Frogs are a familiar part of the wildlife of Massachusetts, and they’re found all across the state. Because of their diverse habitat needs and sensitive skin, these amphibians are good indicators of the health of our environment. There are 10 frog species in the Commonwealth, and one, the eastern spadefoot, is listed as Threatened under the state’s endangered species act.
Frogs tend to have bulging eyes and long back legs that help them hop, climb, or swim. They’re amphibians, so they rely on their environment to warm or cool them, and tend to lay their eggs in water.
All frogs belong to the order Anura, which means “no tail” in Latin. Toads are frogs; people have used the term toad for various unrelated species and groups of frogs. One group, the true toad family Bufonidae, has members that can be distinguished by large poison glands behind their eyes, shorter legs, and dry, typically warty skin.
Frogs can be surprisingly vocal. They make calls for a variety of reasons, including attracting mates, telling competitors to back off, and expressing alarm. The calls are valuable identification clues.
Many creatures eat frogs, including herons, northern water snakes, minks, raccoons, and more. Frogs use several strategies to avoid predators. They may leap away, produce distasteful or even poisonous chemicals, hide underground, and/or or use camouflage colors.
Frogs generally breed in wetlands. Their mating behavior, called amplexus, involves the male grasping the female and fertilizing her eggs as she releases them. The jelly-like eggs are deposited singly or in masses on underwater plant material or in free-floating films.
When the young hatch, they are tadpoles, breathing through gills and swimming with the help of a flattened tail. Over time they develop legs, lose their tail, and breathe air.
Most tadpoles eat aquatic plants and detritus, but some consume animal prey such as small fish. Adult frogs are important predators of insects. Large frogs may eat other small animals such as mammals, amphibians, and fish.