Reptiles and amphibians are known together as "herps."  These cold blooded animals use habitats and environments to regulate their body temperature. This may include hibernating in the winter, basking on sunny logs in the spring or seeking a shady area in the summer.

Amphibians have a 2-stage life cycle, most commonly seen in the change of a tadpole into a frog. While amphibians have delicate skin, reptiles have scales and plates.  The jelly-like amphibian eggs require moisture to prevent drying out. Reptile eggs are instead covered by a thick leathery shell which prevents water loss. All turtle and frog species lay eggs, some snake species, including the 3 found at Tinicum, bear live young.

There are 8 turtle, 3 snake, 2 toad, and 6 frog species known to inhabit the Refuge.

Toads and Frogs

Frogs and toads can be heard and identified by their calls during the spring and early summer.

John White Photo Bull Frog (Rana catesbeiana)	Abundant. The largest frog at the Refuge (3.5-6 inches) is a resident of lakes, ponds and sluggish streams.  Its back is yellowish-green to brown, sometimes mottled with dark brown.  Their familiar "Jug-O-Rum" call is most often heard through late May and June.
Credit: USFWS Green Frog (Rana clamitans melanota)	Abundant. This medium-sized frog is often mistaken for its larger cousin, the Bull Frog.  Its color is highly variable, from green, bronze, to brown.  The breeding call of the male can be likened to someone plucking a loose banjo string.
John White Photo Wood Frog (Rana sylvatica)	Abundant. This species is the first one to emerge from hibernation, often in late February or early March, gathering at small ponds for breeding.  A small frog (1 and 3/8 - 2.75 inches) wearing a "robber's mask", a dark patch extending backward from the eye, is quite visible in any color variation.  The mating call of the male sounds like a duck quacking.
Credit: USFWS Leopard Frog (Rana utricularia)	Common.  An endangered species in Pennsylvania.  A small frog (2-3 inches) with round brown spots.  The call of the male is a low gutteral trill.
John White Photo Pickerel Frog (Rana palustris)	Abundant.  Similar in size to the Leopard Frog.  It has smooth skin with square or rectangular brown splotches.  An early breeder, usually in March and early April.  The breeding call is a long, low-pitched snore.
John White Photo Spring Peeper (Pseudacris crucifer)	Abundant.  On the first warm evening of late March and early April, this very small frog (1.25 inches max) gathers at ponds for breeding.  The loud whistle of the males is completely out of proportion for their size.  A small chorus frog: tan, gray, or dark brown in color, with a large dark X on its back and a dark bar between the eyes.
John White Photo American Toad (Bufo americanus)	Rare.  While common throughout the rest of the state, it is quite rare within the Refuge.  Size is 2-4 and 3/8 inches.  Has warty skin, usually brown but highly variable, each dark spot has 1-2 warts, the throat is speckled, and it has enlarged warts on the tibia.  The call is a musical trill that can last up to 30 seconds.
Credit: USFWS Fowler's Toad (Bufo woodhousei fowleri)	Rare, though more common than the American Toad in the Refuge.  Size is 2-3 inches,  Has 3 or more warts in each of the largest dark spots, a virtually unspotted chest and belly, and no greatly enlarged warts on the tibia.  The call has been compared to the bleat of a sheep..

Turtles

Abundant but seldom seen during June when females leave the water to lay eggs. It is the largest turtle at the Refuge, reaching a weight of 50-60 lb. with a shell length of 8-12 inches (record size is 18.5 inches).  Colored brown or greenish with massive head, powerful hooked jaws, and long tail with sawtoothed keels.

Common but secretive and seldom seen.  Small in size with an average shell length of about 3.5 inches.  Color varies from light olive brown to almost black, with 2 light stripes on head and sensory barbels on chin and throat.  Its name comes form the foul-smelling odor it exudes when threatened.

An endangered species in Pennsylvania, similar in size (3-4 inches) and appearance to the Stinkpot.  Its head is striped, mottled, or irregularly streaked with yellow.  None have been seen at the Refuge in recent years.

Fairly common, this land turtle is often encountered at the Refuge.  Its high domelike shell averages 4-8.5 inches in length, and is variable in color and pattern.  Males can be distinguished from females by their red eyes.

Rare.  A turtle of brackish bays and estuaries which occasionally comes up Darby Creek on high tide.  Shell length is 4-9 inches.  Gray head and neck peppered with black.  Unusual sculptured shell;  plates bear deep growth rings.

Abundant.  The most frequently observed reptile at the Refuge, usually seen basking in the sun on logs or stumps. Its 4.5-6 inch shell is low, oval smooth and unkeeled with an olive-green to black color. Marginal plates are accented by red bars or crescents.  Head and legs have yellow and red stripes. Though some Painted Turtles in Pennsylvania exhibit field markings of the Eastern or of the Midland species, most have combination markings from both.

Fairly common.  A popular pet store turtle originally from the Mississippi River Basin.  Because of releases, it is now established throughout the United States.  It is usually seen sunning with Painted Turtles, and is the only North American turtle with a conspicuous red stripe on the side of its head. Shell length is 5-8 inches.

Common.  A threatened species in Pennsylvania.  Usually seen sunning with Painted Turtles, but is almost twice the size of that species with a shell length of 10-12.5 inches.  Color varies from brown to black with a mottled pattern of reddish brown.  Several vertical red bars run from the center of the shell to its outer edge.

Snakes

Common.  Often seen sunning on muskrat houses. A large (24-42 inch) heavy-bodied snake often mistaken for the poisonous Water Moccasin.  The water moccasin is not found north of the Dismal Swamp in Southern Virginia.

Abundant.  The most frequently seen snake at the Refuge, particularly in May and June.  Size ranges from 18-36 inches.  While color and pattern are highly variable, the one back and 2 yellow side stripes are usually well defined.

Abundant.  A small secretive brown snake seldom reaching a length of more than 12-13 inches, and with 2 parallel rows of blackish spots down the back.  A few of the spots may be linked with their partners across the body by narrow lines of pigment