Reptiles and Amphibians at
Blackwater National Wildlife Refuge:
The vast marshes and bordering swamps which comprise
Blackwater
National Wildlife Refuge offer ideal living conditions for an array of
reptiles and amphibians. Some of these creatures are often easily
observed, such as a painted turtle basking on a log on a summer's day,
but most are shy and elusive, well camouflaged in their environment.
Some
are nocturnal (active mainly at night). These cold-blooded animals
become dormat with the onset of winter. But with spring's return,
the Refuge wetlands come alive with the sound of frogs and toads, and
with
the activities of turtles, snakes, and salamanders. Through the long
summer nights the deep bass voice of the bullfrog resounds. By both
day and night water snakes ripple the surface waters and rat snakes
hunt
in the woodlands; turtles appear on the roads during their wanderings;
toads are conspicuous throughout the drier areas. All of these animals,
from the smallest salamander to the largest snapping turtle, are
important
to the ecosystem of Blackwater. Many reptiles and amphibians feed
on insects, others on rodents, and most, in turn, are fed upon by
raccoons,
egrets, or a host of other animals. But whether predator or prey,
they all contribute to the rich assortment of wildlife which makes
Blackwater
so unique. All reptiles and amphibians are protected on the refuge and
may not be collected or killed. Reptiles include turtles, snakes,
and lizards and are characterized by bodies with dry skin (not slimy),
and usually with scales or scutes.
Turtles
Snapping Turtle
Chelydra serpentina
A large, common turtle in freshwater ponds and marsh; also inhabits
brackish marsh. Aggressive on land, seldom so in water. Lays
eggs in upland areas in late spring. Omnivorous- feeds on vegetation
as well as small animals, young waterfowl, and carrion.
Stinkpot
Sternotherus odoratus
Aquatic, bottom-loving species found in freshwater areas. Avoids
brackish waters. Named for a musky secretion exuded when handled.
Eastern Mud Turtle
Kinosternon subrubrum
A good swimmer. Another bottom-loving turtle, though likes land.
Found in brackish marsh as well as freshwater. More common than
skinkpot
which it resembles.
Spotted Turtle
Clemmys guttata
Inhabits shallow freshwater areas. Common; most frequently observed
in spring, when it is often seen on roads. Likes to bask. Not
aggressive.
| Spotted Turtle |
 |
| These turtles, also known
as "polka dot" turtles,
are seen most often in the
spring. They tend to prefer
shallow bodies of water
and can be found in and
around small ponds or
roadside ditches. Younger
turtles usually have only
one spot per scute or scale
on their shell, while older
turtles, like the one pictured
above, will have a more
scattered pattern of a hundred or more dots. |
Eastern Box Turtle
Terrapene carolina
A dry-land turtle most frequently seen in the woodlands. A slow
and deliberate mover. Omnivorous- feeds on fruits and other pland
materials as well as small animals. Can live for 40 years or more.
Northern Diamondback Terrapin
Malaclemys terrapin
An aquatic turtle of salt marsh and brackish water habitats.
Likes to bask. Feeds on fish, crustaceans, mollusks, and insects.
Lays eggs on dikes and uplands in early summer.
| Diamondback Terrapin |
 |
| Terrapins have a beautifully
ridged shell and speckled
face. The brown line that runs
along their face has caused
people to comment on the
turtle's unusual smile! The word
"terrapin" is actually derived from
a french word meaning "soup turtle,"
which is what these turtles were
trapped for. Today terrapin soup
can still be found on the menu
occasionally in smaller
Eastern Shore towns. |
Red-bellied Turtle
Chrysemys rubriventris
Uncommon. Prefers larger bodies of fresh water. Basks like
the painted turtle but is much larger. Largely vegetarian.
Eastern Painted Turtle
Chrysemys picta
The most conspicuous turtle on the Refuge. Can be seen
throughout the summer and into the autumn basking in the sun on logs or
stumps in the freshwater pools and brackish marsh. An excellent swimmer
although it may wander far from water. Feeds on aquatic vegetation,
insects, and other small animals.
| Basking Painted Turtles |
 |
| At Blackwater, this is
a familiar scene.
Turtles will often pull
themselves up onto logs
and rocks to warm up.
Turtles are cold blooded,
like most reptiles, and use
the heat from the sun to
regulate their body
temperatures. |
Lizards and Skinks
Northern Fence Lizard
Sceloporus undulatus hyacinthinus
Favorite habitats are rotting stumps and logs. Arboreal (climbs
trees). Feeds on insects and other invertebrates.
Ground Skink
Leiolopisma laterale
As name implies, this skink is ground dwelling and seldom climbs.
Will enter shallow water to escape. Insectivorous (feeds largely
on insects).
Five-lined Skink
Eumeces fasciatus
Mainly ground dwelling but may occasionally climb trees. Prefers
cutover woodlands with many rotting stumps or logs. Habitat usually
damp. Insectivorous.
Broad-headed Skink
Eumeces laticeps
A large woodland skink. The most arboreal of the skinks.
Snakes
Red-bellied Water Snake
Nattrix erythrogaster
Very common. Aquatic, though often wanders well away from water in
hot, humid weather. Both water snakes like to bask on logs or brush
and are adept at swimming and diving.
Northern Water Snake
Natrix sipedon
Common throughout the more freshwater wetlands of the Refuge.
Obtains food, including frogs, salamanders, and small fish, in or near
water. Both water snakes, though harmless, are sometimes mistaken
for the venonmous water moccasin, which does not occur in Maryland.
| Northern Water Snake |
 |
| This is the only large water
snake in most of the northeast,
with a record length of 55 inches.
These snakes are found usually in
slow moving, placid water areas,
but have also been known to
populate flowing river areas, as
well. Water snakes, although not
venomous, do have a nasty bite.
They have what is known as an
"aseptic" mouth, basically
meaning that their mouth is a haven
for bacteria and a bite is a sure
recipe for infection if not
treated appropriately. These
snakes are not aggressive, but
will bite if provoked. |
Eastern Garter Snake
Thamnophis sirtalis
Common throughout fields, woods, and marsh edge habitats. Feeds
on small animals from earthworms to frogs.
Eastern Ribbon Snake
Thamnophis sauritus
Semi-aquatic, seldom far from marsh or pons. Prefers shallow
water, swimming at the surface instead of diving as water snakes do.
Eats salamanders, frogs, and small fishes.
Eastern Hognose Snake
Heterodon platyrhinos
Prefers sandy areas. Feeds mainly on toads; also eats frogs,
tadpoles, and insects.
Ringneck Snake
Diadophis punctatus
Secretive. Found under logs, loose bark of dead trees in most habitats.
Prey includes earthworms and other small salamanders, lizards, and
snakes.
Eastern Worm Snake
Carphophis amoenus
Likes moist earth. Usually found under logs, boards, or other debris.
Northern Black Racer
Coluber constrictor
An active snake. Feeds on rodents, small birds, other snakes,
frogs, and insects. Diurnal- active by day.
Rough Green Snake
Opheodrys aestivus
Semi-aquatic and an excellent climber. Food consists of spiders,
small insects and their larvae.
Corn Snake
Elaphe guttata
Climbs well, though mainly terrestrial, spending much time underground.
Kills mice, young rats, and small birds by constriction; young corn
snakes
eat mostly frogs.
Black Rat Snake
Elaphe obsoleta
A common large snake. Usually seen on the ground though an excellent
climber. Kills its prey by constriction. Feeds on birds, eggs, and
mice.
Eastern Kingsnake
Lampropeltis getulus
Generally secretive and terrestrial through likes borders of swamps.
Swims readily. Largely nocturnal in hot weather. Eats snakes,
turtle eggs, rodents, and small birds.
Eastern Milk Snake
Lampropeltis triangulum
Secretive. Feeds on rodents, birds, lizards, and snakes.
Northern Copperhead
Agkistrodon contortrix mokeson
Uncommon. The only venomous snake on the Refuge. Often found
near rotting logs or piles of debris. Mice, frogs, and lizards are the
principal food.
| Copperhead |
 |
| Copperheads are the only
poisonous snake found on
the Eastern Shore of
Maryland. These golden-brown
patterned snakes are shy
and not commonly seen.
They are not aggressive and
(as is true with most animals)
will not bite unless provoked
or startled. |
Amphibians have no external scales, two pairs of limbs for
walking or
swimming, and usually a moist skin; they include salamanders, toads,
and
frogs. Amphibians derive their name (amphibious double life) from
their adaptation to a life both in the water and on land.
Salamanders
Marbled Salamander
Ambystoma opacum
Largely subterranean, living underground except during brief breeding
season in autumn. Eats earthworms and other invertebrates.
Spotted Salamander
Ambystoma tigrinum
Subterranean. A very early spring breeder.
Red-spotted Newt
Notophthalmus viridescens
Largely aquatic, except in land stage, the red eft form. May
remain active all winter in aquatic form, even under ice.
Red-backed Salamander
Plethodon cinereus
Terrestrial. Nocturnal, hiding under all manner of objects by day.
Feeds primarily on insects and spiders.
Eastern Mud Salamander
Pseudotriton montanus
Found in muddy places. Burrows in mud to escape.
Toads and Frogs
Eastern Spadefoot Toad
Scaphiopus holbrooki
Usually found in areas with sandy soil.
American Toad
Bufo americanus
Possibly occurs on refuge. Primarily nocturnal, feeds on insects.
Fowler's Toad
Bufo woodhousei fowleri
Abundant throughout the Refuge, in freshwater and brackish marsh areas,
fields and woods. Feeds largely on insects. Primarily nocturnal.
| Fowler's Toad |
 |
| Fowler's Toad, named for
an early Massachusetts
naturalist S.P. Fowler,
blends in perfectly with
its environment. At
Blackwater in the spring and
summer months, sunset is
accompanied by the
beginning of the nightly
toad and frog chorus that
will echo on until dawn. |
Northern Cricket Frog
Acris crepitans
A small nonclimbing frog of permanent bodies of water with emergent
vegetation for cover.
Northern Spring Peeper
Hyla crucifer
A small woodland frog. Arboreal. Prefers swamps or wet woods.
Seldom noticed except in spring breeding season when their piping song
is heard.
Green Treefrog
Hyla cinerea
Arboreal. Throughout fresher wetlands.
Gray Treefrog
Hyla versicolor
A small tree frog, seldom seen on the ground; usually forages
in small trees and shrubs. Can be found in dry as well as freshwater
habitats.
Chorus Frog
Pseudacris triseriata
A small treefrog that climbs very little. Can be found in dry
as well as freshwater habitats.
Eastern Narrow-mouthed Frog
Gastrophryne carolinensis
Nocturnal, burrows in damp areas. Ants are primary prey.
Bullfrog
Rana catesbeiana
A large and common frog in the larger bodies of fresh water.
Feeds primarily on insects, as do nearly all frogs.
Green Frog
Rana clamitans melanota
May be found wherever there is shallow fresh water.
Southern Leopard Frog
Rana utricularia
Common in shallow freshwater habitats. Also at edge of
brackish marsh. Ventures well away from water in summer.
Pickerel Frog
Rana palustris
Common in freshwater and brackish marsh. Also found in fields
and wood margins.
All turtles and snakes in this list have been identified on
Blackwater
Refuge by Refuge staff. The occurrence of some of the more rare and
secretive
reptiles and amphibians has not been fully substantiated; however, they
are included here due to their expected occurrence based on range and
habitat
data. To aid in further refinement of thislist your observations
and suggestions are welcomed.
