Amphibians are small vertebrates that need water, or a moist environment to survive. Amphibians consist of frogs, toads, salamanders, newts, and caecilians. Because they are cold blooded, with a very thin skin, they need specific living conditions. They can actually breathe and absorb water through their skin. However, with too much sun or wind can damage and dehydrate them. Unfortunately, amphibians are the most threatened class because they are susceptible to environmental threats such as pollution and climate change.
Amphibians and reptiles can be monitored as indicators of environmental changes, most particularly in the water. An assortment of contaminants, fungi, parasites, and diseases are impacting their breeding and development. From 1999 to 2009 the park collected data on frogs by listening to their calls.
Visitors can expect to hear the steady peep and confrontational trill of spring peepers beginning in February through early March, and again in the fall. If it is quiet visitors may hear the snoring sound made by the pickerel frog or the soft quacking noise of the southern leopard frog. There is a lull in breeding in April then the glunk of green frogs and moan of bull frogs continues until August.
An American Bullfrog on a lily pad
Jenny Glenn
American Bullfrog
The bullfrog’s coloration ranges from green to olive or brown with a white to yellowish belly and dark-barred legs. They breed in early summer; the eggs are laid in water and hatch into dark-spotted greenish brown tadpoles. Depending on climate, the tadpole stage lasts one to three years. Bullfrogs are voracious, opportunistic, ambush predators that prey on any small animal they can overpower and stuff down their throats. Bullfrog stomachs have been found to contain rodents, small lizards, other frogs, amphibians, crayfish, small birds, scorpions, tarantulas and bats, as well as the many types of invertebrates.
A green frog on the edge of the display pond
Tim Ervin
Green Frog
Despite its name, the Green Frog can be green, brown, or even blue. They’re commonly found in the Eastern United States in freshwater environments. These frogs are ambush predators, sitting quiet and still until an unfortunate macroinvertebrate crosses its path. In the winter, they dig themselves a burrow and hibernate until the weather warms again. Come Spring, these frogs can lay 7000 eggs in a single clutch.
A fowlers toad on the path
Jenny Glenn
Fowlers Toad
These little toads can range from brown to gray to olive, with raised bumps on their skin and a pale underbelly. They can be found in a range of habitats include floodplains and marshland. As tadpoles, these toads help aquatic plants like Lilys and Lotus’s by eating bacteria off their roots and stems. As adults, they mostly hunt for snails and insects during the nighttime.
A Pickerel Frog in the grass
Jenny Glenn
Pickerel Frog
Pickerel Frogs have a characteristic pattern of brown rectangles in two columns along their backs. Right next to those columns are two continuous ridges. In the winter, these frogs bury themselves in the mud at the bottom of our ponds, and in the summer, they love to be in ponds with lots of vegetation. They forage for insects in grassy areas next to the water. Their predators include snakes and other, larger frogs.
An American Toad in moss
Jenny Glenn
Eastern American Toad
These toads are common in the Eastern United States. They will thrive in any habitat with enough humidity to keep their skin moist and insects to keep them well-fed. They hibernate during the winter by burying themselves in either soil or leaf litter. Eastern American Toads hide under areas like boardwalks during the daytime, and they come out at night for the buggy meals.
Northern Leopard Frog
Gary Eslinger / USFWS photo
The Northern Leopard Frog
The northern leopard frog is a smooth-skinned, green, brown, or sometimes yellow-green frog covered with large, oval dark spots, each of which is surrounded by a lighter halo or border. It has a white to cream-colored underside and distinct, unbroken paler dorsolateral ridges, or fins, along both sides of the back. Northern leopard frogs breed in a variety of aquatic habitats, such as the marshy edges and side channels of streams or rivers. However, they also breed in springs, wetlands and beaver ponds. They lay their eggs in still, permanent water in areas exposed to sunlight, usually attaching the eggs to vegetation just below the surface of the water. Adult and juvenile northern leopard frogs eat small invertebrates, spiders, mollusks, and crustaceans. Tadpoles are generalist herbivores, eating algae, plant tissue, organic debris, and probably small invertebrates.
Wood Frog on moss
NPS Photo
Wood Frog
A wood frog’s most distinct characteristic is the black marking across its eyes, which has been said to resemble a mask. The bodies of wood frogs can be varying shades of brown, red, green, or gray, with females tending to be more brightly colored than males. These frogs have adapted to cold climates by freezing over the winter. During this time, they stop breathing and their hearts stop beating. Their bodies produce a special antifreeze substance that prevents ice from freezing within their cells, which would be deadly. Ice does form, however, in the spaces between the cells. When the weather warms, the frogs thaw and begin feeding and mating again.
