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The 1967 Die-Off in Lake MicSiigan
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P A Report by the Federal Water Pollution Control Administration
Great Lakes Region
July 25, 1967
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ENVIRONMENTAL PUTSCH CK AGENCY
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TABLE OF CONTENTS
Q Page
Introduction 1
Special Water Quality Survey 6
^ Envi.ronmental Aspects of the Problem- 7
Background of the Problem 13
Origin of the Alewife Population Explosion 17
A Theories on the Alewife Die-Off 26
Extent of the Alewife Die-Off in the Great Lakes 30
Interference to Water Uses by the Alewife Die-Off 31
Research and Studies on the Alewife Problem 3k
Disposal and Control Methods on the Alewife Problem 35
Congressional Concern Over the Alewife Problem- 39
Conclusions-- 1*3
Appendix- ^6
List of References Vf
Special FWPCA Lake Michigan Water Quality Survey,
June-July 196?
References
News Clippings
HOT FOR HJBLICATICa
O
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*~^ INTROHJCTION
On June 15, while on a flight to investigate sources of pollution
in Lake Michigan, an official of the Great Lakes Region of the Federal
Water Pollution Control Afiminictrution spotted long white streaks in
*
t the water. The Navy Hydroplane in which he was riding dipped lower.
The streaks were windrows of dead alewives, belly-up. The wind was
blowing the dead and dying fish toward the Michigan side of the lake.
The official observed one great shimmering band of alewives stretching
for ij-0 miles between Muskegon and South Haven, Michigan. On June 17,
an article in the Chicago Sun-Times mentioned the dead fish and how they
^ had. become an annual pollution problem by littering beaches and producing
a noxious stench. Over the weekend, June 17-18, however, the wind shifted,
blowing from east to west. By Monday, June 19, Chicago's 30 miles of
D
w shoreline was clogged with a silvery carpet of alewive carcasses. The
following day, Tuesday, June 20, the dead fish continued to pile up in
incredible numbers. The great alewife invasion of 1967 was on. Previous
die-offs pale in comparison. None of the Great Lakes had ever experienced
fish deaths of such a continuing magnitude before. Newspapers, which pre-
viously had devoted only a few paragraphs to the annual event, now had
comprehensive front-page stories. (See Appendix)
Theories as to what caused the massive kill proliferated, as the fish
stacked up on beaches in Michigan, Indiana, Illinois and parts of Wisconsin,
_ posing a giant and unprecedented disposal problem.
The IWPCA, Great Lakes Region, had investigators conduct a special
water quality survey, sampling the waters in the southern basin of the lake
from Milwaukee, Wisconsin, to Grand Haven, Michigan. Tests were conducted
-^^ ininri-
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,x to determine the chemical, biological and bacteriological content of the
, waters; fi0h carcasses vere examined for pesticidec; a certain algaa which
soae scientists bolieve is toxic was also studied. All the evidence
assembled indicates that water pollution is not responsible for ths alevife
deaths.
However, it is also obvious that the balance of naturs in the lake
vaters had precariously tilted. With the diosjrpoarance of natural predators,
the alewife population had exploded.
If natural checks are to be restored by the stocking of such game fich
as lake trout and coho salmon, it will also be necessary to make suro that
the waters of Lake Michigan are further protected froa contasinonts, for
game fish are sem?-,of the first victiras of pollution, as Lake Erie has so
harshly demonstrated.
This paper, besides reporting oa the water sampling program conducted
by the 1WCA, has also compiled a variety of literature on alevives. Frca
an examination of this literature, sons conclusions have been drawn which
may prove helpful in dealing with this environmental disaster.
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. A giant windrow of dead alewives is shown here in
the middle of I»ake Michigan* Some of theso windrows
extended for Uo miles and were S>0 feet in
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s~^ SPECIAL WATER QUALITY SURVEY
^J
* . The FWPCA's Chicago Program Office, Great Lakes Region, conducted
a special water quality sampling survey on June 30 > July 1, and July 2,
fallowing the eha?e 34?'^ f^auna thq la.Hg IVwt MlwuuKse, Wiaeonaifl, to
A
^ Grand Haven, Michigan.
The water's chemical, biological and bacteriological contents were
examined. Chemical tests of such pollutants as ammonia nitrogen, sulfates,
chloride, phenol, cyanide, and other contaminants did not show any unusual
levels which could be linked with the fish die-off.
Both the waters and the fish were checked for pesticides. Water
samples were relatively free of pesticide residues, but the bodies of the
fish did contain fairly large amounts of the contaminant. However,
healthy alewives have been reported to contain levels in excess of those
3
found in the examination, and lethal doses of pesticides were not discovered,
leading investigators to conclude that pesticides are not a significant
factor in the die-off.
However, the FWPCA's Southeast Water Laboratory at Athens, Georgia,
vill assist the Chicago Program Office in further pesticide studies,
comparing healthy and dying fish, and examining the liver, gill and brain
tissue of healthy alewives.
The waters were also checked for bacterial levels and temperature.
Blue green algae, which some scientists are investigating for toxicity,
was also scrutinized. There were no large concentrations of these algal
blooms at the time the survey was conducted, though.
In general, the findings did not indicate the presence of any extreme
f~\ or bizarre pollution conditions in the waters that could have caused the
massive die-off. (Details of the survey are contained in the Appendix.)
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ENVIRONMENTAL ASPECTS 07 THE PROBLEM
3
^ . The delicate balance that was tipped and led to the alewife's popu-
lation explosion cannot be blamed on any one occurrence. There are
many factors that contributed to environmental changes, including:
^^
overfishing, man-made canals, water pollution. It was an already altered
aquatic environment that was entered by the sea lamprey, another invader
fish, which gained access in great numbers to the Great Lakes with the
opening of the St. Lawrence Seaway. The lamprey is a parasitic type of
fish that is often confused with an eel because of its eel-like appearance.
The lamprey has a sucking disc set with variable teeth with which it
attaches itself to fish and, after rasping a hole in the body, sucks
nourishment from its host. The lamprey decimated what remained of Lake
Michigan's lake trout population, which had kept the alewives in check.
^J The lampreys have been brought under control by treating the headwaters
vhere they spawn with a highly selective chemical that kills off their
larvae while not harming other forms of aquatic life. The sea lamprey in
its native salt water habitat reaches a length of nearly three feet, but,
like the alewife, is much smaller in fresh water, averaging seventeen to
eighteen inches in length. The sea lamprey had been virtually landlocked
in Lake Champlain and Lake Ontario until the digging of more canals gave
it access to the other Great Lakes. An example is the Welland Ship Canal
which connects Lakes Ontario and Erie, where construction to replace the old
canal began in 1913. The lamprey may have reached Lake Ontario by swimming
up the Hudson River and on through the New York Barge Canal to the lake, a
. route the alewife is also thought to have favored.
With the lamprey under control, restocking of Lake Michigan with lake
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Flies, such as the ones spotting the carcasses above,,
came in swarms to feed on the dead alewives* In addition,
the decaying fish also brought an infestation of
maggots (fly larva), 6-20-6?
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9
and steelhead trout and coho and chinook salmon was begun. Care must
< - be exercised, however, if the restocking program is to succeed. Adult
. alewives will be available to some of these predators only intermittently
because of the nature of their migrations between deep and shallow waters.
The alewives live in the deepest wafers in mid-winter/ move along the
bottom through the intermediate depths in late winter and early spring,
and inhabit the shallow areas near shore and in the rivers during spawning.
In autumn, they migrate back to the intermediate areas. The young hatch
during the summer and spent most of their first two years at mid-depths
in the lake. A steady diet of alewives for game fish also has question-
able value. Initial laboratory feeding tests show that lake trout fed
an exclusive alewife diet for a period of six weeks became extremely low in
thiamine (vitamin Bj_) content.
<-v Other fish that the trout depended upon for food also declined in
numbers when alewives became the dominant species of the lake. Chubs
which occupied the deeper depths of the lake and smelt that lived in the
intermediate and shallow areas have fallen sharply in numbers. The cisco
(lake herring) and emerald shiners which lived in the shallower waters
have all but disappeared; the yellow perch which resides near shore is
rapidly declining. If the predator fish can reduce alewife stocks, some
of the species crowded out by the alewife may come back\ A controlled
alewife population, however, would be desirable to serve as a form of
food for the larger predators.
Such game fish as trout and salmon are also dependent on clean water.
Lake Michigan's shore waters, particularly in the southern end of the lake,
. are becoming more "enriched" by contaminants. Pollution kills off certain
O
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10
forms of organisms in the bottea muds that game fi0h feed oa. Coarse
or rough scavenger fish, such as the carp, however, can feed on other
pollution-tolerant organisas, such as eludgeworras, aquatic sowbugo,
bloodworms and leeches -- foms of life that indicate pollution. The
carp can survive in such a despoiled environment, but the game fish
cannot. They are crowded out .by the coaroa fish in the competition for
food. Dr. Stanford H. Smith, fishery biologist for the Bureau of Commercial
Fisheries, reports that carp are becoming abundant in the south end of
Lake Michigan. Lake Erie is a good example of lake "enrichment," and
what it does to gams fish. The yellow pickerel, or walleye, and the blue
pickerel have vanished, while carp and gar have established themselves in
even greater abundance.
It Is evident that a restocking progress success depends upon control
of water pollution. A Federal enforcement conference has established water
quality criteria for the south end of Lake Michigan, with timetables to
meet these standards of purity. In addition, tha Federal Water Pollution
Control Act required all States to submit water quality standards to the
Secretary of the Interior by June 30 of this year, along with 'plans for
Implementing and enforcing the standards. The Secretary will review these
standards. If they are acceptable, they will become official Federal water
quality standards. The strict enforcement of high water quality standards
would insure an environment in which gese fish could thrive and multiply.
Theories about the alewife deaths range froa shock caused by tenspera-
ture changes to the termination of e life cycle, froa starvation and
suffocation to spavaiag and thyroid stresses. It could well be that a com-
bination of events is responsible, but nore data and research are needed
before any acceptable conclusions can be drawn.
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Chicago was the first community to experience the
alewife invasion. Above is the scene at the Foster
Avenue Beach end Breakwater where a glistening
carp«t of alewife carcasses has baen washed a&hora, 6-19-6?
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13
-. BACKGROUND OF THE PROBLEM
D .
Alewife die-offs have been reported in the Atlantic Ocean since the
17001s. The alewives in the Great Lakes, unlike their salt water cousins,
however, have been drawfed in their struggle to adapt to fresh water.
*
They are about half the size of the Atlantic alewives, averaging about 6
or 7 inches compared to their Atlantic relations' 10 to 11-inch average
length. Atlantic alewives also have food value, having been sought after
first "by Indians and the settlers of New England. The name was probably
given the fish because of their puffy bellies, after the women who operated
ale houses in England.
^ The alewife of the Great Lakes has a bigger head, enlarged by salivary
glands that are overworked to maintain the same mineral (salts) balance in
its blood as its ocean relative.
^ The Great Lakes alewife also has an atrophied (stunted) thyroid. This
condition leaves it with less fat content, making it more bony, and
destroying its food value, except as food for cats or minks.
Of the estimated 20 billion alewives (l) washed up dead or dying in
Lake Michigan, the greatest die-off occurred in the southern basin. This
'is thought to be due to more extensive commercial fishing in the northern
basin. There is also a market for this fish for use as fertilizer.
l
Alewife die-offs have become an annual event in Lake Michigan through-
out the past years. Their 1967 abundance had been predicted by the Depart-
ment of the Interior's Bureau of Commercial Fisheries, which noted a record
hatch in 1964. The alewife habit of dying en masse when they spawn in the
late spring had been observed since the l880's in Lake Ontario.
5
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An estimated 20 billion alewives died in Lake Michigan during June and
July, rolling in wave after wave onto beaches in Chicago, Indiana, Michigan
and Wisconsin* The above picture was takgn at tho 79th Street Beach on
Chicago's south aids, 6-20-6?
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15
x~. Since most alewives spawn in the third year, 1967*8 bumper numbers could
be anticipated. (2)
-
Natural inhabitants of the North Atlantic, the immigrant species
of the Great Lakes was first noted in the Finger Lakes of New York in
1868, with subsequent sightings in Lake Ontario in the l880's.
The alewife has since migrated throughout the entire Great Lakes
system. Figure 1, taken from Threinen's life history of the alewife (2),
traces the progress of these invaders throughout the Great Lakes. Alewives
soon became and continue to be the most abundant fish of Lake Ontario.
/They also exist in large numbers in Lake Erie, but have not become the
dominant species there. However, Lakes Huron and Michigan support vast
populations of this fish, and each has experienced the annual die-offs
associated with spring spawning. Lake Huron preceded Lake Michigan in
^ reaching its peak population; Lake Michigan may now have reached that
stage. Whether Lake Superior will also experience explosive alewife popu-
lations remains to be seen, but progress has been made in replenishing
^ > Superior's stock of game fish which feed on alewives.
Dr. Wayne Tody (3) Chief of the Fish Division of the Michigan Depart-
ment of Conservation, observed that the alewife population of Lake Michigan
^ has increased from 1J per cent in weight of all lake fish in 1962 to 90 per
cent by 1965.
The enormous numbers of alewives deposited on Lake Michigan's beaches
Q and floating in its harbors have created massive problems for cities and
towns located along it. Drinking water intakes have been plugged up; the
. . air has become polluted with the raw aroma of rotting fish, and local
9 capabilities and creativity have been severely strained in trying to find
3
** ways and means of disposing of the wave upon wave of carcasses that have
washed ashore.
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SUPERIOR
95.4
ATWHTIC OCEAN
ef Iht AllontJj « «f invoiisn by fin
Figure 1
,
^Threinen;
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IT
ORIGIN OF THE ALEWIFE POPULATION EXPLOSION
Species Inter -
Dr. Smith, in a paper on over -exploited fishery populations in the
Great Lakes, presented at a symposium in 1966 (k), lucidly described the
f sequence of events leading to the present over -population of the Great
Lakes by alewives. Smith states that "a succession of fish species
would be expected during the natural aging process of the Great Lakes,
£ but recent progressive changes in species composition have been rapid
and obviously accelerated by influences of man, both from enrichment of
the environment with wastes, and dispoilment of the most abundant or
0 ' preferred species of f ish .. .leading to the state of biological instability
in the mid-19601 s that is almost unparalleled in fishery science." The
sturgeon was largely eliminated through fishery practices. Lake herring,
9 historically abundant, declined preciptously in the 1920's. A subsequent
decline in these stocks since the mid -19^0 's, approaching elimination in
the mid-19601 s, undoubtedly is a response to an unfavorable environment.
The lake whitefish were similarly reduced in numbers, due largely to the
introduction of the deep trap net in 1928. Over 4.1 million pounds of
whitefish were taken from Lake Huron in 1931; the catch has been less than '
200,000 pounds in most years after the 19^2 low. Combining with the
fishery over-exploitation was the impact of the sea lamprey. The smelt,
originally a native of Lake Ontario, was introduced into Lake Michigan
in 1912 and underwent a population explosion in Lakes Michigan and Huron in
the 1930' s. This population suffered severe mortality during the winters
of 19te-19lf3, probably due to a bacterial or virus disease.
3
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O
t
18
Smith generalized on the recent changes in the Great Lakes fish
./'
populations as follows:
"Until the 19^0's the Great Lakes as a whole had en-
joyed a stable and productive fishery despite loss of the
sturgeon and the few collapses.of stocks in certain lakes.
All preferred species continued in abundance somewhere in
the Great Lakes. Although many showed...degrees of...
fluctuation, the species composition of the total catch of
the Great Lakes showed no marked changes or trends....
"The major events that started in the 19^0fs involved
the upper three lakes (Huron, Michigan, and Superior).
Similar changes...apparently had taken place earlier in
Lake Ontario, but...had gone almost unnoticed because the
fishery was small. Changes that were progressing in Lake
Erie, and which have accelerated since the 19^0's, were
dissimilar to those in the upper three lakes and...were
related more to environmental change, but undoubtedly
were also influenced by (fishing) exploitation of a few
preferred species....
"The history of fishery exploitation in Lake Michigan
was typical of the other Great Lakes, The highest annual
production occurred near or before the turn of the century
when the fishery had become well established....
"Only nine species have been major contributions to the
catch and have constituted 95-6 to 99.7 per cent of the catch
in periods for which records of all species are complete.
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The scene of tiny white bodies invading a beach becoiaa
a common sight in Wisconsin, Illinois, Indiana and
Michigan, Above is the 79th Street Beach in Chicago,
with the city's South District Filtration Plant in
the background.
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so
^^ "At the turn of the century seven of these species
\*J
f vere represented in the catch. The lake trout
(Salvelinus namaycush) and lake herring were the largest
contributions to the catch, and the carp (Cyprinus carpio)
f vhich was introduced into the lake in the late 1800's
composed less than 1 per cent of the catch. Despite in-
creased abundance of carp and the subsequent introduction
f and establishment of the smelt, the relative contribution
of the native species to the catch showed no marked changes
\
or trends until the 19^5-^9 period when the lake trout
A catch declined sharply. Subsequent species changes took
place in swift succession and by 19&5 "the catch was dominated
by the alewife (Pomolobus pseud oharengus) which invaded the lake
11| (Michigan) where it was first recorded in 19^9j exotic species
constituted nearly 63 per cent of the catch, and the portion of
the catch composed of lake trout, lake herring, suckers (Catostomus)
f and whitefish which exceeded 82 per cent in the 1898-1909 period,
was only ^-.5 Per cent in 19^5.
"Several factors contributed to this extreme change, and
9 the interaction of these factors and the exact mechanisms that
brought about the change are incompletely understood . There
x
is no question, however, that predation of the sea lamprey
V triggered the decline of the lake trout in the upper three
Great Lakes, and that the resultant pressures of a shifting
fishery, and a population explosion of the alevife were major
W contributing factors ....
D
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21
"It is apparent that in all three of the upper Great
Lakes the abundance of sea lampreys we3 very low at the
tiirie when lake trout stocks started to decline. There is little
^f
question that the lake trout were the prime prey of the
o?
sea lamprey and lake trout were the only abundant species of
large fish that inhabited the deepwater (subthermocline)
regions of the lakes.
"The small amount of exploitation by the sea lamprey
that precipitated the decline of the lake trout stocks
provides evidence that the commercial fishery had been
operating at near the optimum rate of exploitation."
Smith concludes as follows: Following the decline of the lake trout,
the chub became the last species of importance in the fishery of Lake
Michigan. The consequence of the pressure of commercial exploitation
and the preying of the sea lamprey, combined with the alevife out-competing
them resulted in the sharp decline of the chub population. This
competitive advantage of the alewife undoubtedly speeded a population
explosion of alewives in Lake Michigan that gained its greater impetus
in the 1960's.
To summarize, Lake Michigan was left with a fish population consisting
largely of one species, the alewives. The natural enemies of the
alewives, the predatory fish species,could no longer assert a controlling
effect in maintaining a balanced fish population.
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22
C*~) Physical Description of Alewives
* _ Threinen (2) describes the alewife as follows:
"The alewife like other herring has soft fins, lacks teeth, has no
adipose fin, and has a forked tail. This species is characterized by a
knife-edge belly and a saw-like arrangement of scales on the edge, hence
the name sawbelly. This herring can be distinguished from its near
relatives by its relatively heavy build forward, thin body, its big eyes
* and a short upper Jaw and projecting lower jaw. The body is about 3|- times
as long as it is deep. Color of the back is a grey-green or brownish green
vhich becomes a bright silvery color on the sides and belly. The cheek is
also silvery. The larvae are transparent, have large eyes, and black pigment
cells along the ventral portion of body."
Reproduction
^~* When making its home in the waters of the North Atlantic, the alewife,
like the salmon, goes up fresh water streams to spawn In the Great Lakes,
the spawning and egg laying usually )occurs in the shallow shore waters
of the lakes. In Lake Michigan, this spawning generally occurs between
April 15 and July 1. Female alewives in fresh water have been observed to
contain 10,000 to 12,000 eggs, according to Threinen (2), and the more
prolific salt water species deposits 60,000 to 100,000 eggs. Threinen (2)
also observes that the salt water dwelling adults return to salt water
soon after spawning and the young migrate to salt water throughout the
latter part of the summer when they are two to four inches long. In the
fresh vater, the young remain around the spawning grounds until the late
^ larval stage is reached.
^-v Laboratory eggs kept at $6 to 60° F in running water hatched in 8l to
102 hours.
%
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2<3
v^
Alewives in the Great Lakes have been dwarfed in
their struggle to adapt to fresh water, averaging
only six to seven inches compared to the average
11-inch length of their Atlantic cousins* Their
size is shovm here in relation to the dead carp
in the left of the picture» 6-20-6?
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O Habits and Habitat
"IU-J r V T '"T""1Ti»«---- -'- T C-7
^ Threinen (2) describes the habits and habitat of alevives as follows:
"Alewives are ... a ... gregarious fish (they flock together). in
the ocean, schools as large as ^0,000 fish have been observed. In Lake
V Michigan schools of spawning fish were thought to number 5>000 to 6,000
individuals in schools 15 to 20 feet in diameter. While on the inshore
migration they come into shallow water at night and remain off-shore during
w the day. In late August they migrate to Seep water. Test netting in the
Finger Lakes yielded alewives at all depths down to 160 feet. Test netting
in Lake Ontario revealed that alewives were most abundant between 30 (l80
^ feet) to 50 (300 feet) fathoms. Following spawning, some mortality of
adults has been observed among the ocean migrants. Lake Ontario populations
have been periodically subjected to large summer die-offs when the adults
enter shallow water. This phenomenon has been correlated with water
temperature changes, the alewife being unable to adjust to the 10° C.
(50O F.) temperature gradient between deep and shoal water. The alewife is
characterized as being unable to adjust to respidly rising or fluctuating
temperatures. It is also a fragile fish which will not stand much handling."
Food Habits
The main staple of the alewife diet is animal planktonic organisms.
In a study made on Seneca Lake, New York, alewives showett that h6% of the
volume of stomach contents vere microcrustacea. Threinea (2) also observes
that in this New York study 24 specimens captured in Lake Ontario had eaten
mostly Mysis relicta, an opossum shrimp inhabiting deep water, and some
Pontoporela, a deep water scud. It was concluded that alewives rarely take
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w 25
/\ fish, eat chiefly animal plankton, and take other food if available. Salt
A vater alevives cease feeding vhen they go up fresh water streams to spawn.
Growth
The Great Lakes alewives do not reach a cize comparable to those
^ occurring in the North Atlantic Ocean. The ocean alevives attain a length
of 15 inches, with the average size "being 10 to 11 inches and 8 to 9 ounces.
The average length of the fresh water alewife is about 6 inches. Threinen
^ (2) observes that apparently few Atlantic alevives live beyond 5 or 6 years.
Economic Value
The alevives from the Great Lakes to date have had low commercial value.
% Most of the catch is used for animal food or fertilizer. Threinen (2)
states that soice of the salt water catch is salted, srcoked, or pickled like
other species of herring. However, the thin body and many email bones detract
from its valua. Much of the Wisconsin production becomes mink food. Eastern
fish hatcheries have used alevives as trout food.
D
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THEORIES ON THE ALEWIFE DIE-OFF
There has been much speculation as to vhat causes the annual alewife
. die-off. Theories include starvation; ternperature shock during the migration
from cold deep waters to shallow spawning waters; natural death at the end
of a three-year cycle; toxic algal blooms; oxygen depletion in spawning vaters;
* disease; spawning stress; extreme sensitivity of the ale-wife, end an
osmotic stress associated with the alewife1s struggle to make the adjustment
from salt to fresh water.
Preliminary data compiled by the Bureau of Commercial Fisheries has
established that the number of yearlings among the dead is greater than in
previous years. Twenty per cent of a random sample taken from a half-mile
of beach south of Saugatuck, Michigan, were yearlings. Based on data from
samples being examined in laboratories, yearlings account for 28 per cent
Q of the total.
There ip also a scarcity of two-year-old fish, the bureau reports. This
age group occupies midwater levels and is not caught in bottom trawls. The
two-year-olds begin to join the adult stocks on the lake bottom in July. By
November, almost all have migrated to the lake bottoms.
Both sexes are represented among the dead fish, the bureau adds. Most
of the adult females examined had not spawned, so the die-off is not being
associated at this point with a post-spawning mortality. There is also
little indication of emaciation. Approximately one-half of the dead alewives
_ examined had soma food in their stomachs.
There was also a significant die-off during the winter. Bottom trawling
In April by the R/V Cisco produced far greater numbers of dead end partially
. decomposed alewives than had been observed in previous years.
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o
*
Ten days after they were washed ashore, the alewives had
decomposed to the extent shown above on a Chicago baache
The bones of decomposed aleid.ves can be a hazard to the
feet of bathers, 6-30-6?
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t 28
^^^ The Bureau of Coimarcial Fisheries is pursuing an investigation into
- the role played by temperature and thyroid exhaustion as a possible cause
* - of die-off.
Although all the functions of the thyroid are not understood for fish,
it has been suggested that it is related to grovth, osnjotic regulation, and
%
temperature tolerance. Alewives are subjected to sharp temperature changes
as they move shorevard in the spring and early summer. Thyroid exhaustion
also provides a possible theory for t^ mid-winter mortality since it is
believed that the thyroid hormone produces resistance to lov temperatures (5).
The alevife is subjected to extreme temperature fluctuation vhen it
migrates from the cold (9 degrees centigrade) deep vaters of the lake to the
varmer (19-20° C) shoal areas and tributaries to spawn. Laboratory studies
have shown such fluctuations to cause fish deaths (6). Field observations
*~\ by Dr. Smith and other Bureau of Commercial Fisheries personnel have
substantiated the laboratory findings. Although a disease factor could be
present, no evidence is available to support this thesis at present.
^ The association of springtime "blooms" of certain toxic plankton vith
alevife mortalities has been mentioned by Woods (7) and Williams (8). Woods,
hovever, states that this theory has not been demonstrated.
The theory that alewives spawn in shallow sluggish vaters in such
numbers that they exhaust the existing oxygen supply and suffocate vas
dismissed after oxygen tests vere run (9).
McKim (10) stated that the temperature fluctuation thesis might best
explain the larger numbers of young fish dying this year. The rise in
. . alevife population, followed by mass mortality, has occurred as the population
moved each year up through Lake Huron and dovn through Lake Michigan. If
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29
Lake Michigan "behaves as Lake Huron did, the oLevife population in southern
o
>^ Lake Michigan should stabilize, according to Dr. Smith. Die-offs vill be
seen each year as always, but chould ba hardly noticeable, as is now the case
in Lake Huron/ Dr. Ssiith balieves.
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t . 3°
EXTENT OF THE ALJMIFE DIE-OFF IN THE GREAT LAKES, 1967
v y
According to Greenwood (ll), alewlfe mortality vas reported from
* . Saginaw Bay (Lake Huron) during this year, He also reported that an alewife
kill vas noted in Lake Erie during the latter part of the past winter.
According to Smith (12), serious alevife die-offs have occurred in Lakes
^ Ontario, Erie, end Huron in the past. It is probable that the peak years
of abundance have occurred in these lakes. However, annual kills still
occur.
%
Although neither Greenwood nor Smith estimated the alewife kills in
each of these lakes in 19^7> Smith (12) stated that the current die-off
in southern Lake Michigan was the greatest of eny local die-off that he had
observed in the Great Lakes.
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31
INTERFERENCE TO WATER USES BY THE ALEWIEE DIE-OFF
000 gallons of deodorant to try to overcome the smell (13)-
% Alewives clog intake pipes and f^^er screens leading into water treat-
J
ment plants, electric utilities and factories. A steel plant on the southern
C3
shore of Lake Michigan estimated a loss of approximately half a million
dollars a day for about 10 days in April 1966 -when cleaning screens on the
cooling vater system were unable to cope vith alevives entering the intakes.
The screening system vas inadequate even though it removed 60 tons of fish
per day. Electric power generating plants in Illinois vere seriously affected
at about the same time vhen it became necessary to alternately shut down
half the generators while cooling water screens on the other half were cleaned.
In April 1965 > Chicago's new Central District Filtration Plant operated at
reduced capacity when alewives caused breakdowns to 20 per cent of the
cleaning screens which were handling 10 tons of fish per hour. This vater
system was protected in 1966 by the installation of an alewife diversion
system
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O
A water skiier tiptoes over dead alewives littering
the 79th Street beach in Chicago to get to the boat.
This is one example of how the massive fish die-off
has interfered with recreational uses of the beach
front. 6-20-6?
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The alewife is troublesonia to Great Iiakes commercial fishermen because
they snag easily in perch gill nets (15)- Further, alewives compete with
ciscos, a more valuable commercial fish. A decline in the shallow water
Cisco has paralleled an increase in the number of alewives in South Bay
(Lake Huron), Saginav Bay (Lake Huron), and Green Bay (Lake Michigan). The
rapid build-up of alewives in the Great Lakes is thought to be the result
of the disturbed inter-relationships between species caused by the sea
lamprey and by over fishing. Lake trout end burbot are predators of the
alewife. The recent decimation of their mtnibero probably resulted in the
Increase in alewife populations.
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3*
.r-v RESEARCH AND STUDIES ON THE ALEWIFE PROBLEM
Dr. Smith, Mr. Greenwood, and other personnel of the U. S. Bureau
of Commercial Fisheries, Ann Arbor, Michigan, have studied the alewife
extensively. Dr. Smith (12) stated that othorr etudico bolng conducted on
the alewife includes a study on the ecology of the alewife in northern Green
Bay by the Michigan Institute for Fisheries Research; a study on the diurnal
feeding jBOvements of the alewife in the Milwaukee area by the University of
Wisconsin, and a study of the food of the coho salmon and the lake trout
In relation to the alewife by the Michigan Institute for Fisheries Research.
Various Great Lakes states have revised commercial fishing regulations
to permit a larger harvest of the alewife and to protect such alewife
predators as the lake trout, coho salmon, and chinook salmon (15)'
Greenwood stated that the exploratory branch of the U. S. Bureau of
Commercial Fisheries has been conducting studies in Lake Michigan since
1962. Some of the objectives of the agency are to obtain information on the
availability of the alewife for commercial uses and to obtain information
on more economical ways of processing and handling alewives. In order to
obtain information on the annual relative abundance of fish, samples of the
various year classes of the fish ore collected each November In the
Saugatuck area.
Mr. Greenwood states that the Province of Ontario is making a study of
alewives In the island area of Lake Ontario.
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35
-^ DISPOSAL AND CONTROL METHODS ON THE ALEWIFE PROBLEM
A The disposal of dead and decaying alevives demands Immediate action
of agencies Involved vith recreation on beaches and in harbors. Usually,
the fich ere raked up or ocraped up by hcmd ohovolo and/or tractor lifta
A and placed into trucks. They are then transported to public or private
dumps where they are buried. In some cases, the fish are buried to a
depth of h or 5 feet on the beach. Equipment includes sand sifters
9 to separate fish from sand. Although disposal might include burning of dead
alevives, such action would result in air pollution. Deodorants have been
applied to dead fish and the beaches to reduce the stench of decomposition.
9 In some cases, chemicals are used on beaches to control fly maggots in tha
dead fisn.
The use of trawlers to catch and remove the fish before they reach
the beaches has been suggested. Nets placed around vater intakes can
prevent alewlves from entering the vater system. Chicago protected ito vater
supply by installation of an alewife diversion system in 1966 (l4).
Methods of alewife control are varied. Alevives can be processed into
animal food and fish meal. Commercial trawling is an effective vay of
catching alewives, according to Greenwood (10). He estimates that during this
year 50,000,000 pounds of alewives vi.1,1 be taken from Lake Michigan and
processed at grinding plants now operating at Menominee, Michigan, Milwaukee
and Pensaukee, Wisconsin. Possible future expansion in the business may
result in the removal of considerable numbers of fish in their first and
second years of life and reduce the number which seem to die naturally in the
third year of life. Fish predators can aid in the control of alevives. Lake
trout, coho salmon and chinook salmon are predators of tha alevife. According
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r
Q
A Beverly Shores Volunteer Fire Bopartment truck
sprays deodorant on dead alewivss to reducs tha
smell of rotting fish, 6-26-6?
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38
selected for many generations to develop a strain that vlll occupy deep
o
^^ water, grow fast, and mature early. Michigan and Ontario have also initiated
experimental introductions of kokanee in the Lake Michigan watershed end
in Georgian Bay, Lake Huron. Although it is uncertain where the kokanee will
live in the Great Lakes, they will probably compete with the alewife.
"It eeems unlikely that all of these introductions will meet with great
success. It is certain, however, that the sea lamprey will be controlled,
as it has been in Lake Superior, and that conditions again will be favorable
for large predators in the deepwater areas. Establishment of at least
the lake trout seems to be assured because of its rapid recovery in Lake
Superior that followed completion of the initial sea lamprey control measures
in 1961. The successful establishment of at least one additional major
predator in the deepwater area would place even greater pressure on the
alewife as the principal forage species. Thus, the alewife which reached
the peak of its population explosion in the mld-19^0fs and is subjected to
heavy commercial exploitation, certainly must decline as substantial
populations of predators are established."
In another communication, Dr. Smith also observed that "we know that the
shore waters of Lake Michigan, particularly in the southern end, are
becoming richer and the carp that thrive under such conditions are becoming
more abundant. Other species favored by this enrichment may also become
more abundant. Species that increase under those conditions are usually
'rough fish1 and should be harvested as they often compete to the disadvantage
of game fish."
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39
(3 t CONGRESSIONAL CONCERN OVER THE ALEWIFE PROBLEM
As the dimensions of the alewife die-off became known, Congressional
interest grew. There was a public clamor for action to clean up the teaches.
Sen. Gaylord Nelson (D., Wis.) introduced Senate Bill 2123 on July IT asking
9 ' '
for $5 million to seek to control the elevlfe problem. The bill would
*
provide matching grants to states for research into ways to reduce the tens
of billions of alewives in the Great Lakes. Nearly all the 16 senators
from the states bordering on the lakes will back the legislation, according
to Sen. Nelson's office. A companion measure, RR ^793, was sponsored in the
House of Representatives by Rep. Clement J. Zablocki (D., Wis.). A similar
bill has also been introduced by Rep. Henry C. Schadeberg (R.,Wis.).
Congressional inquiries were directed to the Federal Water Pollution
Control Administration from elected officials from throughout the Great
Lakes. Inquiries came from Sen. William Proxmire (D., Wis.); Senators
Philip A. Hart and Robert P. Griffin of Michigan; Senators Birch E. Bayh
and Vance Hartke of Indiana; Senators Everett M. Dirksen and Charles H.
Percy of Illinois; Senators Eugene J. McCarthy and Walter F. Mondale of
Minnesota; and Sen. Robert Kennedy of New York. Congressmen who have been
in touch with FWPCA personnel include Rep. Raymond J. Madden (D., Ind.)
and Rep. William A. Steiger (R., Wis.).
Sen. Hartke (D., Ind.), another sponsor of the alewife control bill,
toured beaches in Michigan City, and in Gary with that community's mayor,
A. Martin Katz. Afterward, Sen. Hartke said he never fully appreciated the
problem until he actually saw end Bmalled the fish.
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IK)
o.
v~--» «i~??inTvr«-~t. I" "1 f~ =-| -r-'-CT^rg-"'^_~-^.
s-.j\ \ 1_^«r^
ME- >-^**!vi "a^^r~ T ~ - ;, ! v * *.' J
fc^^-v^^^-'^:"'^ivc^^^rJ^^^ .---- '" ^^x"^
-
[&«^C-*
3 \ I* **' j>" % * ~ 'I v "-*.*'l '" ** "** '*" -*y"^^ t » ^/ \- if^f "'v *"i " '-^'"'^' ^-'J Jrf "
Chicago's Burnham Harbor on Juna 30 was a stinking
mass of dead alewives and algae. 6-30-6?
o
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Letters and telephone calls from concerned resort and summer horns
ovners and vacationers have also rained into the Great Lakes Regional Office,
IWPCA, in Chicago.
A number of Congrouarnon inquired about tho pooaibXa uao or mcmboro of
the Job Corps, vho are enrolled in one' of the programs conducted by the
Office of Economic Opportunity. Approximately 110 Job Corps members have
since "been engaged in clean-up activities in the Indiana communities of
Gary, East Chicago, Whiting, Beverly Shores, and Michigan City. Along the
Michigan shoreline "between Benton Harbor and Ludington, between ^0 and
100 Corpsmen have been deployed for the clean-up. Twenty-five Job
Corpsmsn from the Camp McCoy center in Sparta, Wis., vere the latest vork
force to help vith disposal of the fish. They arrived at the Illinois Beach
State Park near Zion, HI., on July 2^ to begin clean-up operations. Job
Corps aid had been requested by Senators Dirksen and Percy. Job Corps
workers are also available for duty in other states if their services are
rerjuested.
Sen. Bayh inspected the alewife problem in Lake Michigan on July 21,
vhen he vent on a tvo-hour boat tour vith federal, state and local officials,
traveling from East Chicago to Michigan City, Ind. Accompanying Sen. Bayh
on the inspection vere: H. W. Postorr,? Great Lakes Regional Director, IVPCA;
Raymond Clevenger, Chnlrman of the Great Lakes Basin Commission of the
President's Water Resources Council; Ernest Premetz, Deputy Regional Director
of the Bureau of Commercial Fisheries and Wildlife; Blucher A. Poole,
chief of environmental sanitation for the Indiana Board of Health; John
Mitchell, director of the Indiana Department of Natural Resources, and
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*-*. John Nicosia, mayor of East Chicago.
^ Representatives from the AUis-Qialcsrs Co., whose equipment is
currently used by the cities of Gary and Michigan City to remove fish from
the bcashos, and Aquatic Controls Corpt, vhoso machinery removes fish from
^ the water, vere also present to brief-the group.
Sen. Bayh, who is a cosponsor of the bill to provide $5 million for
alewife control, said he will also support efforts to obtain funds for
^ clearing the alewives from the beaches. He said that vhile it is too late
to prevent alevives from littering the beaches and shoreline this year, the
$5 million study vill help to alleviate the problem in future years.
0 In addition, he added, ways must be found to help local officials
clear the alewives off their beaches to prevent possible health and pollution
problems and to salvage recreational beach uses.
Rep. Zablocki has also called on Mr. Clevenger, as Chairman of the Great
Lakes Basin Commission, to arrange a conference on the alewife problem so
that information may be exchanged and efforts for dealing with the crisis
coordinated between the various levels of government.
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COUCLUSIOHS
Big alewife die-offs have occurred in Lakes Ontario, Erie, and Huron
in the past, vith kills of lecser magnitude occurring in these lakes the
v
last few years. The alewife die-off that occurred in Lake Michigan during
June and July 196T, however, was of unprecedented proportions. The great
size of the die-off is no doubt linked in some way with the unstable balance
that exists between the alevives and their predators. Unchecked by natural
predators, the alewife population appears to have exploded.
Causes of this nasoive die-off, though, remain speculative. Many
theories have been advanced to explain it and past die-offs, including:
starvation, teiaperature shock during migration from the cold deep waters to
shallow warm waters for spawning, natural death at the end of the life span,
toxic plankton blooms, oxygen depletion in spasming areas, and thyroid ex-
©
haustion.
There is an obvious need for more long-term research into the problem.
^ While the alewife has been a conspicuous nuisance in nost of the Great Lakes
for many years, the 1967 die-off presented a huge disposal problem never
before encountered. While all available evidence indicates that water
0 pollution is in no way responsible for the deaths, the alewives do become a
pollution problem when they die and are washed ashore, littering beaches and
harbors to interfer with naay water uses. The unsightly appearance and
0 obnoxious smell of decaying alewife carcasses are repugnant to bathers, boaters,
and other users of water. Alewives have clogged intake pipes and filter
, . screens leading into water treatment plants, electric utilities and factories.
0 They ere troublescsaa to commercial fishernan because they gill easily in parch
/""S , nets, and they have replaced other nore valuable fish such as the cisco and
chub.
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to
O Restocking of fish that prey on the alewivcs and Increased cccnaercial
fishing for them should prove helpful in restoring a balanced aquatic
environment to bring the alewife population under control.
There is also n need for programs which will concern themselves with
the more immediate problems of cleaning up the beaches end finding ways of
removing the fish frcin the water before they reach the shore. In this regard,
increased trawling for the fish should also be considered.
The Secretary of the Interior has appointed a six-man task force, headed
by Dr. Stanley A. Cain, Assistant Secretary of the Interior for Fish, Wild-
life and Parks, to study all aspects of the problem.
Studies of the alewife are also being conducted at the U.S. Bureau of
Ccssnercial Fisheries, Ann Arborj by the University of Wisconsin; by the
Michigan Institute for Fisheries Research, end by sosie of the Provinces of
Canada.
Various Great Lakes States have passed regulations to encourage heavier
harvest of alewives and to prevent ccraercial exploitation of alewife preda-
tors. Such measures, however, are not expected to produce teaediate results,
since it is believed that it will take scssa tixia for the predators to
establish themselves in the lake waters in sufficient nunbers to exercise a
controlling influence over the alewife population.
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1*5
O
A boat owner tries to clean out alewives which have
collected in Chicago's Burnham Harbor with an outboard
motor. 6-23-6?
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O,
APPENDIX
j
List of References
Special FWPCA Lake Michigan Water Quality Survey, Juno-July 196?
References
News Clippings
c?
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LIST OF REFERENCES
0'
(1) Warden, R. "20 Billion Dead Alewives." Chicago Daily News, June 21, 1967
* (2) Threinen C> W*'.'. "Life Histoiy, Ecology and Management of the
V_.
^ Alewifo." Wisconsin Conservation Bulletin Publication 223 (19£8).
(3) "War on That Fish Smell Is Escalated." Chicago Tribune, July 12, 196?.
(li) Smith, Stanford H. "How Man Changed His Planet." Symposium on
Overexploited Animal Populations, Species Succession and Fishery
Exploitation in the Great Lakes, A.A.A.S. meeting (1966).
(j>) Bureau of Commercial Fisheries memorandum.
(6) Graham, J.J. Observations on the Alewife$ Pomolobus pseudoharengus
_ (Wilson), in Fresh Waters. Publication of the Ontario Fisheries
Research Laboratory No. 7h (1956).
(7) Woods, L.P. The Alewife. Chicago Natural History Museum Bulletin,
Jj^ November I960.
(8) Williams, L.G. Possible implications of plankton populations and alewife
fish kill, May and June 196? Memorandum from Williams to Grover Cook
£ via H.W. Poston, July 6, 1967.
(9) Poston, H.W., Great Lakes Regional Director, FWPCA. Alewives. Memorandum
from H.W. Poston to Charles Pierce, Press Officer, Office of Public
£ Information, FWPCA, Washington,D.C« June 21, 196?s
(10) McKim, J.M., research aquatic biologist, National Water Quality
Laboratory, Duluth, Minnesota. Alewife Mortality in Southern Lake
0 Michigan. Memorandum from J.M. McKira to H»W. Poston, July ls 1967.
* (11) Greenwood, M.R. Information on alewives* Telephone call to M.R. Greenwood
. f from H.J. Fisher, July Hi, 1967.
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I .
Environmental Prelection Agenoy
230 South Doc. ".born S tract?
Cilcc^g IlAlicio 6060*1
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* LIST OF REFERENCES (Cont.)
0
12) Smith, Stanford H, Information on alewives. Telephone call to
Stanford H. Smith from H.J. Fisher, July Hi, 196?.
3) Black, Robert* Information on alewives. Telephone call to Robert
jplfteis frem H,.J, fliehai', ifuiy i?^ 3-9^7.
k) Premetz, Ernest. The Great Lakes Alewife Invasion. Information
paper, Bureau of Commercial Fisheries.
,) Michigan Coho ranging wide in lakesj Indiana to aid in protection,
;' The Great Lakes Newsletter, Great Lakes Commission, XI, No, U, March-
/ April 1967,
'II) Greenwood, M.R, Information on alewives. Telephone call to M.R, Greenwood
from H.J, Fisher, July 17, 1967.
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