Amphibians Amphibians are coldblooded vertebrates that lay eggs in water and spend the first phase of life underwater. American Toad American toads are found throughout the northeastern US and the most common toad in New Hampshire. Pickerel Frog Pickerel frogs are one of the most beautiful animals around. They frequent ponds and lakes but sometimes stray further afield. Spring Peeper Spring peepers are small tree frogs, easily identifiable by the X on their back.