Wetlands
Values and
Management
U.S. Fish and Wildlife Service and
U.S. Environmental Protection Agency
Washington, D.C.

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Contents
Page
Introduction	v	 1
Freshwater Marshes	 2
Swamps			 3
Bogs	 4
Lake and Shoreline Marshes	 4
Prairie Potholes	 5
Salt Marshes		 6
Artificial Marshes	 7
Wetland Values 	 8
Hunting and Trapping	10
Aesthetic Values	11
Agricultural Values	12
Values to Society	13
Wetland Management	15
Waterfowl Production	16
Managing Water	18
Dredging, Diking, Ditching	20
Water Control	21
Other Management	22
Preserving Your Wetland	24
For More Information and
Assistance	25

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Wetlands Values and
Management
by W. Alan Wentz,
South Dakota Cooperative
Wildlife Research Unit j
Wetlands are unique environments. They
are usually characterized by shallow or
fluctuating water levels and an abundance
of aquatic and marsh plants.
Different kinds of wetlands occur
throughout North America. Although each
wetland is different, we generally refer to
them as marshes, swamps, bayous, bogs,
potholes, sloughs, or just ponds. Biolo-
gists use more specialized classification
systems to define the structure and func-
tion of different types of wetlands. In this
publication the more generalized terms
will be used.
The values of wetland areas are usu-
ally taken for granted and often over-
looked. Because of this many of our
wetlands have been drained, filled, or
otherwise destroyed. For many years,wet-
lands were regarded as "wastelands" that
could be used for dumping refuse, drain-
ing for agricultural use, or filling in for
building sites. Since colonial times nearly
half of our U.S. wetlands have been
drained and even today 200 to 300 thou-
sand acres of U.S. wetlands are
destroyed each year. Today we know that
wetlands have many values and that
those values are lost when the wetland is
destroyed.
Many people and organizations are
concerned about the loss of wetlands and
their values. This concern has been
expressed through a variety of personal
actions and laws that protect wetlands.
However, in many cases,simple protection
alone is not adequate and wetlands must
be managed to maintain and enhance the
natural values that they possess. This
publication is designed to help explain
some of the values of natural wetlands
and to describe a few of the management
techniques that are available to private
landowners.

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Freshwater Marshes
There are many kinds of freshwater
marshes. Freshwater marshes include
shoreline wetlands, small woodland
marshes, prairie potholes, springfed
pools, river oxbows, bogs, and even artifi-
cial or man-made marshes. The water
supply for such wetlands might be direct
rainfall, runoff from the surrounding area,
groundwater, surface springs, or streams.
Freshwater wetlands vary.greatly in size
from a few square yards to thousands of
acres. These wetlands are usually found
in some type of landscape depression or
at the edge of lakes or rivers. They have a
great variety of plants, but they are usually
dominated by herbaceous vegetation,
such as cattails, bulrushes, grasses and
sedges, smartweeds, waterlillies, and sub-
mersed pondweeds.
Even seemingly minor wetland areas
such as tiny wet meadows or small stands
of willows along a river are important.
These "riparian" wetland areas, although
very small in size, are valuable for filtering
the water that moves slowly through them
and because they provide habitat for
many types of wildlife, such as songbirds.
These small wetland areas add greatly to
the scenic quality of any river or stream.
Riparian wetlands are vulnerable to man-
induced changes in water flow and, unfor-
tunately, even slight modifications of the
natural streambanks can easily destroy
them.
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Swamps
Swamps primarily occur throughout the
southern U.S., coastal areas, and the
Great Lakes and New England area. They
are dominated by woody vegetation.
Northern swamps usually are character-
ized by cedars, maples, ashes, willows,
and alders, while in the south, bald
cypress, tupelo gum, and oaks tend to
dominate. Swamps are often wet during
part of the year and dry during the rest.
During the wet season many of the trees
are dormant. Swamps may be any size
and some of the largest are associated
with major river systems, such as the
Mississippi. These river swamps are
known as bottomland hardwood swamps
due to the predominance of large stands
of trees. Swamps are important areas for
wildlife and fish and they provide many
valuable products, such as timber, cray-
fish, and other products. Swamps
associated with river systems are
extremely valuable in flood control
because they slow downstream flows and
help to even out flood peaks.
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Bogs
Lake and Shoreline Marshes
Bogs are a common type of freshwater
wetland in the northeastern U.S., the
Great Lakes region, and much of Canada.
Bogs are usually dominated by sphagnum
mosses, insectivorous plants, such as the
pitcher plant, and a variety of specialized
shrubs, such as leatherleaf and bog birch.
The accumulation of dead and decaying
vegetation intertwined with the roots of
living plants often forms a "quaking mat"
that extends over the open water of the
bog. Bogs are often characterized by
rings of distinctive vegetation that include
a variety of trees, such as black spruce,
larch, and northern white cedar. Although
bogs are very nutrient poor they do pro-
duce valuable products, such as cranber-
ries. In some areas water levels are
regularly manipulated to produce large
crops of cranberries and some types of
blueberries. Even the accumulated peat
deposits of bogs are valuable for use in
home gardens or as an alternative fuel
source.
Lakeside marshes are probably our most
common kind of freshwater marsh. These
small wetlands consist of narrow bands of
vegetation around the border of lakes or
small pockets of water that exist behind
lake beaches. Lake and shoreline wet-
lands filter water that flows into lakes
thereby helping to maintain water quality
in the lake. They also provide landscape
diversity and beauty around the lake in
addition to their importance as habitat for
fish and wildlife. In many lakes natural fish
production is dependent on associated
wetlands and without them fish stocking is
needed to maintain game fish popula-
tions. When lakeshore homes are built
these small wetlands are often bulldozed
out for marinas or filled in for building
sites. Careful planning could preserve
these small areas and their values.
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Prairie Potholes
Prairie potholes are found in Minnesota,
the Dakotas, surrounding states, and the
adjacent Canadian provinces. They are
widely known as the "duck factory" of this
continent due to the large numbers of
ducks produced there. At one time the
prairie potholes were widespread and
abundant. Today they are greatly reduced
in distribution and abundance because of
drainage for agricultural uses. Prairie pot-
holes are extremely productive environ-
ments. They are cyclic in nature as a
result of periods of drought on the Great
Plains. The cycles of drying and reflooding
help to maintain high productivity of water-
fowl and other marsh products. Prairie
potholes vary in size from less than an
acre to several square miles. Some are
wet for only a few weeks each year, but
even these are important because they
are used by breeding waterfowl and they
help to replenish soil moisture on crop
and rangeland. The abundance of prairie
potholes in some areas makes them
important in floodwater control and
groundwater recharge.

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Salt Marshes
Extensive salt marshes and brackish
marshes occur in North America, primarily
along the coasts. They are dominated by
salt-tolerant plants, such as the cord-
grasses, and are greatly affected by tides.
These important marshes have many val-
ues for modern man. Salt marshes are
spawning and nursery areas for fish and
shellfish of the oceans and estuaries and
without them commercial fishermen would
be out of business. They provide buffer
zones that can protect homes from ocean
storms and they help to filter out water
pollutants. Salt marshes provide refuge
for wildlife and waterfowl concentrate in
them in high numbers during the winter.
They are places of great beauty at all
seasons and they provide many recre-
ational opportunities.
At one time drainage for mosquito
control was prominent on our coastal
marshes. Extensive ditching is still visible
in many areas, but today new techniques
of mosquito control have made drainage
unnecessary. Slight manipulation of salt
marsh and brackish marsh areas can alle-
viate mosquito problems by consolidating
very small water holes into larger marsh
openings and by opening other areas to
tidal action. A combination of the tidal
action and the introduction of small mos-
quito-eating fish into the larger openings
will discourage mosquitoes. The creation
of these larger open water areas also
attracts water birds of many kinds. Such
manipulation has been so successful in
some areas that mosquito pesticide use
has been nearly eliminated. Some states
have recognized the values of their salt
marshes and placed severe restrictions
on any destruction of these important
habitats.
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Artificial Marshes
In some areas where natural marshes
never existed or where they were drained
many years ago, people have created or
restored marshes. Such marshes are usu-
ally made by diking off parts of lakes or by
building dikes on upland sites. Water lev-
els are controlled by pumping or manipu-
lation of water flows. Such artificial
marshes have become very important in
some areas where few natural marshes
now exist. These artificial marshes pro-
vide much needed habitat for waterfowl
and other wetland bifds and mammals. In
most cases such artificial marshes are
very productive and may provide water
sources or other benefits. Their continued
maintenance depends on proper manage-
ment and the continuing expenditures of
agencies or individuals. Many of these
marshes are owned and operated by pri-
vate hunting clubs or wildlife agencies
that receive their operating funds from
hunting license dollars. The contributions
of these agencies and individuals are very
significant.

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Wetland Values
Wetlands have many values including
wildlife production, recreation, aesthetics,
agricultural uses, groundwater replenish-
ment, pollution and sediment control,
flood prevention, and educational and sci-
entific uses. These values are available to
the individual landowner and to society as
a whole. Many of these values provide
little or no economic return to the land-
owner who might be able to make money
by converting the wetland to some other
use, such as cropland or building sites.
Fortunately for society, many farmers and
other landowners do maintain their wet-
lands because they appreciate the beauty
and natural values of their wetland more
than the extra dollars they might receive.
This publication is designed to help indi-
vidual landowners increase or enhance
those natural values by management and
to provide information on other options
that might result in the long-term preser-
vation of wetlands.
Wetlands provide obvious wildlife
benefits. Numerous species, such as
frogs, waterbirds, alligators, and many
others, depend on wetlands throughout
their entire life cycle. Other species, such
as deer, geese, and some fish, may
depend on wetlands for part of their lives.
The range of animals that live in wet-
lands is truly amazing. Fish, such as
northern pike, may use lakeside wetlands
as spawning grounds and migratory birds,
such as mallards, will use different wet-
lands in several states for courtship, feed-
ing, nesting, and wintering. Upland
animals, such as whitetail deer and
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pheasants, may depend on wetlands for
winter cover or even for areas to raise
their young.
The values of wetlands to wildlife can
be only partially calculated in economic
terms. While later pages in this booklet
will stress the money to be made from
wildlife in wetlands the greatest value of
wetlands wildlife must be the aesthetic
beauty and the feeling of kinship that
humans sense from these animals.
Wetlands provide numerous products
that humans use. Some communities hold
festivals that revolve around wetland
products such as muskrats, ducks, or
crayfish. Animals that are hunted and
trapped are used for food and clothing.
Beyond these obvious products wetlands
also produce such things as bullfrogs, fish
bait items such as minnows or leeches,
and specialty plant foods such as wild
rice, cranberries, and even cattail. The list
could go on and on, and would include
such items as dried plants for flower
arrangements and live insectivorous
plants. Many landowners have developed
sound management and harvest pro-
grams that allow them to make a profit
from such wetland products. Careful man-
agement of wetlands allows some land-
owners to use them for aquaculture to
raise food organisms, such as crayfish,
carp, or bullfrogs, and bait fishes, such as
minnows.
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Hunting and Trapping
Two of the most common recreational
uses of wetlands are hunting and trap-
ping. Hunting of ducks and geese and
other species that are found in wetlands is
enjoyed by millions of people every year.
Without wetlands much of this hunting
would cease to exist. On the other hand,
without hunting many wetlands that are
now preserved by waterfowl hunting clubs
would be lost to drainage. Hunters also
preserve wetlands through their purchase
of hunting licenses and Migratory Bird
Hunting and Conservation Stamps ("duck
stamps") since these funds are partly
used for the purchase of wetland areas.
Hunters are also the primary source of the
income that state wildlife agencies use to
preserve and manage wetlands. Proper
management of wetlands results in
increased game production and an
increase in recreational opportunity. Many
landowners derive added income from
their wetland areas by annually leasing
the hunting rights to waterfowl hunters. In
some areas of the United States farmers
may make more profit by leasing hunting
rights than by raising crops.
Furtrapping in wetlands is a multi-
million dollar industry in the United States.
Trappers in numerous states harvest hun-
dreds of thousands of muskrats, mink,
raccoon, beaver, nutria, and other wet-
land furbearers every year. These mam-
mals are a valuable wetland resource that
responds well to proper management and
utilization. Individual landowners often
lease their wetlands for fur harvest either
by direct cash payment or by shares con-
sisting of a percentage of the fur harvest
value. Other wetland owners may wish to
trap these animals themselves so they
may enjoy not only the profit but also the
recreation. Although fur harvest in U.S.
wetlands is big business, there are rela-
tively few professional trappers compared
to the many people who trap primarily for
recreation.
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Aesthetic Values
The non-consumptive users of wetlands
have greatly increased in recent years.
Historically hunters and trappers were the
primary users of wetlands, but today there
are many birdwatchers, students and
teachers, artists, cross country skiers, and
other persons who regularly visit wet-
lands. Some federal, state, county, city,
and even private wetlands are now set
aside strictly for nature study and non-
consumptive uses. In such areas visitors
are often accommodated with board-
walks and other conveniences that pro-
vide easy access. This type of use
requires a different form of management
than most landowners are concerned
with. Individual landowners can some-
times make a profit by selling or leasing a
wetland to an agency or organization for
such use.
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Agricultural Values
There are many agricultural uses of wet-
lands and, properly managed, a wetland
may yield many things to a farmer. One of
the most obvious uses is the grazing or
haying of wetland vegetation. In many
parts of the U.S. farmers have grown to
depend on the hay crops that wetlands
can provide annually. Such hay crops are
especially important in those areas where
periodic drought causes upland crop fail-
ures. In drought years the wetland basin
may be the only part of the farm that
produces a harvestable crop. And in nor-
mal years a farmer can almost always
take a hay crop from the edge of the
wetland as natural drying occurs during
the summer.
In some situations, farmers have
taken advantage of their wetlands by sow-
ing native wetland grass seeds for later
harvest. Such management techniques
are not yet well established, but many
farmers have successfully changed the
plant composition of their marshes so that
they have increased yields. Caution must
be exercised in harvesting wetland plants
since continual use could result in unde-
sirable changes in plant composition.
Many wetland plants have high nutri-
tional values and in some areas of the
country, such as Florida, these wetland
plants are recognized as some of the best
available forage. Most marsh grasses,
sedges, and rushes are as good as or
even better than Kentucky bluegrass for
livestock grazing or hay production. In
freshwater marshes, common reed, reed
canary grass, maidencane, and some of
the cutgrasses are nutritious for cattle.
Salt marshes and brackish marshes also
provide a variety of plants, such as the
cordgrasses, that are suitable for live-
stock. Even some of the coarser marsh
plants, such as cattails and bulrushes, are
nutritious early in the growing season.
Harvesting of hay from wetlands or direct

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Values to Society
grazing of wetlands can be a viable alter-
native to draining and attempting to grow
row crops.
Farmers receive several other direct
benefits from wetlands. Wetlands provide
catch basins to hold water in the fields so
it will soak in and provide increased soil
moisture. Some wetlands may help to
recharge local wells on individual farms
and they certainly provide a source of
water for livestock. Wetlands modify the
atmosphere in their immediate vicinity and
may provide a better growing environment
for crops on adjacent uplands. Wetlands
also help to trap sediment runoff from
plowed ground and thereby control on-
farm pollution of water supplies and help
to protect ponds and streams.
Wetlands have numerous values that
benefit society at large, but have only
questionable direct value to the individual
landowner. In some areas of the U.S.,
groundwater may be wholly or partly con-
trolled by wetland water regimes. There is
no doubt that society benefits from the
water pollution control values of wetlands.
Many wetland plants are efficient at
removing nutrients from water and a few
will even remove harsh contaminants,
such as mercury and other metals. Some
cities and industries are even beginning to
use natural or man-made marshes as part
of their sewage treatment process. Wet-
lands also serve as sites for recycling and
trapping nutrients, such as phosphorus,
that otherwise would be lost to our rivers
and eventually the oceans. All of these
nutrient and pollution control values help
to prevent the contamination of our rivers,
lakes, and groundwater.
When wetlands are abundant in an
area they can help to prevent floods or to
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lessen their impact on downstream areas,
A large number of wetlands can store a
considerable amount of rainfall and delay
its runoff. This storage and delay can
prevent minor floods or lower the peak
depths of major floods in downstream
areas. Widespread drainage in an area
can have the opposite effect and result in
increased flooding problems.
Wetlands also have major educa-
tional and scientific values. Regardless of
their size, individual wetlands can provide
outdoor classrooms where teachers can
demonstrate the workings of nature to
their students. Because of their values to
society, wetlands also provide unique lab-
oratories where scientists can learn new
and useful things that can provide many
benefits.
When a wetland is drained or filled,
the effects are obvious. But sometimes
the effects of lesser actions are not so
obvious. Partial filling or draining, or deep-
ening by dredging or dam construction
can result in minor changes in the wetland
and subsequent loss of some of the desir-
able values. Manipulation of the water-
shed or intensive use of groundwater can
also drastically influence a wetland. Redi-
rection of surface flows might eventually
result in a reduction of the size of a
wetland and over utilization of ground-
water in an area often results in the com-
plete elimination of a wetland. However, it
is possible to enhance the values of your
wetland by proper management. The fol-
lowing pages briefly describe a few man-
agement alternatives that will help
landowners receive an economic return
from their wetlands and preserve and
enhance these natural values.
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Wetland Management
Wetlands are a product of the surrounding
landscape. As that landscape changes,
the wetland itself will also change. Proper
management techniques can be used to
help maintain the "naturalness" of a wet-
land even when the surrounding land is
changed. With reasonable planning and
investment, management can also
enhance or improve the productivity of a
wetland.
Some wetlands are among the most
productive habitats in the world. An aver-
age marsh will usually produce an annual
biomass that is several times as great as
that of adjacent uplands or croplands. Of
course, much of this production is not
directly utilized by man, but the high pro-
ductivity does produce a variety of things
that humans use.
Wetlands are very diverse ecosys-
tems. They support many different kinds
of plants and animals. One of the reasons
for this diversity and overall high produc-
tivity is the fluctuating and dynamic nature
of most wetlands. Some wetland types,
such as prairie potholes, go through cyclic
changes from very wet to very dry
depending on the climate. Many wetlands
have annual drying cycles with periods of
high water levels followed by short- or
long-term drying cycles. These normal
water changes allow many different kinds
of plants and animals to find living space
in wetlands. These changes in water lev-
els also make wetlands management a
real challenge since you can't always plan
for changes in climatic patterns.
One of the possible goals of manage-
ment might be to simulate such cycles by
water management. By modifying water
levels and providing a diversity of habitat
types you can increase the natural pro-
ductivity of many wetlands. Fully under-
standing the results of such management
can allow you to produce an abundance
of one or more kinds of desirable animals,
such as ducks.
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Waterfowl Production
Increasing the production of certain types
of waterfowl may be economically feasi-
ble and relatively easy for some landown-
ers. The best method of increasing
waterfowl production on your wetlands is
by providing nearby upland nesting cover.
In much of the north central U.S. this may
be done by leaving upland blocks of
undisturbed native grasses or by convert-
ing cropland into dense nesting cover by
planting a mixture of legumes and grasses
and leaving them undisturbed for 4 to 7
years. In areas of the southern U.S. where
wood ducks are the primary nesting spe-
cies, large hardwood trees, especially hol-
low snags, are necessary for natural
nesting sites. Such trees should be pro-
tected if maximum waterfowl production is
your goal. Duck and goose production
may also be increased by providing artifi-
cial nest sites.
Some types of ducks, such as wood
ducks, will readily accept artificial nesting
boxes. Such boxes may be hidden in
nearby trees or placed on stakes in the
open water. Other types of ducks will
sometimes nest in basket-like structures
placed on poles over the water. Ducks
that do nest in such boxes or baskets are
easy targets for predators and you should
always place a barrier on the nest box
pole to prevent predators from reaching
the nest. Whenever possible, artificial
nest structures should be placed in small
openings in the marsh or swamp vegeta-
tion. The vegetation will help protect the
structure from wind, wave, and ice action.
Artificial nest structures can be easily po-
sitioned during the winter in northern
areas since the marsh will be frozen.
Nesting material, such as wild hay or
straw, should be added to the structure
well before the beginning of the nesting
season and the box or basket should be
cleaned out each winter. Your local wild-
life conservation officer or biologist can
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give you helpful hints on building and
erecting nesting structures.
If Canada geese occur in your area,
they can be attracted to your marsh by the
addition of an appropriate nesting struc-
ture. Almost any large tub or platform will
be usable by geese. The best structures
provide raised sides with side bars for the
adults to use. If the structure has a solid
bottom, drainage holes should be added.
Nesting material should also be added
and changed each year. In some parts of
the country large bales of straw (such as
flax straw) are readily available for use as
nesting structures. These may be placed
on the ice in the winter and allowed to
settle to the marsh bottom to provide an
artificial "island" for nesting geese and
ducks. The bale should be securely
wrapped with extra-strong wire to make it
last and it should be placed in water that
allows about half of the bale to be above
the surface.
One of the most effective methods of
producing more waterfowl and other
marsh birds is by creating one or more
small islands in your wetland. Small
islands may be created by a minor dredge
and fill operation. When wetlands are dry
a small bulldozer or even a tractor with
backhoe or scraper blade will be suitable
for creating islands. Using fill material
from the wetland will allow you to create
open areas that will also benefit water-
fowl. Islands that are placed in large wet-
lands must be carefully located since they
are very subject to wave erosion. In large,
open wetlands lining the edges of islands
with rock riprap will help to prevent such
erosion. Professional guidance on island
construction and location is a must if you
are to successfully meet your manage-
ment goals. In most cases, island con-
struction in a wetland will require one or
more local, state, or federal permits.
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Managing Water
The management of a wetland usually
means controlling the amount of water on
a wetland and the skilled manipulation of
that water. Various techniques have been
developed to manipulate water. The
methods usually involve diking, pumping,
dredging, or control of flows. When these
techniques are properly used they can
create a beautiful, natural-appearing wet-
land. If they are used improperly and with
no understanding of the consequences of
their use you may end up accidently
destroying many of the values that you
wanted to enhance. In most States .there
are land managers who are skilled in wet-
lands manipulation. If you decide to initi-
ate any of the forms of wetland
management described on the next few
pages you should discuss your manage-
ment goals and plans with one of these
skilled managers. A small amount of time
invested in proper planning before you
begin could save you thousands of dollars
and mean the difference between sucess
or failure in your management plan.
Manipulating water levels in a marsh
is one of the best management tools we
have. Such manipulation attempts to sim-
ulate natural cycles to produce desirable
stands of wetland plants. When water is
removed from a marsh, many seeds ger-
minate to produce stands of plants that
cannot germinate during periods of high
water. As these plants grow older, they
can tolerate certain amounts of water.
The marsh manager takes advantage of
this and gradually refloods the marsh to
create a desirable interspersion or mixing
of plants and water.
The process of removing water from
a marsh, allowing plant germination, and
reflooding is termed "drawdown" by wet-
land managers. Drawdowns usually result
in an improvement in soil fertility by
increased availability of plant nutrients
and aeration of the waterlogged soil. This
is an important step in rejuvenating the
marsh.
Drawdowns can encourage the ger-
mination and establishment of a large
number of emergent plants, such as bul-
rushes, cattails, and various grasses.
Short-term drawdowns of a few weeks
will encourage herbaceous plants, while
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longer drawdowns may allow woody
cover, such as willows, to become estab-
lished. Annual seed plants can be encour-
aged by annual, partial drawdowns. The
timing of annual drawdowns is very impor-
tant in determining what species of plants
germinate and grow. Maintaining good
growths of aquatic food plants, such as
sago pondweed, is more difficult and nor-
mally requires very careful water manage-
ment over a period of several years. The
timing of a drawdown is also important
since you may adversely affect some
marsh animals during their breeding
season.
Water management may also be
used to create open water areas in
marshes that are overgrown with exces-
sive vegetation. Spring flooding and
gradual lowering of water levels over the
main growing period can result in the
thinning of the vegetation to create better
wildlife habitat. Flooding a marsh for one
or more entire growing seasons may be
necessary to open some dense stands of
cattail or to thin an overabundance of
woody vegetation.
Water level management can also be
used to influence the type of wildlife and
fish use that occurs on a wetland. Lower-
ing water levels may help to control popu-
lations of rough fish, such as carp. On the
other hand, increasing water depths in the
spring may provide spawning habitat for
other fish, such as northern pike. In north-
ern areas increasing water level in the fall
and winter may be necessary to insure
that muskrats have sufficient water to
continue their activities below the ice.
In general, the management of water
levels in a wetland is done to produce a
diversity of habitat for wildlife and a good
interspersion of open water and vegeta-
tive cover.
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Dredging, Diking, and Ditching
Dredging and diking are usually necessary
in order to create new wetlands or to
begin controlling the water levels in an
existing wetland. This technique is usually
expensive, but it is also usually the only
reasonable method for gaining control of
water levels. In some instances a marsh
may have limited inflow or outflow chan-
nels and it will be possible to use a very
limited amount of diking to control the
entire wetland. In extensive marsh sys-
tems a large amount of diking will be
necessary. In some cases a very low dike
can be created with readily available farm
implements.
Carefully planned diking may be used
to create a new marsh by flooding former
upland or it may be used to expand the
size of an existing marsh. Diking com-
bined with water level control will allow
the creation of the most favorable and
productive marsh.
Blasting has sometimes been used to
create ditch systems, but this method
leaves spoil banks that are very suscepti-
ble to wind and wave erosion. Dragline
ditching leaves spoil banks that, when
properly deposited, leave a chain of
islands that serve as nesting sites for
waterfowl, den sites for muskrats, and
habitat for a wide variety of other marsh
animals.
Level ditching is a method of creating
open water and a series of islands in large
marshes. Draglines or bulldozers may be
used for this purpose. The dredging
increases habitat variety by providing
open water and dry areas for nesting and
den sites. Level ditching has been shown
to increase furbearer and waterfowl pro-
duction significantly on some marshes.
The ditch systems also allow boat access
to the marsh during hunting and trapping
seasons. Level ditching is useful primarily
on very large marsh systems. In small
marshes the technique may result in irrep-
arable damage to the wetland ecosystem.
This technique is fairly expensive and it
should not be undertaken without sound
guidance from professional biologists and
engineers. The use of this technique will
require various state or federal permits.
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Water Control
Many water-level control devices have
been developed. A few of these are
pictured in this booklet. The most simple
devices take advantage of natural water
flows by retaining runoff at set levels or by
allowing water to flow only into or out of a
wetland rather than both in and out.
These simple devices may be sufficient to
maintain your wetland. Your local soil
conservationist or biologist can help you
obtain these devices and make
recommendations on their installation.
More complicated wetlands manage-
ment will require the ability to add or
remove water as necessary. Such water
management means pumping water into
or out of a wetland. The pumping system
may consist of a complex series of chan-
nels, dikes, dams, and pump stations or it
may be only a mobile pump operated by a
tractor or small gasoline engine. In a few
cases groundwater pumped from wells
has been used to provide the necessary
water.
Before you begin a management pro-
gram of manipulating water levels be sure
that you have a legal right to do so. Water
rights laws vary greatly from state to state
and before you begin a water manage-
ment program it may be necessary for you
to apply for water use or disposal permits.
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Other Management
Several other forms of wetlands manage-
ment may be useful under some condi-
tions. These techniques include grazing,
burning, mowing, and other forms of vege-
tation manipulation. Grazing by cattle can
be used to open dense stands of vegeta-
tion. If grazing is done it is best used
heavily and in the early part of the growing
season. Removal of the cattle before the
midpoint of the growing season will allow
several valuable waterfowl plants to com-
plete their growth. Excessive grazing
should be avoided.
Muskrats can also be important in
opening dense stands of marsh vegeta-
tion. Muskrat populations can be built up
by partial protection for one or two years.
During this time trapping should be light.
As the population increases the muskrats
will create extensive openings in the
vegetation. If muskrat populations are
allowed to build up they should be heavily
trapped in following years to prevent over-
population and degradation of the habitat.
Burning can be useful in managing
some wetlands for ducks, geese, and
muskrats. Fire is used to eliminate exces-
sive growths of vegetation that are not
very useful to wildlife. It also releases
nutrients and results in new plant growth
that provides food and nesting cover for
ducks, geese, shorebirds, and marsh
song birds. The burning of wetlands
should be used with caution since it is
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possible to severely damage some wet-
land ecosystems by this technique.
Before you do any burning you should
check local laws to determine if a permit
is required.
Mowing is sometimes used to open
dense stands of wetlands vegetation. This
may be done to attract wildlife or to pro-
vide more variety in habitat types. Under
some conditions herbicides may also be
used, but such use is not recommended.
The techniques used in wetlands
management often have two sides. Used
in moderation and with common sense
they can provide significant benefits, but
used improperly they can be destructive
to the values you are trying to enhance.
In many cases, the best management
may be no management at all. Simple
protection from grazing animals and
excessive human use will allow some wet-
lands to remain in a natural, productive
condition. If you are happy with your wet-
land area, don't make any drastic
changes without seeking professional
advice, so you don't accidentally destroy
what you already have.
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Preserving Your Wetland
Landowners who wish to preserve their
wetlands will find some private, local,
state, or federal programs that may apply
to their land. These programs may involve
incentive payments, easements or out-
right purchases, leases, or tax relief.
Private programs might include leas-
ing or selling your wetland to an organiza-
tion such as a private hunting club, a local
conservation club, or a national group
designed to protect unique areas, such as
The Nature Convervancy. If you wish to
permanently preserve your wetland you
may decide to give it to a non-profit orga-
nization, such as a university or a local or
national conservation group such as the
National Audubon Society. Such a gift
could provide you or your heirs with sig-
nificant tax deductions.
If you wish to retain your wetlands
property, yet protect it forever, you could
enter a clause in your property deed that
would forbid any future owner from drain-
ing or otherwise destroying the wetland.
Some states, such as Minnesota,
provide significant tax relief to landowners
who preserve their wetlands. These
deductions or other forms of tax relief
are given as an incentive for wetlands
protection.
Most states and some county govern-
ments have land acquisition programs
that protect natural areas, such as wet-
lands. A few will also buy conservation
easements that protect wetlands. Selling
your wetland to a state or local govern-
ment will provide protection of that land.
Various agencies of the federal gov-
ernment have programs that are designed
to assist private landowners in protecting
wetlands. In many cases, these programs
pay the landowner. Some of these pro-
grams, such as the U.S. Department of
Agriculture's Waterbank Program, provide
short-term protection of a few years for
wetlands. Others, such as the U.S. Fish
and Wildlife Service's Small Wetlands
Program, provide for perpetual easements
that will preserve the wetland without
taking away many of the landowners'
rights to farm or otherwise use the natural
wetland. The U.S. Fish and Wildlife Serv-
ice also purchases wetlands for waterfowl
production or as part of the National Wild-
life Refuge System in some parts of the
United States.

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For More Information And
Assistance
This bulletin provides only very brief dis-
cussions of wetlands management tech-
niques. Since some techniques are more
useful in some parts of the country than
others you may wish to seek more
detailed advice on wetlands management
from local agencies. Numerous agencies
and private organizations can provide
you with more information or technical
assistance.
Private organizations to contact
would include local private hunting club
managers, the National Wildlife Feder-
ation and its 50 state affiliates and
thousands of local clubs, The Nature Con-
servancy, and local chapters of the
National Audubon Society. Addresses of
these and other private organizations can
be obtained from your local offices of the
agencies mentioned below.
Technical assistance in wetlands
management in your county can be ob-
tained from your county Soil Conservation
Service or Agricultural Stabilization and
Conservation Service office or from a
local state wildlife agency office or
representative.
State agencies that can give you
information or assistance on wetlands
management would include the state wild-
life department, some natural resource
departments, university wildlife depart-
ments, or offices of the extension service.
Depending on your location you may
be able to obtain information and techni-
cal assistance on wetlands management
from the U.S. Fish and Wildlife Service,
the U.S. Environmental Protection Agen-
cy, or from a local office of the U.S. Soil
Conservation Service.
Photographs by:
Dave Beck, page 22.
G.E. Mann, U.S. Fish and Wildlife
Service, page 15.
U.S. Fish and Wildlife Service,
South Dakota Cooperative
Wildlife Research Unit, all others.

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