rpus vali dus
Echinochloa crusgalli
Panicum dichotomiflorum
Vigna sinensis
Vallisneria americana (spiralis)
Cyperus erythrorhizos
Cyperys odorattes
leersia vi rgi ni ca
Polygonum pensylvanicum
Potamogeton perfoliatus
Gramineae
Ulva lactuca
Iva frutescens
Cladiutn mariscoides
Liquidambar styraciflua
Pinus Taeda
Proserpinaca palustris
Digitaria sanguinalis
Chenopodium album
Alnus serrulata
Potamogeton spp.
Scirpus robustus
Polygonum spp.
big cordgrass
beard grass
smooth sumac
sunflower
corn
dotted smartweed
cut grass
chickweed (starwort)
halberdleaf teai—thumb
olney threesquare
soy bean
marsh day-flower
wi dgeongrass
buttonbush
Johnson grass
eastern burreed
arrow arum
black gum (sour gum)
hornbeam (blue beech)
softstem bulrush
barnyard grass
panic grass
cow-pea
wiIdcelery
redroot cyperus
galingale
whi te grass
smartweed
redhead grass
grasses
undetermined vegetation
sea lettuce
marsh-elder
twi g-rush
sweet gum (red gum)
loblolly pine
marsh mermaidweed
crab grass
lamb's quarters
smooth al.der
pondweed
saltmarsh bulrush
smartweed
(conti nued)
21
37
19
10
15
6
6
7
17
14
6
19
5
15
13
17
8
10
1
1
2
6
1
11
12
6
4
1
5
8
2
12
1
7
4
4
1
4
5
17
17
17
17
50
33
50
50
17
17
17
17
17
50
17
50
15.8
7.9
7.3
6.0
6.0
3.7
2.8
2.7
2.7
2.4
2.2
2.2
2. 1
.8
.7
.6
.5
.2
.2
.2
.2
. 1
. 1
.0
.0
0.9
0.9
0.8
0.8
0.6
0
0
0
0
0.4
0.4
0.4
0.3
0.3
0.0
0.0
0.0
16.7
32.2
16.8
6.3
0.0
16'.7
0.0
ois
0.0
49.5
10.0
0.0
7.5
-------
APPENDIX TABLE D-9. (continued)
Scientific name
Frequency occurrence
Aggregate percent'
Common name
Gizzard Gullet Unknown
( 84) (6) (2)
Gizzard Gullet Unknown
( 84) (6) (2)
Polygonum hydropiperoides
Polygonum Persicaria
Ranunculus bulbosus
Cornus Amomum
Spartina alterniflora (stricta)
Cyperus esculentus
Eleochari s spp.
Acnida cannabinus (amaranthus)
Polygonum Hydropiper
V'\ taceae
Carex lurida
Rhys Toxicodendron
Scirpus americanus
Carex scoparia
Setaria Faberi i
Myrica cerifera
Ilex opaca
Di gitari a spp.
Cynodon Dactylon
Ampelopsis spp.
Ambrosia trifida
Glyceri a stri ata
Sagittaria latifolia
Polygonum sagittatum .
Cyperus strigosus
Eleocharis palustris
Digitaria filiformis
Quercus spp.
Celtis occidentalis
Polygonum virginianurn (Tovara)
Cyperus albomarginatus
Echinochloa Walteri
Commelina communis
Vi ti s spp.
Rhus radicans
Ilex decidua
Eleocharis quadrangulata
Smilax Waltoni
Quercus palustris
Amaranthus spp.
Polygonum lapathi foli urn
Phytolacca americana
Rubus spp.
swamp smartweed
smartweed
buttercup
dogwood
saltmarsh cordgrass
gali ngale
spi kerush
tidemarsh waterhemp
smartweed
grape
sedge
poi son-oak
common threesquare
sedge
foxtai1 grass
wax-myrtle
American holly
crab grass
bermuda grass (wire grass)
ragweed
manna grass
broadleaf arrowhead
smartweed •
gali ngale
common spikerush
crab grass
oak
hackberry
gali ngale
day-flower
grape, wild grape
poison ivy - poison oak
holly
squarestem spikerush
lily
pi n-oak
amaranth
nodding smartweed
pokeweed
bramble
1
1
2
4
1
5
4
7
1
2
12
4
(ccmti nued)
2
4
4
5
2
2
4
7
1
8
6
6
4
1
1
5
1
1
6
17
17
17
17
50
17
.2
.2
0.3
0.3
0.3
0.3
0.3
0.2
0
0
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0
0
0
0
0
0
0
0
0
0
0
0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.2
2.5 30.0
2.8
3.3
0.2
-------
APPENDIX TABLE D-9. (continued)
.Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
( 84) ( 6) ( 2) ( 84) (6) (2)
oo
Prunus serotina
Carex intumescens
Paspalum ci 1 i at i f oli urn
Smilax rotundifolia
Crataegus spp.
Ilex verti cillata
Vitis vulpina (cordifolia)
Potamogeton pectinatys
Zannichellia palustris
Eleocharis Engelmanni
Scirpus fluviatilis
Carex spp.
Arthraxon hispidus
Eleusine indica
Digitaria Ischaemum
Echinochloa spp.
Fcstuca spp.
Panicum clandestinum
Paspalum spp.
Setaria spp.
Setaria lutescens
Setaria glauca
Sorgum vulgare
Eulali a viminea
Smilax spp.
Discorea villosa
Boehemeria cylindrica
Rumex spp.
Acalypha rhomboidea
Rosa spp.
Vicia spp.
lespedeza spp.
Rhus Copallinum
Abutilon Theophrasti
Cuscuta spp.
Plantago spp.
Compositae
Ambrosia artemisiifolia
Eclipta alba
Carya spp.
wild cherry (black cherry)
lily
hawthorn
black alder (winterberry)
forest-grape
sago pondweed
horned pondweed
river bulrush
sedge
grass
yard grass
crab grass
grass
foxtail grass
foxtail grass
foxtail grass
grass
lily
wild yam
false nettle
dock, sorrel
three-seeded mercury
rose
vetch
bush-clover
sumac
velvet-leaf (pie-marker)
dodder
plantain
composi te
ragweed
composi te
hi ckory
Total plant material
1
1
2
1
1
1
1
1
1
1
1
1
1
1
2
4
1
8
1
1
4
1
1
98
100
100
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
d.o
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
92.7
98.5
97.0
As defined by Swanson et al. (1974).
-------
APPENDIX TABLE D-10,
FOOD ITEMS OF PINTAILS IN CHESAPEAKE BAY DURING THE PERIOD 1970 - 1979
»__>»«•»••<••«•»••«»•• — «M«I>BB»MWWW»»~ M«B»«««WM~~W~~H~>I>»H«V»W«~W~MBI>«W««
Frequency occurrence
Scientific name
Aggregate percent
Common name
Gizzard Gullet
( 27) ( 8)
Unknown
( .)
Gizzard Gullet
( 27) ( 8)
Unknown
( .).
Hydrobia spp. (Littoridinops)
Arcyatula demissa (Volsella)
Modiolus spp. (Volsella)
Cyathura polita
Asellus spp.
Corophium spp.
Podocopa
Dyti sci dae
Canthydrus puncticollis
Hydrophi1i dae
Carabjdae
Acrididae (Locustidae)
Di ptera
Odontomyia spp.
Culicoides spp.
Taban i dae
Corbicula manilensis
L i belluidae
Amnicoliidae (Bulimidae)
Heliosoma spp. (Planorbis spp.)
Pi sidium spp.
Rhithropaneopeus harrisi
Belastoma spp.
Nerei s spp.
Melampus bidentatus
01i gochaeta
Cassidinidea lunifrons
Curculionidae
Gerri dae
Hymenoptera
Formi ci dae
Lepidoptera
Coleophoridae
Orthoptera
Hydracarina (Acarina)
Cyperus esculentus
Setari a Faberi i
Amaranthus hybridus
Liquidambar styraciflua
swamp snai1
Atlantic ribbed mussel
mussel
i sopod
amphipod
ostracod
predaceous
diving beetle
water scavenger beetle
ground beetle
short-horned grasshopper
fly
punky
horsefly, deerfly
Asiatic fresh-water clam
common skimmer
'swamp snail
orb snai1
fresh-water clam
white-fingered mud crab
clam worm
salt marsh snail
aquatic earthworm
snout beetle
water strider
bee, wasp, ant
ant
butterfly, moth
casebearer
grasshopper, cricket
mi te
undetermined fish
Total animal material
galingale
foxtai1 grass
prince's feather
sweet gum (red gum)
(conti nued)
15
4
7
7
4
4
7
4
56
25
13
13
38
25
25
13
13
13
13
25
25
13
13
13
25
13
25
38
13
38
38
13
13
13
13
100
13
13
13
13
3.9
0.4
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
4.8
0.0
0.0
0.0
0.0
0.3
0.4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0. 1
0.0
0.0
0.0
1.9
oo
0.0
0.0
0.0
o.'o
6.0
0.3
0.0
0.0
0.0
-------
APPENDIX TABLE D-10. (continued)
Scientific name
Common name
Frequency occurrence
Aggregate percent0
Gizzard Gullet
( 27) ( 8)
Unknown Gizzard Gullet Unknown
( .) ( 27) (8) ( .)
Cassia fasciculata
Aster puniceus
Aster spp.
Polygonum punctatum
Zea mays
Leersia oryzoides
Echinochloa crusgalli
Acnida cannabinus (amaranthus)
Cephalanthus occidental!s
Panicum dichotomiflorum
Aneilema Keisak
Cyperus albomarginatus
Echinochloa Walteri
Carpinus caroliniana
Pontederia cordata
Sparganium americanum
Phaseolus vulgaris
Polygonum arifolium
Polygonum pensylvanicum
Zannichellia palustris
Nyssa sylvatica (biflora)
Ruppia maritima
Lycopus uniflorus
Cyperus rotundus
Sci rpus vali dus
Peltandra virginica
Polygonum spp.
Cuscuta spp.
Potamogeton perfoliatus
Festuca elatior
Cyperus odorattes
Cyperus strigosus
Eleocharis obtusa
Eleocharis palustris
Eleocharis parvula
Cladium mariscoides
Sci rpus Olneyi
Zizania aquatics
Galium spp.
Cyperus erythrorhizos
Myrica cerifera
Ilex opaca
Spartina alterniflora (stricta)
gum)
partridge-pea (locust-weed)
wild aster
aster
dotted smartweed
corn
cut grass
barnyard grass
tidemarsh waterhemp
buttonbush
panic grass
marsh day-flower
gali ngale
hornbeam (blue beech)
pickerel weed (tuckahoe)
eastern burreed
common bean
halberdleaf teai—thumb
smartweed
horned pondweed
black gum (sour
wi dgeongrass
bugle-weed
galingale
softstem bulrush
arrow arum
smartweed
dodder
redhead grass
meadow fescue
gali ngale
gali ngale
blunt spikerush
common spikerush
dwarf spikerush
twi g-rush
olney threesquare
wiIdri ce
bedstraw» cleavers
redroot cyperus
wax-myrtle
American holly
saltmarsh cordgrass
(conti nued)
67
19
15
15
22
30
22
15
19
22
15
7
26
4
15
15
4
26
4
7
4
44
7
7
22
4
4
11
15
7
7
4
11
11
15
11
13
13
25
75
25
13
38
75
50
13
50
25
13
13
25
38
50
25
25
25
13
38
H.9
14.3
6.7
6.4
6.0
4.9
4.0
4.0
3.6
2.6
2.2
2.0
.9
.8
.7
.7
.5
.3
. 1
.0
.0
.0
.0
.0
0.8
0.7
0.6
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0
0
0.2
0.2
0.0
0.0
0.0
12.5
0.0
0.0
24.4
20.4
7\5
o'.o
0.8
0.3
10.5
4. 1
0.5
0.0
1. 1
o'.o
.3
.3
1.3
o!o
2. 1
-------
APPENDIX TABLE D-10. (continued)
Scientific name
Frequency occurrence
Aggregate percent
Common name
Gizzard Gullet Unknown Gizzard Gullet Unknown
(27) (8) ( .) (27) ( 8) ( .)
Digitaria filiformis
Pinus Taeda
Potamogeton pectinatus
Cladium jamai cense
Scirpus robustus
Digitaria sanguinalis
Ilex decidua
Cyporus Iria
Polygonum densiflorum
Ambrosia artemi si i f ol i a
Scirpus americanus
Carex lurida
Panicum virgatum
Paspalum laeve
Portulaca oleracea
Potamogeton pusillus
Sagittaria spp.
Eleocharis quadrangulata
Cladium spp.
Carex spp.
Carex festucacea
Carex hortnathodes
Carex hyalinolepis
Carex intumescens
Glyceria striata
Setaria spp.
Zizaniopsis miliacea
Alnus serrulata
Quercus spp.
Boehemeria cylindrica
Rumex verti ci 11 i atus
Polygonum Persicaria
Ranunculus bulbosus
Rubus spp.
Rhus radicans
Vi t i s spp .
Cornus Amomum
Compositae
Iva frutescens
Cicuta maculata
crab grass
loblolly pine
sago pondweed
sawgrass
saltmarsh bulrush
crab grass
holly
gal i ngale
southern smartweed
ragweed
common threesquare
sedge
panic grass
grass
purslane
slender pondweed
arrowhead
squarestem spikerush
sedge
sedge
sedge
lake sedge
manna grass
f oxtai 1 grass
southern wild rice
smooth alder
oak
false nettle
watei — dock
smartweed ,
buttercup
bramble
poison ivy - poison oak
grape, wild grape
dogwood
composi te
marsh-elder
watei — hemlock
Total plant material
7
11
4
4
7
7
7
4
7
7
4
7
4
4
4
4
4
7
4
4
7
7
7
4
4
4
4
7
4
4
4
4
4
7
4
4
4
4
4
4
100
38
13
.
.
.
38
,
13
.
38
.
.
13
38
13
.
.
.
.
.
.
.
.
.
.
13
.
.
.
,
25
.
«
38
.
.
.
.
f
50
100
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
95
.
.
.
.
.
.
•
.
.
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.2
1
0
0
0
0
0
0
0
0
0
0
0
94
.5
.0
.
. .
. .
.0
. .
.4
. .
. 1
.
.
.3
. 1
. 1
.
. .
.
.
.
.
.
.
. .
.
.0
.
. .
. .
. .
.0
.
.
.0
.
• *
.
.
. .
.0
.0
As defined by Swansoh et al. (1974).
-------
APPENDIX TABLE E-1. FREQUENCY OCCURRENCE OF UIDGEONGRASS IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-19793
b
Survey area
Lower Choptank River
Manokin, Annemessex R.
Eastern Bay
Chester River
Smith Island (Maryland)
Miles River
Honga River
Wye River
Bloodsworth, South Marsh I.
Bayshore, Hooper Island
Magothy - Severn Rivers
Little Choptank River
Patuxent River
Fishing Bay
Patapsco R., Aberdeen P.G.
Bayshore, Kent Island
South River, Herring Bay
Upper Choptank River
Total
1 9
27.5
24.6
21.4
27.8
47. 1
37.5
30.0
18.2
20.0
26. 1
22.2
10.0
0.0
8.0
1.9
0.0
0.0
0.0
14.7
P e
7 1
(51)
(57)
(28)
(36)
(17)
( 8)
(30)
(11)
(40)
(23)
(27)
(30)
(50)
(25)
(52)
( 8)
(21)
( 9)
(624)
r c e
1 9
35.4
9. 1
20.8
11.1
27.3
50.0
23.3
36.4
2.3
13.0
11. 1
6.7
4.4
0.0
0.0
0.0
0.0
10.0
10.0
n t
7 2
(48)
(55)
(24)
(36)
(11)
( 8)
(30)
(11)
(44)
(23)
(27)
(30)
(45)
(25)
(50)
( 8)
(21)
(10)
(613)
w i •
1 9
12.8
10.7
10.7
8.8
16.7
50.0
10.0
36.4
8.7
4.3
7.4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
6.0
t h
7 3
(47)
(56)
(28)
(34)
(12)
( 8)
(30)
(11)
(46)
(23)
(27)
(30)
(50)
(25)
(50)
( 8)
(21)
(10)
(629)
v e g
1 9
28.6
23.5
21.4
2.9
29.4
50.0
16.7
54.5
4.7
8.7
18.5
0.0
2.0
0.0
0.0
12.5
0.0
0.0
9.8
eta
7 4
(49)
(34)
(28)
(34)
(17)
( 8)
(30)
(11)
(43)
(23)
(27)
(30)
(50)
(25)
(52)
( 8)
(19)
( 9)
(610)
t i (
1 9
2. 1
9.6
11.1
11.1
5.9
25.0
10.3
27.3
4.7
8.7
•
0.0
0.0
0.0
0.0
0.0
0.0
0.0
4.7
D n >
7 5
(47)
(52)
(27)
(36)
(17)
( 8)
(29)
(11)
(43)
(23)
( 0)
(30)
(47)
(24)
(22)
( 8)
(14)
(10)
(552)
a n
1 9
47.8
12.3
37.0
14.3
35.3
42.9
13.8
36.4
2.2
13.0
8.0
10.0
2.0
0.0
0.0
0.0
4.8
0.0
11.5
d s
7 6
(46)
(57)
(27)
(35)
(17)
( 7)
(29)
(11)
(45)
(23)
(25)
(30)
(49)
(25)
(52)
( 8)
(21)
(1.0)
(628)
a m |
1 9
28.6
8.9
11.1
13.9
11.8
50.0
3.3
27.3
2.2
4.3
7.4
6.7
0.0
0.0
0.0
0.0
0.0
0.0
6.7
3 1 e
7 7
(49)
(56)
(27)
(36)
(17)
( 8)
(30)
(11)
(46)
(23)
(27)
(30)
(49)
(25)
(52)
( 8)
(21)
(10)
(638)
s i
1 9
30.6
3.6
11.1
25.0
5.9
50.0
3.3
36.4
0.0
0.0
7.4
3.3
0.0
0.0
0.0
0.0
0.0
0.0
6.6
z e
7 8
(49)
(55)
(27)
(36)
(17)
( 8)
(30)
(11)
(46)
(23)
(27)
(30)
(50)
(25)
(52)
( 8)
(21)
(10)
(636)
( )
1 9
25.5
0.0
7.4
16.7
11.8
0.0
0.0
18.2
0.0
0.0
14.8
3.3
0.0
0.0
0.0
0.0
0.0
0.0
4.6
7 9
(47)
(56)
(27)
(36)
(17)
( 8)
(30)
(11)
(45)
(23)
(27)
(30)
(48)
(24)
(52)
( 8)
(21)
(10)
(631)
Data from the files of MBHRL, Laurel, Maryland.
b
Frequency occurrence of SAV averaged over years, when multiplied by the
determined the sequence of survey areas used above.
extent of shoal habitat «2.44 in at mlw) in an area,
-------
APPENDIX TABLE E-2. FREQUENCY OCCURRENCE OF EELGRASS IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-19793
Survey area
Manokin, Annemessex R.
BloodsMorth, South Marsh I.
Smith Island (Maryland)
Bayshpre, Hooper Island
Honga River
Eastern Bay
Lower Choptank River
Fishing Bay
Little Choptank River
Patuxent River
Total
1
36.
22.
29.
60.
26.
7.
5.
4.
3.
2.
10.
9
8
5
4
9
7
1
9
0
3
0
4
P e i
7 1
(57)
(40)
( 17)
(23)
(30)
(28)
(51)
(25)
(30)
(50)
(624)
r c e
1 9
32.7
15.9
45.5
4.3
16.7
20.8
6.3
4.0
0.0
0.0
7.3
n t
7 2
(55)
(44)
(11)
(23)
(30)
(24)
(48)
(25)
(30)
(45)
(613)
w i
1
10.
2.
0.
0.
0.
0.
0.
0.
0.
0.
1.
^
9
7
2
0
0
0
0
0
0
0
0
1
t h
7 3
(56)
(46)
(12)
(23)
(30)
(28)
(47)
(25)
(30)
(50)
(629)
v e
1
26
9
,11
0
0
0
0
0
0
0
2
g
9
.5
.3
.8
.0
.0
.0
.0
.0
.0
.0
.5
eta
7 4
(34)
(43)
(17)
(23)
(30)
(28)
(49)
(25)
(30)
(50)
(610)
t i <
1 9.
17.3
7.0
17.6
0.0
3.4
3.7
0.0
0.0
0.0
0.0
3. 1
3 n ,
7 5
(52)
(43)
(17)
(23)
(29)
(27)
(47)
(24)
(30)
(47)
(552)
a n
1 9
8.8
0.0
5.9
0.0
3.4
0.0
0.0
0.0
0.0
0.0
1. 1
d s
7 .6
(57)
(45)
(17)
(23)
(29)
(27)
(46)
(25)
(30)
(49)
(628)
a m f
1 9
17.9
2.2
17.6
0.0
0.0
0.0
0.0
0.0
0.0
0.0
2.2
3 1 e
7 7
(56)
(46)
(17)
(23)
(30)
(27)
(49)
(25)
(30)
(49)
(638)
s
1
7
0
5
0
0
0
0
0
0
0
0
i
9
.3
.0
.9
.0
.0
.0
.0
.0
.0
.0
.8
z e (
7 8
(55)
(46)
( 17)
(23)
(30)
(27)
(49)
(25)
(30)
(50)
(636)
)
1
0.
0.
5.
0.
0.
0.
0.
0.
0.
0.
0.
9
0
0
9
0
0
0
0
0
0
0
2
7 9
(56)
(45)
(17)
(23)
(30)
(27)
(47)
(24)
(30)
(48)
(631)
"Data from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the extent of shoal habitat (<2.44 m at mlw) in an area,
determined the sequence of survey areas used above.
-------
APPENDIX TABLE E-3. FREQUENCY OCCURRENCE OF REDHEAD GRASS IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-1979a
Survey area''
Chester River
Eastern Bay
Magothy - Severn Rivers
Louier Choptank River
Patapsco R., Aberdeen P.G.
Wye River
Upper Choptank River
Total
1
44
10
37
3
0
9
1.1
5
9
.4
.7
.0
.9
.0
. 1
. 1
.3
P e i
7 1
(36)
(28)
(27)
(51)
(52)
(11)
( 9)
(624)
' C
1
33
12
7
4
2
0.
10
3
e
9
.3
.5
.4
.2
.0
.0
.0
.4
n t
7 2
(36)
(24)
(27)
(48)
(50)
(11)
(10)
(613)
w i \
1 9
26.5
10.7
18.5
12.8
2.0
18.2
0.0
4. 1
b h \
7 3
(34)
(28)
(27)
(47)
(50)
(11)
(10)
(629)
/eg
1 9
14.7
14.3
18.5
8.2
1.9
18.2
0.0
3.4
eta
7 4
(34)
(28)
(27)
(49)
(52)
(11)
( 9)
(610)
t i <
1 9
16.7
11.1
.
2. 1
0.0
0.0
0.0
1.8
J n ,
7 5
(36)
(27)
( 0)
(47)
(22)
(11)
(10)
(552)
a n
1 9
17.1
11.1
12.0
4.3
0.0
0.0
0.0
2.2
d s
7 6
(35)
(27)
(25)
(46)
(52)
(11)
(10)
(628)
a m |
1 9
8.3
3.7
7.4
0.0
5.8
0.0
0.0
1.4
3 1 e
7 7
(36)
(27)
(27)
(49)
(52)
(11)
(10)
(638)
s i
1 9
19.4
7.4
14.8
0.0
3.8
0.0
0.0
2.4
z e 1
7 8
(36)
(27)
(27)
(49)
(52)
(1 1)
(10)
(636)
1 9
13.9
11.1
14.8
2. 1
1.9
0.0
0.0
2.2
7 9
(36)
(27)
(27)
(47)
(52)
(11)
(10)
(631)
from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years* when multiplied by the extent of shoal habitat (<2.44 m at mlw) in an area,
determined the sequence of survey areas used above.
-------
APPENDIX TABLE E-4. FREQUENCY OCCURRENCE OF SAGO PONDWEED IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-1979C
Survey area
Chester River
Eastern Bay
Magothy - Severn Rivers
Manokin, Annemessex R.
Louer Choptank River
Bloodsujorthr South Marsh I.
Bayshore, Hooper Island
Smith Island (Maryland)
Honga River
Little Choptank River
Patapsco R., Aberdeen P.G.
Total
1 9
5.6
0.0
7.4
1.8
2.0
2.5
0.0
0.0
0.0
3.3
0.0
1.3
P e i
7 1
(36)
(28)
(27)
(57)
(51)
(40)
(23)
(17)
(30)
(30)
(52)
(624)
r c
1
2
16
7
12
4
6
30
27
10
6
2
5
e
9
.8
.7
.4
.7
.2
.8
.4
.3
.0
.7
.0
.7
n t
7 2
(36)
(24)
(27)
(55)
(48)
(44)
(23)
(11)
(30)
(30)
(50)
(613)
M
1
5
10
11
1
8
6
0
8
3
0
0
2
i •<
9
.9
.7
. 1
.8
.5
.5
.0
.3
.3
.0
.0
.9
fc h \
7 3
(34)
(28)
(27)
(56)
(47)
(46)
(23)
(12)
(30)
(30)
(50)
(629)
/eg
1 9
14.7
3.6
7.4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.3
eta
7 4
(34)
(28)
(27)
(34)
(49)
(43)
(23)
(17)
(30)
(30)
(52)
(610)
t i <
1 9
0.0
0.0
.
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
> n ,
7 5
(36)
(27)
( 0)
(52)
(47)
(43)
(23)
(17)
(29)
(30)
(22)
(552)
a
1
5
3
0
0
0
0
0
0
0
0
0
0
n
. 9
.7
.7
.0
.0
.0
.0
.0
.0
.0
.0
.0
.5
d s
7 6
(35)
(27)
(25)
(57)
(46)
(45)
(23)
(17)
(29)
(30)
(52)
(628)
a
1
11
3
14
0
0
0
0
0
0
0
0
1
m t
9
. 1
.7
.8
.0
.0
.0
.0
.0
.0
.0
.0
.4
3 1 e
7 7
(36)
(27)
(27)
(56)
(49)
(46)
(23)
(17)
(30)
(30)
(52)
(638)
s i
1 9
13.9
0.0
14.8
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.4
z e (
7 8
(36)
(27)
(27)
(55)
(49)
(46)
(23)
(17)
(30)
(30)
(52)
(636)
)
1 9
5.6
0.0
3.7
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.5
7 9
(36)
(27)
(27)
(56)
(47)
(45)
(23)
(17)
(30)
(30)
(52)
(631)
Data from the files of MBHRL, Laurel* Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the
determined the sequence of survey areas used above.
extent of shoal habitat (<2.44 m at mlw) in an area*
-------
APPENDIX TABLE E-5. FREQUENCY OCCURRENCE OF EURASIAN WATERMILFOIL IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-79*
Survey area"
Susquehanna Flats
Chester River
Patapsco R., Aberdeen P.G.
Eastern Bay
Bayshore, Kent County
Magothy - Severn Rivers
Sassafras River
Northeast* Elk, Bohemia R.
Patuxent River
Total
1
27
33
5
0
16
0
10
0
0
3
9
.3
.3
.8
.0
.7
.0
.0
.0
.0
.8
P e i
7 1
(22)
(36)
(52)
(28)
(12)
(27)
(10)
(20)
(50)
(624)
- c e
•1 9
0.0
11.1
2.0
4.2
0.0
3.7
0.0
0.0
0.0
1. 1
n t
7 2
(30)
(36)
(50)
(24)
( 6)
(27)
(10)
(23)
(45)
(613)
N i -I
1 9
0.0
2.9
2.0
3.6
0.0
0.0
0.0
0.0
0.0
0.5
t h <
7 3
(30)
(34)
(50)
(28)
( 12)
(27)
(10)
(23)
(50)
(629)
\i e
1
16.
0.
P-
3.
0.
0.
10.
0.
0.
1.
g
9
7
0
0
6
0
0
0
0
0
1
eta
7 4
(30)
(34)
(52)
(28)
(12)
(27)
(10)
(23)
(50)
(610)
t i <
1 9
13.3
0.0
0.0
0.0
0.0
•
0.0
0.0
0.0
0.7
3 n >
7 5
(30)
(36)
(22)
(27)
( 12)
( 0)
(10)
(22)
(47)
(552)
a
1
10.
0.
1.
3.
0.
4.
0.
0.
0.
1.
n
9
3
0
9
7
0
0
0
0
0
0
d s
7 6
(29)
(35)
(52)
(27)
(12)
(25)
(10)
(22)
(49)
(628)
a m |
1 9
6.7
2.8
3.8
3.7
0.0
0.0
0.0
0.0
0.0
0.9
3 1 e
7 7
(30)
(36)
(52)
(27)
( 12)
(27)
(10)
(23)
(49)
(638)
s i
1 9
3.4
2.8
0.0
7.4
0.0
0.0
0.0
0.0
0.0
0.6
z e i
7 8
(29)
(36)
(52)
(27)
(12)
(27)
(10)
(22)
(50)
(636)
C )
1 9
6.9
16.7
3.8
11.1
0.0
0.0
0.0
4.3
2. 1
2.4
7 9
(29)
(36)
(52)
(27)
(12)
(27)
(10)
(23)
(48)
(631)
aData from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the
determined the sequence of survey areas used above.
extent of shoal habitat (<2.44 m at mlw) in an area,
-------
APPENDIX TABLE E-6. FREQUENCY OCCURRENCE OF HORNED PONDWEED IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-19793
Survey area
Lower Choptank River
Chester River
Eastern Bay
Wye River
Magothy - Severn Rivers
Miles River
Little Choptank River
Patuxent River
Bayshore, Hooper Island
Honga River
South River, Herring Bay
Total
1
0
0
0
0
0
0
0
0
0
0
0
0
9
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
P e i
7 1
(51)
(36)
(28)
(11)
(27)
( 8)
(30)
(50)
(23)
(30)
(21)
(624)
r c e
1 9
20.8
0.0
8.3
27.3
0.0
12.5
3.3
0.0
0.0
0.0
0.0
2.8
n t
7 2
(48)
(36)
(24)
(11)
(27)
( 8)
(30)
(45)
(23)
(30)
(21)
(613)
w i I
1 9
0.0
2.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.2
fc h v
7 3
(47)
(34)
(28)
(11)
(27)
( 8)
(30)
(50)
(23)
(30)
(21)
(629)
e g
1 9
0.0
0.0
0.0
0.0
3.7
0.0
0.0
0.0
0.0
0.0
0.0
0.2
eta
7 4
(.49)
(34)
(28)
(11)
(27)
( 8)
(30)
(50)
(23)
(30)
(19)
(610)
t
1
0
0
0
0
0
0
0
0
0
0
0
i <
9
.0
.0
.0
.0
.
.0
.0
.0
.0
.0
.0
.0
3 n ,
7 5
(47)
(36)
(27)
(11)
( 0)
( 8)
(30)
(47)
(23)
(29)
(14)
(552)
a n
19
17.4
5.7
14.8
36.4
4.0
14.3
0.0
0.0
4.3
3.4
0.0
3.5
d s
7 6
(46)
(35)
(27)
( 11)
(25)
( 7)
(30)
(49)
(23)
(29)
(21)
(628)
a
1
0
19
3
0
3
0
3
2
0
0
0
1
m i
9
.0
.4
.7
.0
.7
.0
.3
.0
.0
.0
.0
.7
3 1 e
7 7
(49)
(36)
(27)
( 11)
(27)
( 8)
(30)
(49)
(23)
(30)
(21)
(638)
s i
1 9
0.0
19.4
0.0
9. 1
3.7
0.0
0.0
2.0
0.0
0.0
0.0
1.6
2 e (
7 8
(49)
(36)
(27)
(11)
(27)
( 8)
(30)
(50)
(23)
(30)
(21)
(636)
)
1 9
0.0
0.0
3.7
0.0
3.7
0.0
0.0
0.0
0.0
0.0
4.8
0.5
7 9
(47)
(36)
(27)
( 11)
(27)
( 8)
(30)
(48)
(23)
(30)
(21)
(631)
Data from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the
determined the sequence of survey areas used above.
extent of shoal habitat (<2.44 m at mlw) in an area,
-------
APPENDIX TABLE E-7. FREQUENCY OCCURRENCE OF UILDCELERY IN MARYLAND WATERFOWL SURVEY AREAS DURING THE YEARS 1971-1979C
Survey area
Patapsco R., Aberdeen P.G.
Susquehanna Flats
Chester River
Magothy - Severn Rivers
Sassafras River
Northeast, Elk, Bohemia R.
Bayshore, Kent County
Total
1
0.
45.
2.
7.
.20.
5.
8.
2.
9
0
5
8
4
0
0
3
7
Per
7 1
(52)
(22)
(36)
(27)
(10)
(20)
(12)
(624)
c e
1 9
0.0
3.3
0.0
0.0
0.0
0.0
0.0
0.2
n t
7 2
(50)
(30)
(36)
(27)
(10)
(23)
( 6)
(613)
w i
1
2.
0.
2.
3.
0.
0.
0.
0.
\
9
0
0
9
7
0
0
0
5
t h v
7 3
(50)
(30)
(34)
(27)
(10)
(23)
(12)
(629)
e g
1 9
5.8
0.0
5.9
0.0
0.0
0.0
0.0
0.8
eta
7 4
(52)
(30)
(34)
(27)
(10)
(23)
(12)
(610)
t i
1
9.
0.
8.
.
0.
0.
0.
0.
(
9
1
0
3
0
0
0
9
J n ,
7 5
(22)
(30)
(36)
( 0)
( 10)
(22)
(12)
(552)
a n
1 9
3.8
0.0
2.9
4.0
0.0
0.0
0.0
0.6
d s
7 6
(52)
(29)
(35)
(25)
(10)
(22)
(12)
(628)
a m f
1 9
3.8
0.0
5.6
0.0
0.0
0.0
0.0
0.6
3 1 e
7 7
(52)
(30)
(36)
(27)
(10)
(23)
(12)
(638)
s i
1 9
3.8
0.0
2.8
0.0
0.0
0.0
0.0
0.5
z e (
7 8
(52)
(29)
(36)
(27)
(10)
(22)
(12)
(636)
)
1 9
5.8
0.0
2.8
7.4
0.0
0.0
0.0
1.0
7 9
(52)
(29)
(36)
(27)
(10)
(23)
(12)
(631)
Data from the files of MBHRL, Laurel, Maryland.
Frequency occurrence of SAV averaged over years, when multiplied by the extent of shoal habitat (<2.44 m at mlw) in an area,
determined the sequence of survey areas used above.
-------
APPENDIX TABLE F-1. MARYLAND WHISTLING SWAN POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
01
10
D e n s i t ya
Percent
Survey area
Lower Choptank River
Chester River
Eastern Bay
Little Choptank River
Miles Ri ver
South River - Herring Bay
Bayshore, Hooper Island
Susquehanna Flats
Upper Choptank River
Wye River
Patapsco River - Aberdeen P.G.
Magothy - Severn Rivers
Patuxent River
Bayshore, Kent Island
Hon'ga River
Bayshore, Kent County
Bloodsworth - South Marsh Islands
Sassafras River
Bayshore, 'Calvert County
Northeast - Elk - Bohemia Rivers
Nanticoke - Wicomico Rivers
Manokin, Big - Little Annemessex R.
Smith Island
Fi shi ng Bay
Mean
7415.8
5055.4
4988.4
2460. 1
1880.3
1267.3
990.6
767.5
863.7
843.8
618.6
720.6
723.5
400.6
336.2
221.5
145.3
127.2
105.0
59.4
49.4
57.8
87.5
12.6
S.E.
806.7
570.4
615.4
387.4
189.8
169.8
163.5
204.8
122.8
131.9
166.0
181.5
147. 1
101.8
102.6
48.8
37.7
33.3
32. 1
20.3
14.7
56.2
49. 1
8.5
C.V.
43.5
45. 1
49.4
63.0
40.4
53.6
66.0
106.7
56.9
62.5
107.3
100.8
81.3
101.7
122.0
88.2
103.6
104.7
122.2
136.5
119.4
388.6
224.2
270.2
Mean
563.5
648.9
627.2
327.4
870.9
282.6
174.9
95.0
416.6
475.4
35.9
160. 1
95.6
180.9
48.8
90.6
12.7
77.2
38. 1
13. 1
6.7
4.2
20.5
2.0
S.E. .
61.3
73.2
77.4
51.5
87.9
37.9
28.9
25.4
59.2
74.3
9.6
40.3
19.4
46.0
14.9
20.0
3.3
20.2
11.6
4.5
2.0
4. 1
11.5
1.4
Slo
27
32
44
44
17
10
6
pe
.2
.2
.9
. 1
. 1
.9
.3
Mean
21.9
15.3
14.4
7.6
5.7
4. 1
2.9
2.8
2.8
2.6
2.2
2.2
2. 1
1.4
1.2
0.7
0.5
0.4
0.3
0.2
0.2
0.2
0.2
0.0
S.E.
1.4
1.0
1.2
1.0
0.5
0.6
0.4
1.0
0.5
0.4
0.6
0.5
0.4
0.3
0.5
0.
0.
0.
0.
0.
0.0
0.2
0. 1
0.0
C.
25
26
33
53
32
57
59
144
66
66
114
87
66
98
170
88
103
100
118
148
117
389
225
267
V. Slope
.8
.4
.2 0.6
.6
.3
. 1
. 1
.7
.5 .
.5
.4
.2
.6
.2
.4
.3
.0
.5
.9
.4
.0
.8
.9
.8
Densities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-2. MARYLAND CANADA GOOSE POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
D e n s i t y£
Percent
Survey area
Chester River
Lower Chop-tank River
Sassafras River
Wye River
Eastern Bay
Bayshore, Kent County
Mi les Ri ver
Upper Choptank River
Bayshore, Hooper Island
Northeast - Elk - Bohemia Rivers
Honga River
Nanticoke - Ulicomico Rivers
Little Choptank River
Bayshore, Kent Island
Bloodsworth - South Marsh Islands
Smith Island
Manokin, Big - Little Annemessex R.
Susquehanna Flats
Fishing Bay
Patapsco River - Aberdeen P.G.
Patuxent River
Magothy - Severn Rivers
South River - Herring Bay
Bayshore, Calvert County
Mean
65490.6
35713.5
23831.2
16933.6
19008.5
15677.9
12671.6
8481.8
5151.9
6025.0
4813.2
4224. 1
3872.6
2419.8
2990.3
2590.6
2084.4
1207.8
1111.2
567.8
1375.9
310.9
69.6
1.6
S.E
7912.
5360.
2632.
3450.
4370.
3077.
2885.
1415.
795.
1498.
932.
1362.
982.
972.
709.
660.
526.
279.
386.
310.
446.
125.
34.
1.
0
4
0
0
7
7
7
9
9
0
7
0
7
6
7
0
0
9
5
1
3
7
9
6
C.V.
48.3
60.0
44.2
81.5
92.0
78.5
91. 1
66.8
61.8
99.5
77.5
129.0
101.5
160.8
94.9
101.9
100.9
92.7
139. 1
218.4
129.8
161.8
200.8
400.0
Mean
8405.9
. 2714.0
14460.7
9540. 1
2390. 1
6414.8
5869.2
4091.6
909.4
1330.6
698.0
573.5
515.3
1093.0
261.3
607.4
150.9
149.5
177.9
33.0
181.9
69.1
15.5
0.6
S.E.
1015.5
407.4
1597. 1
1943.7
549.6
1259.3
1336.6
683.0
140.5
330.8
135.3
184.9
130.8
439.3
62.0
154.8
38. 1
34.7
61.9
18.0
59.0
27.9
7.8
0.6
Slopeb
768.6
278.6
878.2
323.6
726.2
790.3
506.7
243.5
58.8
70.5
24.5
33.0
16.4
3.4
Mean
25.3
12.7
10.0
6.5
6.3
5.8
4.2
3.0
2.0
.8
.7
.5
.4
.3
.2
. 1
0.7
0.6
0.5
0.4
0.4
0. 1
0.0
0.0
S.E.
1.2
0.9
0.9
1. 1
1.0
0.9
0.7
0.4
0.4
0.3
0.3
0.4
0.2
0.5
0.2
0.3
0. 1
0.2
0.2
0.3
0. 1
0.0
0.0
0.0
C.V. <
18.4
27.5
37.2
65.2
63.5
59.6
67.9
50.2
76.7
75.7
63.0
114.7
67.0
142.4
85.6
126.3
64. 1
139.5
136.4
244.8
133.6
142.5
196.0
400.0
Slope
0.4
0.3
0.2
0. 1
Densities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-3.
MARYLAND RUDDY DUCK POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Density3 Percent
Survey areav
Patapsco River - Aberdeen P.G.
Patuxent Ri ver
Bayshore, Calvert County
Lower Choptank River
South River - Herring Bay
Fi shi ng Bay
Susquehanna Flats
Nanticoke - Ulicomico Rivers
Chester River
Magothy - Severn Rivers
Wye River
Manokin, Big - Little Annemessex R.
Eastern Bay
Upper Choptank River
Bloodsworth - South Marsh Islands
Sassafras River
Miles Ri ver
Little Choptank River
Northeast - Elk - Bohemia Rivers
Bayshore, Kent County
Bayshore, Kent Island
Bayshore, Hooper Island
Honga River
(Mean
4111
856
410
346
492
231
412
244
310
185
105
154
141
111
25
25
29
10
1
10
5
21
0
.9
.9
.6
. 1
.8
.4
.5
.8
. 1
.3
.0
. 1
.2
.9
.0
.0
.7
.9
.6
.0
.6
.9 '
.8
S.E.
1982. 1
515.5
222.9
164.7
216.2
113.5
277.9
204.7
176.6
93.7
47.5
93.5
86.6
48.6
19.4
25.0
15.7
6.4
1.6
6.5
5.6
15. 1
0.8
C.V.
192.8
240.6
217. 1
190.3
175.5
196.3
269.5
334.5
227.8
202.2
180.8
242.7
245. 1
173.6
309.8
400.0
211.3
235.6
400.0
261.4
400.0
276.4
400.0
Mean
238
113
148
26
109
37
51
33
39
41
59
1 1
17
54
2
15
13
1
0
4
2
3
0
.7
.3
.9
.3
.9
.0
. 1
.2
.8
.2
.2
.2
.8
.0
.2
.2
.8
.5
.3
. 1
.5
.9
. 1
S.
115
68
80
12
48
18
34
27
22
20
26
6
10
23
1
15
7
0
0
2
2
2
0
E. Slopeb
. 1
. 1
.8
.5
.2
.2
.4
.8
.7
.8
.7 -12.6
.8 -3.3
.9 -5.3
.4
.7
.2
.3 -3.6
.9
.3
.7
.5
.7
. 1
Mean
13.2
6.4
3.6
3.4
2. 1
2. 1
1.5
1.4
1.3
1.3
1.2
0.9
0.7
0.6
0.2
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
S.E.
5. 1
3.6
1.9
1.8
0.8
1.2
0.9
1.0
0.6
1.0
0.7
0.5
0.4
0.3
0.2
0. 1
0. 1
0. 1
0.0
0.0
0.0
0.0
0.0
C.V. Slope
151.5
217. 1
208. 1
201.9
150.6
216.5
240.3
282.7
187.9
281.4
2'14.7
205.4
217.8
180.5
270.0
387.3
198.5
203.7
337.3
216.8
387.3
275.9
387.3
Densities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F~4. MARYLAND SCOTER POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Density3 Percent
Survey area
Bayshore, Calvert County
Eastern Bay
Lower Choptank River
Smith Island
Little Choptank River
Bayshore, Kent Island
Bayshore, Hooper Island
South River - Herring Bay
Patuxent River
Manokin, Big - Little Annemessex R.
Chester River
Miles Ri ver
Bloodsworth - South Marsh Islands
Magothy - Severn Rivers
Nanticoke - Wicomico Rivers
Northeast - Elk - Bohemia Rivers
Upper Choptank River
Honqa R i ver
Fishing Bay
Patapsco River - Aberdeen P.G.
Susquehanna Flats
Bayshore, Kent County
Mean
8707.5
1846.3
537.8
496.3
411.8
243.9
525.6
463. 1
493.8
171.9
98.9
99. 1
178.6
187.5
18.4
18.8
7.8
14. 1
1.9
0.8
1.6
0.8
S.E.
7825.4
1396.2
233.2
271.4
185.8
102.5
404.8
381.2
266. 1
76.3
45.6
60.4
102.6
187.5
9. 1
18.8
6.3
12.5
1.6
0.8
1.6
0.8
C.
359
302
173
218
180
168
308
329
215
177
184
243
229
400
198
400
324
355
335
400
400
400
V.
.5
.5
.4
.7
.5
. 1
.0
.3
.5
.6
.3
.6
.7
.0
.5
.0
.6
.4
.5
.0
.0
.0
Mean
3157.2
232. 1
40.9
116.4
54.8
110.2
92.8
103.3
65.3
12.4
12.7
45.9
15.6
41.6
2.5
4. 1
3.8
2.0
0.3
0.0
0.2
0.3
S.
2837
175
17
63
24
46
71
85
35
5
5
28
9
41
1
4
3
1
0
0
0
0
E. Slopeb
.3
.6
.7
.6
.7
.3
.4
.0
.2 -16. 1
.5
.9 -2.5
.0
.0
.6
.2
. 1
. 1
.8
.3
.0
.2
.3
Mean
20.5
12.5
8.5
6.7
6. 1
5.3
5. 1
3.7
2.9
1.5
1.2
1. 1
0.9
0.8
0.5
0. 1
0. 1
0. 1
0. 1
0.0
0.0
0.0
S.E.
7. 1
6.3
3.2
4.8
2.5
2.8
3. 1
3. 1
1.3
0.7
0.6
0.7
0.5
0.8
0.3
0. 1
0.0
0. 1
0. 1
0.0
0.0
0.0
C.
137
201
150
285
166
212
237
337
185
183
193
260
246
400
268
400
283
394
375
400
400
400
V. Slope
.9
.6
.2
.6
.2
.9
.8
. 1
.2 -0.7
.6
.3
.8
.6
.0
.6
.0
. 1
.4
.6
.0
.0
.0
Densities are expressed in terms of birds per 1000 ha of shoal water habitat «2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-5.
MARYLAND BUFFLEHEAD POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
D e n s i t yc
Percent
Survey area
Lower Chop-tank River
Eastern Bay
Chester River
Manokin, Big - Little Annemessex R.
Little Choptank River
Miles Ri ver
South River - Herring Bay
Patuxent River
Susquehanna Flats
Bayshore, Calvert County
Patapsco River - Aberdeen P.G.
Honga River
Bloodsworth - South Marsh Islands
Magothy - Severn Rivers
Fishing Bay
Wye River
Smith Island
Nanticoke - Wicomico Rivers
Bayshore, Kent Island
Upper' Choptank River
Bayshore, Hooper Island
Northeast - Elk - Bohemia Rivers
Bayshore, Kent County
Sassafras River
Mean
754.
710.
608.
258.
341.
306.
420.
316.
110.
232.
85.
205.
175.
97.
90.
109.
90.
102.
67.
54.
46.
31.
28.
1.
1
0
9
7
3
9
6
4
3
8
2
6
4
8
5
1
1
5
2
7
1
2
1
6
S.E.
197.7
179.4
219.2
57.4
59.0
83.2
223.2
I 1 0 . 9
52.8
80.2
46. 1
67.2
123.5
28.4
26.6
56.3
47.5
42.5
23.7
21.8
25. 1
25.4
19.2
1.6
C.V.
104.8
101.1
144.0
88.8
69.2
108.5
212.3
140.2
191.5
137.8
216.4
130.7
281.5
116.3
117.7
206.3
210.7
165.9
141.0
159.4
218. 1
324.6
273.3
383.9
Mean
57.3
89.3
78.2
18.7
45.4
142. 1
93.8
41.8
13.7
84.4
4.9
29.8
15.3
21.7
14.5
61.5
21. 1
13.9
30.3
26.4
8. 1
6.9
11.5
1.0
S.
15
22
28
4
7
38
49
14
6
29
2
9
10
6
4
31
1 1
5
10
10
4
5
7
0
E. Slopeb
.0 9.4
.6 17.0
. 1
.2
.9
.6
.8
.7
.5
. 1
.7
.7 4.2
.8
.3 2.7
.3
.7
. 1
.8
.7
.5
.4
.6
,9
.9
Mean
8.9
7.7
6.9
6.4
6.3
4.7
4.6
4.4
4.3
4.0
2.5
2.4
2.0
1.7
1.7
1.6
1.6
1.5
1.0
0.8
0.6
0.4
0.2
0.0
S.E.
2. 1
1.6
2. 1
2. 1
1.5
1.4
1.8
1.6
2.7
1.6
2.0
0.6
0.8
0.7
0.7
0.7
1.0
0.5
0.4
0.3
0.2
0.4
0. 1
0.0
C.V.
95.6
83.3
120.9
132.6
93.5
121.6
161.3
146.7
247.3
159.6
325.6
105.6
167.0
156.9
172.3
173.2
239.2
132.9
166. 1
151. 1
156.3
368.6
235. 1
345.9
Slope
1.0
1. 1
-1. 1
Densities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-6. MARYLAND COMMON GOLDENEYE POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Survey area
Lower Choptank River
Eastern Bay
Little Choptank River
Chester River
Bayshore, Kent Island
Miles River
South River - Herring Bay
Honga River
Bayshore, Calvert County
Susquehanna Flats
Bayshore, Hooper Island
Fi shi ng Bay
Manokin, Big - Little Annemessex R.
Wye River
Nanticoke - Wicomico Rivers
Patuxent River
Upper Choptank River
Bloodsworth - South Marsh Islands
Magothy - Severn Rivers
Bayshore, Kent County
Northeast - Elk - Bohemia Rivers
Patapsco River - Aberdeen P.G.
Smith Island
Sassafras River
N u
Mean
4086.5
2961.9
1447.8
1583.5
1052.0
1015.9
541.9
667.2
348.4
324.7
483.9
409.8
453. 1
460.9
366.9
436.6
252.6
295.9
204.4
150.6
100.6
63.8
81.2
40.8
m b e r
S.E.
725.2
541. 1
238.0
401.4
239.7
223.6
263. 1
143.0
115.5
133.4
103.5
65.3
120.8
107.5
116.8
150.0
72.4
110.6
77.7
32.9
40.3
24.0
40.0
31.3
C.V.
71.0
73. 1
65.8
101.4
91. 1
88.0
194.2
85.8
132.6
164.3
85.5
63.7
106.6
93.3
127.4
137.4
114.6
149.6
152. 1
87.4
160.2
150.6
197.0
307.0
D e r
Mean
310.5
372.4
192.7
203.2
475.2
470.5
120.8
96.7
126.3
40.2
85.4
65.6
32.8
259.7
49.8
57.7
121.9
25.8
45.4
61.6
22.2
3.7
19.0
24.7
» s i
S.
55
68
31
51
108
103
58
20
41
16
18
10
8
60
15
19
34
9
17
13
8
1
9
19
t y a
E. Slope15
. 1
.0
.7
.5
.3
.6
.7
.7
.9 21.9
.5
.3
.4
.7
.6
.9
.8
.9
.7
.3
.5
.9
.4
.4
.0
F
Mean
19.2
14.0
7.3
7.2
5.4
4.5
3.2
3.2
2.8
2.5
2.3
2.3
2.2
2. 1
2.0
1.8
1.3
1.3
1.2
1. 1
0.6
0.3
0.3
0.2
» e
S.
2
1
0
1
1
0
1
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
r c
E.
.9
.7
.9
.4
. 1
.9
.9
.6
.4
.3
.5
.4
.5
.5
.5
.5
.3
.5
.4
.4
.2
. 1
. 1
.2
e n t
C.V.
60.8
48.6
51.9
78.2
82.0
78.3
238.5
74.5
198.8
203.3
82.3
63.9
88.6
101.1
107.8
109.7
106.6
161.5
127.3
150.4
162.9
125.0
184.6
315.7
Slope
0.6
-0.3
aDensities are expressed in terms of birds per 1000 ha of shoal water habitat «2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-7. MARYLAND CANVASBACK POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
D e n s i t y£
Percent
Survey area
Lower Choptank Rive'r
Bayshore, Calvert County
Patuxent River
South River - Herring Bay
Nanticoke - Wicomico Rivers
Chester River
Eastern Bay '
Little Choptank River
Bayshore, Kent Island
Bayshore, Kent County
Patapsco River - Aberdeen P.G.
Magothy - Severn Rivers
Uye River
Fi shi ng Bay
Miles Ri ver
Upper Choptank River
Manokin, Big - Little Annemessex R.
Honga River
Susquehanna Flats
Sassafras River
Bayshore, Hooper Island
Bloodsworth - South Marsh Islands
Smith Island
Northeast - Elk - Bohemia Rivers
Mean
7229.9
6655.6
6043.4
4134.8
3662.8
3127.6
2711.2
2892.5
4473. 1
2450.6
1595. 1
2444. 1
2055.3
1315.5
980. 1
522.5
447.0
287.5
295.3
178. 1
253. 1
193.8
78. 1
16.4
S.
1237
2^01
1953
789
1835
832
613
353
4041
1 183
847
892
716
586
314
166
187
143
170
123
170
174
37
12
E.
.4
.4
. 1
.2
.2
.2
.4
.4
.7
.4
.5
.3
.9
.8
.3
.4
. 1
.9
.0
.5
.4
.8
.4
.4
C.
68
174
129
76
200
106
90
1 18
361
193
212
146
139
178
128
127
167
200
230
277
269
360
191
303
V.
.5
.4
.3
.4
.4
.4
.5
.0
.4
.2
.5
.0
.5
.4
.3
.4
.4
.3
.3
.3
.2
.8
.2
.7
Mean
549.4
2413.2
798.8
922. 1
497.3
401.4
340.9
384.9
2020.4
1002.7
92.6
542.9
1157.9
210.6
453.9
252.0
32.4
41.7
36.6
108. 1
44.7
16.9
18.3
3.6
S.
94
1052
258
176
249
106
77
113
1825
484
49
198
403
93
145
80
13
20
21
74
30
15
8
2
E. Slopeb
.0
.0
. 1
.0
. 1
.8
. 1
.6
.5
.2
.2
.2
.9
.9
.6
.3 -33.7
.5
.9
. 1
.9
. 1
.3
.8
.7
Mean
8.4
7.9
6.5
5.5
3.7
3.6
3.4
3.2
3.0
2.7
2.4
2.4
2.2
1.6
1.2
0.6
0.6
0.4
0.3
0.3
0.3
0.2
0. 1
0.0
S.E.
1.2
3. 1
1.9
1.3
1.7
1 .0
0.9
0.9
2.3
1 . 1
1.5
0.7
0.7
0.8
0.4
0.2
0.3
0.2
0.2
0.2
0.2
0.2
0.0
0.0
C.V. Slope
57.8
157. 1
1 16.9
96.4
179.8
107.5
102.4
107.8
312.6
161.0
246.0
121.6
128.2
195.7
120.3
122. 1
212.7
233.7
223.4
321.9
226.5
375.8
192.8
288.9
Densities are expressed in terms of birds per 1000 ha of shoal water habitat «2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-8.
MARYLAND SCAUP POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Density3 Percent
ON
Survey area
Patuxent River
Bayshore, Calvert County
Bayshore, Kent Island
South River - Herring Bay
Magothy - Severn Rivers
Honga River
Lower Choptank River
Fishing Bay
Patapsco River - Aberdeen P.O.
Bayshore, Kent County
Manokin, Big - Little Annemessex R.
Chester River
Little Choptank River
Nanticoke - Wicotnico Rivers
Bayshore, Hooper Island
Eastern Bay
Bloodsworth - South Marsh Islands
Smith Island
Wye River
Upper Choptank River
Miles River
Susquehanna Flats
Northeast - Elk - Bohemia Rivers
Sassafras River
Mean
5640.6
3212.5
993.8
1620.0
671.6
1112.5
843.4
865.6
899. 1
395.9
503. 1
707.0
673.4
443.8
326.6
333.8
335. 1
289. 1
263.4
245.3
73.4
106.2
7.8
2.8
S.E.
2387.0
1319.9
654.4
808.2
368. 1
804.4
258.0
521.4
326.2
195.6
176.2
337.4
406. 1
194.5
324.9
142.4
245.0
261.4
166.5
185.6
46.8
68.0
6.3
1.9
C.V.
169.3
164.4
263.4
199.6
219.2
289.2
122.4
240.9
145. 1
197.6
140. 1
190.9
241.2
175.3
398.0
170.7
292.4
361.8
252.7
302.6
254.9
256.0
324.6
275.2
Mean
745.5
1164.8
448.8
361.3
149.2
161.3
64. 1
138.6
52.2
162.0
36.4
90.7
89.6
60.2
57.6
42.0
29.3
67.8
148.4
118.3
34.0
13.2
1.7
1.7
S.
315
478
295
180
81
116
19
83
18
80
12
43
54
26
57
17
21
61
93
89
21
8
1
1
E. Slope^ Mean
.5
.6
.6
.2
.8
.6
.6
.5
.9
.0
.8
.3
.0
.4
.4
.9
.4
.3
.8
.5
.7
.4
.4
.2
9
6
6
4
3
2
1
1
0
0
0
0
0
0
0
0
0
.7
.4
.3
.8
.4
.8
.9
.9
.7
.7
.5
.3
.2
. 1
.0
.9
.6
.5
.4
:4
.2
. 1
.0
.0
S.
3
2
5
2
2
2
0
1
0
1
0
0
0
0
1
0
0
0
0
0
0
0
0
0
E.
.5
.9
.2
.9
.4
.3
.7
.2
.6
.0
.7
.6
.5
.5
.0
.5
.4
.5
.2
.3
. 1
. 1
.0
.0
C.V. Slope
143.4
180.7
330.3
241.6
281.5
328.6
146.5
254.0
135.8
232. 1
188. 1
187.2
181.8
181.5
397.5
202.5
262.7
358.7
214.5
269.0
291.8
243.5
311.2
273.3
aDensities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-9. MARYLAND REDHEAD POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Density3 Percent
Survey area
Lower Choptank River
Bayshore, Calvert County
Honga River
Patuxent River
Little Choptank River
Susquehanna Flats
Eastern Bay
Chester Ri ver .
Bayshore, Hooper Island
Sassafras River
Magothy - Severn Rivers
South River - Herring Bay
Bayshore, Kent Island
F i shi ng Bay
Miles River
Wye River
Upper Choptank River
Nanticoke - Uicomico Rivers
Bayshore, Kent County
Patapsco River - Aberdeen P.G.
Bloodsworth - South Marsh Islands
Smith Island
Manokin, Big - Little Annemessex R.
Mean
5656.6
3989. 1
2984.4
2106.6
2674.1
1341.2
1712.5
802.8
1034.4
89. 1
726.6
887.5
1668.8
951.6
464.1
450.0
575.0
753. 1
170.3
151.2
181.2
87.5
12.5
S.
2486
1974
1419
1033
845
1318
917
408
445
64
425
527
1557
609
291
197
451
560
102
101
156
60
12
E.
.7
.3
.6
.8
.6
.7
.6
.9
.8
.2
.7
.6
.2
.7
.9
.7
.8
.0
.7
.0
.6
.5
.5
C.V.
175.8
198.0
190.3
196.3
126.5
393.3
214.3
203.7
172.4
288.3
234.4
237.8
373.3
256.3
251.6
175.8
314.3
297.4
241.2
267.2
345.6
276.4
400.0
Mean
429.9
1446.4
432.8
278.4
355.8
166. 1
215.3
103.0 £
182.6 '
54.0
161.4
197.9
753.7
152.3
214.9
253.5
277.4-
102.2
69.7
8.8
15.8
20.5
0.9
S.E. Slopeb
189.0 -81.9
715.8
205.9
136.6
112.5
163.3
115.4
52.5 -24.3
78.7
38.9
94.6
117.7
703.3
97.6
135.2
111.4
217.9
76.0
42.0
5.9
13.7
14.2
0.9
Mean
12.7
10.4
8.6
8. 1
6.4
4.5
3.5
3.0
2.8
2.5
2.3
2.0
1.7
1.7
1.6
1.3
1.0
0.9
0.8
0.4
0.3
0.2
0.0
S.E.
3.4
4.9
4.7
5.5
1..8
4.4
1.2
1.4
1.5
2.4
1.7
1.2
1.3
1.2
1. 1
0.7
0.4
0.5
0.4
0.2
0.3
0. 1
0.0
C.
108
188
217
271
1 1 1
395
138
189
216
389
290
239
311
294
288
198
182
219
210
258
373
277
400
V.
.2
.0
.9
.8
.5
.2
.8
.5
.3
.7
.6
.9
.3
.0
.0
.0
.6
.3
,8
.5
.2
.0
.0
Slope
-0.2
aDensities are expressed in terms of birds per 100(1 ha of shoal Mater habitat «2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
oo
APPENDIX TABLE F-10. MARYLAND AMERICAN WIGEON POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Density3 Percent
Survey area
Eastern Bay
Lower Choptank River
Chester River
Honga River
Bayshore, Hooper Island
Little Choptank River
Smith Island
Patapsco River - Aberdeen P.G.
Wye River
Bloodsworth - South Marsh Islands
Bayshore, Kent Island
South River - Herring Bay
Susquchanna Flats
Manokin, Big - Little Annemessex R.
Patuxent River
Miles River
Magothy - Severn Rivers
Nanticoke - Wicomico Rivers
Sassafras River
Upper Choptank River
Bayshore, Kent County
Fi shi ng Bay
Northeast - Elk - Bohemia Rivers
Mean
2338.5
2324.7
2065.8
532.3
524.6
605.4
476.6
483.4
865.4
345.3
210.8
230.3
226.2
147.2
141.9
142.6
71.6
99.4
148.4
84.2
45.3
62.2
16.9
S.
737
526
637
218
170
177
226
359
620
110
179
103
109
42
46
67
34
49
68
40
18
28
12
E.
.4
.3
.9
.7
.8
. 1
.6
.4
.4
.4
.8
.6
.6
.3
.3
.4
.5
.8
.6
.2
.0
.4
.6
C.V.
126.1
90.6
123.5
164.4
130.2
117.0
190.2
297.4
286.8
127.9
341.3
179.8
193.7
115. 1
130.6
189.0
193. 1
200.5
185.0
191.0
158.9
182.9
298.6
Mean
294.0
176.7
265.2
77.2
92.6
80.6
111.7
28. 1
487.5
30.2
95.2
51.4
28.0
10.7
18.8
66.0
15.9
13.5
90. 1
40.6
18.5 -
10.0
3.7
S.E. . Slopeb
92.7
40.0 -17.6
81.9 -40.4
31.7
30. 1
23.6
53.1
20.9
349.5
9.6
81.2
23. 1
13.6
3. 1
6. 1
31.2
7.7
6.8
41.6 -21.1
19.4
7.4
4.6
2.8
Mean
13.
13.
12.
6.
6.
4.
3.
2.
2.
2.
1.
1.
1 .
1 .
1.
0.
0.
0.
0.
0.
0.
0.
0.
3
1
3
6
0
0
8
9
7
6
8
8
6
3
0
9
8
7
6
5
3
3
1
S.E.
2.7
1.4
3.2
4.7
2.3
.2
.5
.7
.5
.2
.6
0.9
0.9
0.3
0.4
0.5
0.5
0.3
0.2
0.3
0. 1
0. 1
0.0
C.V.
81. 1
41.7
104.5
285.6
152.0
115.7
153.0
231.6
218.4
175.7
353.5
209.0
221.2
105.3
154.6
197.7
253.0
181.2
146.5
205.9
176.0
163.3
235. 1
Slope
-1.3
1.0
-0.7
0.2
-0. 1
Densities are expressed in terms of birds per 1000 ha of shoal water habitat «2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-11. MARYLAND BLACK DUCK POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
D e n s i t y a
Percent
Survey area
Chester River
Eastern Bay
Lower Chop-tank River
Wye River
Sassafras River
Honga R i ver
Nanticoke - Wicomico Rivers
Bayshore, Hooper Island
Miles Ri ver
Manokin, Big - Little Annemessex R.
Smith Island
Little Choptank River
Bloodsworth - South Marsh Islands
Bayshore, Kent Island
Fishing Bay
Bayshore, Kent County
Upper Choptank River
Patapsco River - Aberdeen P.G.
Patuxent River
Susquehanna Flats
Northeast - Elk - Bohemia Rivers
South River - Herring Bay
Magothy - Severn Rivers
Bayshore, Calvert County
Mean
17466.
7666.
6405.
3124.
2147.
2223.
2072.
2057.
1408.
1448.
1370.
1258.
1558.
1135.
985.
976.
815.
665.
495.
372.
483.
222.
164.
40.
2
8
0
2
0
4
9
4
1
1
9
4 .
4
4
7
3
7
8
9
5
4
4
0
9
S.E.
3266.0
1541.9
854.3
763.8
922.9
627. 1
357.5
491.2
225.9
344.3
326.7
214.7
442.3
420.8
234.4
210. 1
173. 1
352.9
131.5
128.9
194.7
57.0
50.2
25.4
C.V.
74.8
80.4
53.4
97.8
172.0
112.8
69.0
95.5
64.2
95. 1
95.3
68.3
113.5
148.2
95. 1
86. 1
84.9
212. 1
106. 1
138.4
16 1. 1
102.4
122.4
248. 1
Mean
2241.8
964.0
486.7
1760. 1
1302.8
322.4
281.4
363.2
652.2
104.8
321.4
167.5
136.2
512.8
157.8
399.5
393.5
38.6
65.5
46. 1
106.8
49.6
36.4
14.8
s:
419
193
64
430
560
90
48
86
104
24
76
28
38
190
37
86
83
20
17
16
43
12
1 1
9
E. Slope13
.2 -208. 1
.9
.9
.3
.0
.9
.5
.7
.6
.9
.6
.6
.6
.0 -87.5
.5
.0
.5 -36.6
.5
.4
.0 -6.8
.0
.7
. 1 4.9
.2
Mean
23.6
11.5
9.7
4.4
3.3
3.3
3.2
3.0
2.3
2.3
2.2
2. 1
2. 1
1.9
1.5
1.4
1.2
0.7
0.7
0.6
0.6
0.4
0.3
0. 1
S.E.
2.2
2.0
1.2
0.9
1.5
1.0
0.5
0.6
0.4
0.6
0.5
0.4
0.6
0.8
0.4
0.3
0.2
0.3
0. 1
0.2
0.2
0. 1
0. 1
0.0
C.V.
36.8
71.3
51.2
80.2
178.7
1 16.7
64.9
77.0
74.2
105.6
97.0
81.5
111.6
157. 1
102.7
75.8
66.7
168.0
82.2
169.5
105.7
103.4
127.5
234.4
Slope
-0.9
0.2
-0.3
Densities are expressed in terms of birds tier 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rat'es of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-12. MARYLAND MALLARD POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
Den s i t y«
Percent
Survey area
Chester River
Sassafras River
Eastern Bay
Lower Choptank River
Wye Ri ver
Nanticoke - Ulicomrco Rivers
Bayshore, Kent Island
Bayshore, Kent County
Bayshore, Hooper Island
Miles River
Honga River
Smith Island
Northeast - Elk - Bohemia Rivers
Patuxent River
Little Choptank River
Bloodsworth - South Marsh Islands
Upper Choptank River
Patapsco River - Aberdeen P.G.
Susquehanna Flats
Magothy - Severn Rivers
Manokin, Big - Little Annemessex R.
South River - Herring Bay
Fishing Bay
Bayshore, Calvert County
Mean
14504.2
2777.9
2184. 1
1848.8
2139.8
1351.4
554.3
482.6
440.9
333.2
441.6
235. 1
318.9
286.9
208.8
240.3
163.4
227. 1
122.8
128. 1
210. 1
89. 1
84.4
12.5
S.E.
3247.9
1191.6
605.0
396.2
899.8
437.2
231.2
125.8
145.2
94.0
215.9
45.7
162. 1
81.9
41.9
73. 1
38. 1
94.3
40.3
55.5
61.7
51.4
40.7
12.5
C.V.
89.6
171.6
110.8
85.7
168.2
129.4
166.8
104.3
131.8
112.8
195.6
77.7
203.4
114.2
80.3
121.7
93.3
166.2
131.3
173.2
1 17.4
230.8
192.9
400.0
Mean
1861
1685
274
140
1205
183
250
197
77
154
64
55
70
37
. 27
21
78
13
15
28
15
19
13
4
.7
.6
.6
.5
.5
.5
.4
.5
.8
.3
.0
. 1
.4
.9
.8
.0
.8
.2
.2
.5
.2
.9
.5
.5
S.
416
723
76
30
506
59
104
51
25
43
31
10
35
10
5
6
18
5
5
12
4
1 1
6
4
E. Slopeb
.9
.0
. 1
. 1
.9
.3
.4 -45.8
.5
.6
.5 18.5
.3
.7
.8
.8
.6
.4
.4
.5
.0
.3
.5
.5
.5
.5
Mean
33.9
7.7
6.3
6.2
5.4
4.5
2.2
1.7
1. 1
1.0
0.9
0.8
0.7
0.7
0.7
0.7
0.6
0.5
0.5
0.5
0.5
0.2
0.2
0.0
S.E.
3.8
2.4
1.6
1.4
2. 1
1.6
0.9
0.5
0.4
0.2
0.4
0.2
0.2
0.2
0.2
0.3
0.2
0.2
0.2
0.2
0. 1
0. 1
0. 1
0.0
C.V.
45.2
123.4
104.6
92.8
156.0
146.0
160.5
124.5
129.2
94.2
191.3
114.3
122.6
101.3
103.6
159.5
104.4
138. 1
170.4
178.0
121.0
181.2
198.0
400.0
Slope
0.8
-0.4
0. 1
Densities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE F-13.
MARYLAND PINTAIL POPULATIONS, DENSITIES, AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 16 YEAR PERIOD 1956-71
Number
D e n s i t yc
Percent
Survey area
Smith Island
Chester Ri ver
Eastern Bay
Sassafras River
Bayshore, Hooper Island
Honga River
Lower Choptank River
Bloodsworth - South Marsh Islands
Manokin, Big - Little Annemessex R.
Bayshore, Kent Island
Bayshore, Kent County
Nanticoke - Wicomico Rivers
Little Choptank River
Wye Ri ver
Miles Ri ver
Northeast - Elk - Bohemia Rivers
Bayshore, Calvert County
Upper Choptank River
Fi shi ng Bay
Patapsco River - Aberdeen P.O.
Patuxent River
Mean
2527.
3083.
1076.
146.
490.
291.
670.
730.
350.
222.
301.
159.
91.
161.
35.
15.
14.
15.
40.
1.
7.
8
2
8
9
6
9.
8
3
6
8
6
4
4
9
6
6
1
6
9
1
8
S.E.
1223.0
1196.8
443.5
105.4
192.3
116.9
395.7
279.4
223.7
113.5
220.7
121.9
44.2
123.6
19.6
12.5
12.5
10.9
21.9
1. 1
6.3
C.V.
193.5
155.3
164.8
287. 1
156.7
160.2
236.0
153. 1
255.2
203.8
292.7
305.9
193.2
305.3
220.2
319.3
355.4
279.4
213.7
400.0
324.6
Mean
592.7
395.7
135.4
89. 1
86.6
42.3
51.0
63.8
25.4
100.6
123.4
21.6
12.2
91.2
16.5
3.4
5. 1
7.5
6.6
0. 1
1.0
S.
286
153
55
64
33
17
30
24
16
51
90
16
5
69
9
2
4
5
3
0
0
E. Slopeb
.7
.6 -84.4
.8
.0
.9
.0
.1 -14.1
.4
.2
.3
.3
.5
.9
.6
. 1
.8
.5
.3 -2.4
.5 -1.5
. 1
.8
Mean
17.9
16.7
11.5
5.6
5.2
5. 1
4.9
4.6
3. 1
2.8
2.5
1.5
1.4
0.8
0.7
0.2
0.2
0. 1
0. 1
0.0
0.0
S.
5
5
4
5
1
3
2
1
2
1
1
1
0
0
0
0
0
0
0
0
0
E.
.7
.8
.4
. 1
.8
. 1
.4
.7
. 1
.3
.8
.2
.9
.3
.4
.2
. 1
. 1
. 1
.0
.0
C.V. Slope
126.4
138.0
153.9
366.6
142. 1
242.4
196.0
145.4
271.5
180.3
285.0
319.8
265.6
172.6
190.9
260.3
277.4
314.5
176.7
400.0
338.5
aDensities are expressed in terms of birds per 1000 ha of shoal water habitat (<2.44 m at mlw).
"Area populations (density and percent) were regressed against years. Slopes, which estimate rates of change per
year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-1. VIRGINIA WHISTLING SWAN POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
Smith Pt. to Windmill Pt.
Rappahannock River (Lower)
Silver Beach to Saxis
Rappahannock River (Upper)
Mobjack Bay and Piankatank River
Newport News to York River
Fisherman's Island to Silver Beach
York River
James River (Middle)
James River (Hog Island Refuge)
Mean
87
11
5
0
1 1
9
4
2
1
0
.7
.9
.9
.5
.4
. 1
. 1
.3
.5
.5
N u
S.
63
7
5
0
9
9
2
2
1
0
m b e r
E.
.9
.2
.9
.5
. 1
. 1
.8
.3
. 1
.5
C.
241
200
331
331
267
331
224
331
226
331
V. Slope3 Mean
.7
.7
.7
.7
.0
.7
.2
.7
.7
.7
2
1
0
0
0
0
0
0
0
0
.4
.3
.5
.5
.3
.3
.2
.0
-0
.0
Per
S.E.
1.4
0.7
0.5
0.5
0.3
0.3
0.2
0.0
0.0
0.0
c e n
C.
181
175
316
316
271
316
248
316
268
316
t
V. Slope
.5 0.9
.8
.2
.2
.4 0.2
.2
.5
.2
.6
.2
aArea populations (number and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-2.
VIRGINIA CANADA GOOSE POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
James River (Presquile NWR)
Pamunkey River
Fisherman's Island to Silver Beach
James River (Hog Island Refuge)
Rappahannock River (Upper)
James River (Upper)
Silver Beach to Saxis
James River (Lower)
Rappahannock River (Lower)
James River (Middle)
Smith Pt. to Windmill Pt.
Mattaponi River
York River
Mob jack Bay and Piankatank River
Newport News to York River
Chickahominy River
Mean
8972
6144
7835
3439
3311
1920
895
759
755
345
560
196
85
71
1 1
6
.3
. 1
.5
. 1
.4
.9
.9
.4
.7
.9
.5
.8
.0
.4
.8
.4
N u
S.
869
558
4843
442
888
375
280
306
324
150
435
42
30
53
9
5
m b e r
E.
.7
.7
.0
. 1
. 1
.4
.3
.4
.0
.9
.6
.6
. 1
.8
.2
.4
C.
32
30
205
42
88
64
103
133
142
144
257
71
117
249
258
283
V.
. 1
.2
.0
.6
.9
.8
.8
.8
.2
.6
.8
.7
.5
.8
.9
.5
Slope3- Mean
580.8 22
15
10
8
764.3 7
4
2
1
1
0
0
-26.5 0
20.9 0
0
0
0
.0
.2
.7
.6
.6
.7
. 1
.4
.4
.8
.7
.6
.2
. 1
.0
.0
Percent
S.E.
2.4
1.7
4.3
1.4
2.0
1. 1
0.7
0.4
0.4
0.4
0.3
0.1
0.0
0.0
0.0
0.0
C.V.
35.5
37. 1
133.3
51.9
87.0
79.4
116.0
84. 1
98.8
160.0
167.3
89. 1
97.7
190. 1
285.0
297.9
Slope
-1. 1
1.6
aArea populations (number and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-3.
VIRGINIA RUDDY DUCK POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
Rappahannock River (Lower)
York River
Newport News to York River
James River (Lower)
James River (Middle)
Rappahannock River (Upper)
Mobjack Bay and Piankatank River
Smith Pt. to Windmill Pt.
James River (Hog Island Refuge)
James River (Upper)
Pamunkey River
James River (Presquile NWR)
Silver Beach to Saxis
Mean
8348
2640
1619
1216
633
338
176
66
11
80
4
2
4
.6
.9
. 1
.2
.2
.2
.4
.8
.4
.0
.5
.3
. 1
N u
S.
1821
1054
746
743
406
287
45
35
9
46
4
1
4
m b
E.
.0
. 1
.2
.8
.3
.2
-0
.8
. 1
.3
.5
.6
. 1
e r
C.
72
132
152
202
212
281
84
177
267
191
331
227
331
V. Slope3 Mean
.3
.4
.9
.8
.8
.7
.6
.5
.0
.9
.7
.9
.7
56
15
9
4
3
2
2
1
0
0
0
0
0
.9
.4
.4
.7
.3
.4
.4
.7
.5
.3
.2
. 1
.0
Per
S.E.
7.0
5.5
4.0
2.3
2. 1
1.3
0.8
1.3
0.5
0.2
0.2
0. 1
0.0
c e n
C.
41
118
140
161
211
172
1 13
242
323
180
331
315
331
t
V. Slope
.0
.3
.2
.5
. 1
.6
.6
.5
. 1
.0
.7
.9
.7
aArea populations (number and percent) were regressed against years.
per year, are shown if significant (0.05 level).
Slopes, which estimate rates of change
-------
APPENDIX TABLE G-5. VIRGINIA BUFFLEHEAD POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
Rappahannock River (Lower)
Mobjack Bay and Piankatank River
Newport News -to York River
York River
Smith Pt. to Windmill Pt.
James River (Lower)
Fisherman's Island to Silver Beach
Silver Beach to Saxis
Rappahannock River (Upper)
James River (Middle)
Pamunkey River
Mattaponi River
Mean
698.
370.
265.
293.
146.
69.
176.
117.
55.
54.
3.
2.
2
5
0
6
4
5
4
7
5
5
6
3
N u
S.
265
120
119
98
46
23
127
80
37
21
2
2
m b
E.
.6
.8
.3
.5
.3
.9
.8
.5
. 1
.0
.5
.3
e r
C.
126
108
142
1 11
104
114
240
226
221
128
230
331
V. Slope3 Mean
.2
.2
.4
.2
.9
.3
.4
.7
.8
•0
.8
.7
20
20
15
13
6
6
2
2
2
1
0
0
.8
. 1
.8
.3
.3
.0
.9
.3
. 1
.9
. 1
. 1
Per
S.E.
6.6
5.6
5.4
3.2
1.9
3.0
2.0
1.3
1.3
0.8
0. 1
0. 1
c e n
C.
105
93
107
78
98
169
226
178
211
144
222
331
t
V. Slope
.7
.0
.9
.6
.5
.8
.8
.0
. 1
.6
.5
.7
Area populations (number and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-6.
VIRGINIA CANVASBACK POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Number
Survey area
Rappahannock River (Lower)
James River (Lower)
York River
James River (Middle)
Rappahannock River (Upper)
Smith Pt. to Windmill Pt.
Newport News to York River
Mobjack Bay and Piankatank River
James River (Upper)
Fisherman's Island to Silver Beach
Pamunkey River
Mattaponi River
Silver Beach to Saxis
James River (Hog Island Refuge)
Mean
2248
1458
1517
1501
255
786
502
219
1<*1
50
12
4
2
0
S.E.
.6
.8
.2
.4
.9
.4
.3
. 1
.8
.0
.7
.5
.3
.9
628.
483.
445.
508.
139.
781.
333.
208.
135.
27.
9.
4.
2.
0.
4
5
0
5
1
4
4
3
9
8
4
5
3
9
C.
92
109
97
112
180
329
220
315
317
184
246
331
331
331
V . Slope3 Mean
.7
.9
.3
.3
.3
.6
.2
.3
.7
.4
.2
.7
.7
.7
30
16
15
13
4
3
3
1
0
0
0
0
0
0
.2
.7
.7
.3
.9
.5
.3
.2
.8
.3
. 1
.0
.0
.0
Per
S.E.
8. 1
6.4
3. 1
3.9
2.3
3.4
1.6
0.9
0.8
0.2
0. 1
0.0
0.0
0.0
c e n
t
C.V. Slope
88.
128.
66.
97.
156.
325.
162.
249.
318.
176.
227.
331.
331.
331.
5
2
2 -2.5
5
4
0
0
6
1
4
0
7
7
7
aArea populations (number and percent) were regressed against years.
per year, are shown if significant (0.05 level).
Slopes, which estimate rates of change
-------
APPENDIX TABLE G-7. VIRGINIA AMERICAN WIGEON POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
oo
Survey area
James River (Lower)
Silver Beach to Saxis
Mobjack Bay and Piankatank River
Fisherman's Island to Silver Beach
Smith Pt. to Windmill Pt.
York River
Newport News to York River
Pamunkey River
James River (Presquile NUIR)
Rappahannock River (Lower)
James River (Middle)
James- River (Upper)
James River (Hog Island Refuge)
Mean
561
HO
34
109
23
33
22
20
14
10
11
10
9
. 1
.0
. 1
. 1
.2
.6
.3
.9
. 1
.0
.7
.9
. 1
N u
S.
166
84
17
56
9
14
10
20
7
4
6
10
9
m b
E.
.7
.0
.9
.3
.8
.0
.6
.9
.7
.2
.3
.9
. 1
e r
C.
98
199
174
171
140
137
157
331
182
139
177
331
331
V. Slopea Mean
.6
.0
.5
.3
.5
.9
.9
.7
.2
.6
.4
.7.
.7
21
5
4
3
2
1
1
0
0
0
0
0
.0
.4
.7
.9
S3
.6
.3
.3
.9
.6
.4
.2
.2
Per
S.E.
8.0
3.4
4.0
2.3
2.0
2.0
0.6
1.3
0.6
0.5
0.2
0.2
0.2
c e n
C.
125
211
283
194
200
255
149
331
220
264
182
331
331
t
V. Slope
.7
.8
.2
.4
.8
.8
.2
.7
. 1
.2
.8
.7
.7
Area populations (number and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-8. VIRGINIA BLACK DUCK POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
Pamunkey River
Chi ckahomi ny River
James River (Presquile NWR)
Rappahannock River (Upper)
James River (Lower)
Fisherman's Island to Silver Beach
Silver Beach to Saxis
James River (Hog Island Refuge)
York River
James River (Upper)
Rappahannock River (Lower)
Mattaponi River
Mobjack Bay and Piankatank River
Smith Pt. to Windmill Pt.
Newport News to York River
James River (Middle)
Mean
1801.8
1448.3
1262.3
1275.0
1170. 1
879. 1
651.8
418.2
368.6
410.0
280.0
238.2
162.5
173.6
165.5
93.5
Numb
S.E.
438. 1
386.5
260.6
294.4
595.6
302.3
151.7
105.2
88.0
89.5
81.8
51.5
77.6
123.2
52.3
28.0
e r
C.V. Slope3
80.6 -290.1
88.5
68.5
76.6 -266.2
168.8 -385.7
114.0
77.2
83.4
79.2
72.4
97.0
71.7
158.4
235.2
104.8
99.4
Mean
10.3
8.7
7.4
6.6
5.5
4.4
3.5
2.8
2.7
2.4
2.4
1.6
1. 1
1.0
1.0
0.6
Peri
S.E.
1.7
2.7
1. 1
1. 1
2.2
1.4
0.8
0.8
0.9
0.4
0.9
0.5
0.5
0.8
0.2
0.2
cent
C.V.
55.9
103.3
48.8
55.2
133.0
102. 1
77.0
94.4
111.9
59.8
127. 1
94.8
150.9
246.2
80.6
100.4
Slope
-0.9
-1.4
0.7
aArea populations (dumber and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
-------
APPENDIX TABLE G-9.
VIRGINIA MALLARD POPULATIONS AND PERCENT DISTRIBUTIONS BY SURVEY AREA
DURING THE 11 YEAR PERIOD 1961-71
Survey area
Pamunkey River
James River (Presquile NWR)
Chi ckahomi ny River
Rappahannock River (Upper)
James River (Lower)
James River (Upper)
James River (Hog Island Refuge)
York River
(_i Fisherman's Island to Silver Beach
00
Mattaponi River
Rappahannock River (Lower)
Silver Beach to Saxis
Smith Pt. to Windmill Pt.
James River Wfiddle)
Newport News to York River
Mobjack Bay and Piankatank River
Mean
1537.
1295.
1063.
570.
386-,
327.
243.
135.
161.
122.
89.
51.
34.
51.
31.
4.
7
9
8
9
3
3
2
5
4
3
5
8
1
4
4
1
N u
S.
499
302
215
187
142
70
115
*2
63
37
24
39
26
23
11
2
m b
E.
.7
.2
.9
. 1
.8
.0
.6
.3
.6
.6
.6
.6
.8
.7
.3
.8
e r
C.
107
77
67
108
122
70
157
103
130
102
91
253
260
152
119
224
V. . Slope3
.8
.4
.3
.7 -151.0
.6
.9
.7
.5 '
.7
.0
.2 16.8
.2
.3
.8
.5
.2
Mean
17. 1
15.3
13.2
6.4
4.7
4.4
2.3
2.0
1.7
1.7
1.5
0.7
0.7
0.6
0.4
0. 1
P e
S.
3.
2.
2.
1.
1.
1.
0.
0.
•o.
0.
0.
0.
0.
0.
0.
0.
i r i
E.
6
5
2
9
1
0
8
7
6
6
5
5
6
3
1
0
cent
C.V.
69.5
53.4
56.3
97.4
79.3
77.2
118.8
119.2
112.8
107.9
109.6
251.3
292.2
171.8
112.3
224.8
Slope
-1.4
0.4
aArea populations (number and percent) were regressed against years. Slopes, which estimate rates of change
per year, are shown if significant (0.05 level).
------- |