&EPA
United States
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Environmental Protecting WellamiS JOT
Protection Agency
Wetlands are important elements of a watershed because they serve as the
vital link between land and water resources. Wetlands play an integral role in the
ecology of a watershed. Their shallow waters, nutrients, and primary
productivity are ideal for organisms that form the base of the food web upon
which many species of wildlife depend. Wetland habitat provides the necessary
food, water and shelter for mammals and migrating birds. Other animals, such
as amphibians and reptiles, collectively known as herpetofauna, or "herps,"
depend on wetlands for all or part of their life cycle, meaning that their survival
is directly linked to the presence and condition of wetlands.
Amphibians and Reptiles
Depend on Wetlands
Wetlands serve as critical habitat for
many species of amphibians and
reptiles. Most amphibians lay gelatinous eggs
under water, while others, like certain
salamanders, lay their eggs on moist land. After
the eggs hatch, the baby amphibians enter an
aquatic larval stage, which can last from several
days to many months. Once the aquatic stage is
completed, the amphibians leave the water and
enter the terrestrial adult stage of life. Wetlands
serve as breeding sites, as a habitat for larval
development and as a primary food source for
adults. Insects, spiders, snails, worms and
small fish are all prey for certain amphibians.
For many reptiles,
wetlands also serve
as primary habitat,
supplying them with
an ample source of
food and habitat for
breeding and
nursing. Specially
adapted reptiles that
are able swimmers
are likely to be
found in wetlands.
Some of these
include the common
snapping turtle,
spotted turtle,
northern water
snake, cottonmouth
snake, diamondback
water snake and
garter snakes.
Amphibians and reptiles depend upon a variety
of wetland types. These may include marshes,
swamps, bogs and fens (and their associated
subclasses). Some wetlands are only wet a
portion of the year and are considered
"ephemeral" wetlands. These wetlands provide
important habitat and breeding grounds (see
side bar).
There are often strong ecological connections
among wetlands in a landscape. Although some
may be permanent and others ephemeral,
amphibian populations can depend on multiple
wetlands within a given area. To protect these
species over the long term, the variety and
density of suitable habitat sites within the
landscape must be preserved, along with
terrestrial corridors that connect the wetlands.
Garter Snake (Thamnophis elegans) - When disturbed, garter snakes will release
an unpleasant smelling musk from glands located at the base of their tail.
Why are
ephemeral
wetlands
important?
Vernal pools, one
type of ephemeral
wetland, are of
critical importance
to amphibian
populations. As
small, often
isolated wetlands,
vernal pools are
only wet for a
portion of the
year. Periodic
drying creates a
fish-free
environment for
amphibians, many
of which have
adapted rapid egg
and larval stages
as a race against
the dry season.
The absence of fish
predators in
vernal pools
benefits
amphibian
populations.
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Threats to Herps and Wetlands
The American toad (Bufo americanus) is one of the most commonly heard
frog or toad species in the United States. The male toad's call is a long,
uninterrupted 15-20 second trill that can be heard over a long distance.
Wetland Habitat Loss
Over 220 million acres of wetlands are thought to have existed in the lower 48 states prior to 1700.
Since then, extensive losses have occurred, and over half of our original wetlands have been drained
and converted to other uses. Though the rate of loss has decreased in recent decades, wetlands and
other aquatic resources are still threatened by activities such as ditching, draining, dredging and
stream channelization; deposition of fill material for commercial and residential development,
dikes, levees and dams; crop production, logging and mining. Since many amphibian species need
both aquatic and terrestrial habitat, it is very important to preserve wetlands and a buffer strip of
adequate upland habitat.
In order to maintain healthy amphibian and
reptile populations, wetland habitat must be
protected. A watershed contains multiple
habitats, all of which are affected by changes
in hydrology, land use and water quality.
Since no habitat is isolated from its
surroundings, protection ofherps must take
place at both the large-scale watershed level
and at the smaller scale of individual
wetlands.
Population declines and disappearances of
amphibians and reptiles leading to widespread
scientific and public concern have been well
documented. The causes for their decline,
while not fully understood, appear to be
complex and numerous.
47 of the 60
reptile
species found
in Illinois
rely upon
wetlands
Why are
amphibians so
vulnerable?
Some amphibians
breathe through their
porous skin, which
makes them extremely
vulnerable to pollution
in the soil, air, and
water. You can think of
amphibians as sponges
that soak up their
surrounding
environment. This is
why you shouldn't try to
catch frogs if you have
insect repellent on-the
toxic repellent will seep
into their skin and harm
them.
Chemical Pollution
Due to their amphibious lifestyles, herpetofauna are very sensitive to changes in the water and
surrounding land. Many synthetic organic compounds and metals adversely affect amphibians and
reptiles. Sublethal effects of chemical pollutants can impair a herp's ability to swim, catch food and
reproduce successfully. Amphibians are particularly sensitive to chemical contaminants owing to
their permeable eggs and skin. A recent study by the U.S. Geological Survey (USGS) showed that
"organophosphorus pesticides from agricultural areas, which are transported to the Sierra Nevada on
prevailing summer winds, may be affecting populations of amphibians that breed in mountain ponds
and streams." The scientists estimate that
damage could be even worse for those species
more closely associated with water.
Endocrine disrupting chemicals (EDC) have
been of great concern in the amphibian and
reptile community. Studies have shown that
chemicals like polychlorinated biphenyls (PCBs)
build up in turtle eggs, reduce eggshell
thickness and cause reproductive failure. Other
studies have shown reduced male organ size
among reptiles, which results in difficult sex
recognition and the subsequent lack of
reproduction. Both amphibians and reptiles are
very susceptible to the dangers of EDCs.
Marbled Salamander (Abystoma opacum) -
Courtship begins when the male nudges the
female with his snout.
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Nutrient Loading
The indirect effects of excess nutrients can be
very detrimental to amphibians. Nutrients
such as nitrogen and phosphorous can cause
dominance of algae, which is not conducive to
laying eggs. Excess nutrients can also reduce
the amount of oxygen available in the water for
amphibian tadpoles and alter the composition
and numbers of the invertebrate communities
that are food for the juveniles. In Texas, playa
wetlands receiving nutrient-laden feedlot
effluent were devoid of amphibians found in
natural wetlands. In this case, experiments
indicated that the nutrient concentrated effluent
had to be reduced to less than 3% of its
original strength in order to minimize adverse
effects.
Some turtles, such as the
diamondback terrapin, are
endangered owing to commercial
harvesting, stemming primarily from
the food industry.
The pet trade also endangers many
reptiles, such as the box turtle.
Eastern Gray Treefrog (Hyla versicolor) - Its call is a
resonant, flutelike trill similiar to the call of the
red-bellied woodpecker. Depending upon its
environment, this treefrog can range in color from
bright green to gray. They breed in permanent to
semi-permanent wetlands.
On the whole, it is difficult to document
reptile population trends. Many species
have secretive natures, which, when
combined with large home ranges, low
population densities and a rarity of
congregational behavior, may result in a
severe population decline without being
noticed by people.
American Crocodile (Crocodylus acutus) - Once hunted intensively for their
hides, today poaching and the loss of habitat to human development are the
greatest threats faced by American crocodiles.
Additional Threats
Global climate change may threaten aquatic and
semiaquatic life by reducing wetland acreage due to
frequency and severity of storms and sea level rise.
Latitudinal shifts in temperature and precipitation
patterns also threaten herps.
Ozone depletion causes an increase in the amount of
Ultraviolet radiation that reaches the earth's surface and
waters. Research has shown that UV-B radiation has
adverse effects on some amphibians. The Montreal
Protocol has reduced emissions of ozone-depleting
chemicals.
Invasive species pose a constant threat to native herps.
Invasive plants and animals can alter the ecological
community that is relied upon by native reptiles and
amphibians. Invasive herpetofauna can also directly
damage native populations. In many parts of the U.S.,
invading bullfrogs are preying on and often eliminating
other amphibians, as well as impacting some reptiles and
fish.
Disease and Parasites significantly contribute to
declining amphibian and reptile populations. To help
prevent the spread of disease and parasites, follow
careful washing procedures when traveling between
wetlands.
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Conservation Efforts for Amphibians and Reptiles
Conservation efforts for amphibians and reptiles come in many different
forms. Like other wildlife conservation efforts, the first step is to identify
and monitor existing populations. The USGS has a volunteer monitoring
program where participants learn to identify local frog calls and submit
observational data at different times of the year.
Fortunately, laws are being passed in some States to protect herpetofauna.
New Jersey adopted special protections for vernal pools to ensure
sufficient regulatory review. California enforces laws to prevent people
from taking native reptiles and amphibians without a license, except
common herp species. The laws also forbid the sale of herpetofauna for
human consumption. Various bird and wetland initiatives have positive
impacts on herps as well.
The North American Wetlands Conservation Act (NAWCA), a habitat-
oriented program led by the U.S. Fish and Wildlfe Service, has been
particularly helpful to amphibians and reptiles, as waterfowl and herpeto-
fauna often share the same habitat. The conservation programs within
the U.S. Department of Agriculture's Farm Bill program also help to
preserve or restore habitat for herpetofauna.
The chicken turtle (Deirochelys reticularia) is found
in the southeastern United States from southeast
Virginia to east Texas. Their preferred habitat
includes quiet bodies of water such as ponds,
swamps, and marshes. Although an aquatic
species, it readily wanders and is often found out
of water. They are mainly carnivorous, and their
diet includes tadpoles and crayfish.
Tfow Czti Ycm Tfclp?
You can help to save amphibian and reptile diversity in many different
ways. On a larger scale, working to protect your watershed is the first
step to ensuring clean water and healthy habitat for herps. You should:
• Prevent soil erosion by seeding for grass or planting shrubs;
• Avoid dumping chemicals down drains;
• Maintain vegetative buffer strips between your land and any surface
waterbody; and
• Avoid releasing or transporting exotic plant or animal species into
the environment.
Protecting surface water and wetlands is important to promoting herp
diversity. Identfying, monitoring and restoring local wetlands are great
ways to educate yourself and your community about the important
functions and values of wetlands. Supporting public and private
organizations involved in habitat protection is another way to help.
Further information can be found at http://www.epa.gov/owow/wetlands/
vital/protection.
PARC - Partners in Amphibian and
Reptile Conservation
Partners in Amphibian and Reptile
Conservation (PARC) is the largest
herpetological conservation partnership in the
nation. They are a habitat-focused partnership
involving State agencies, Federal agencies, the
private sector, conservation organizations, and
the academic community. The partnership is
dedicated to
protecting endangered
reptile and amphibian
species and keeping
common native
species common.
Their website
(www.parcplace.org)
contains educational
materials on the
conservation of amphibians and reptiles along
with an extensive list of weblinks.
EPA843-F-03-015
Office of Water
On the Internet
Partners for Amphibian and Reptile Conservation www.parcplace.org
U.S. Environmental Protection Agency www.epa.gov/owow/wetlands
U.S. Geological Society www.usgs.gov/amphibians
U.S. Fish and Wildlife Service www.wetlands.fws.gov
USDA Natural Resources Conservation Service www.nrcs.usda.gov/programs/wrp
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