Vernal pools are unique wetlands best known for the amphibians and invertebrate animals that use them to breed. Vernal (Latin word for “spring”) pools are also known as seasonal pools, autumnal pools, temporary ponds, woodland pools, and ephemeral wetlands. They are isolated aquatic habitats that undergo periodic drying. Melting snow, run-off, and spring rains fill these small depressions in early spring, and then the pools dry out by middle or late summer each year or every few years. However, some pools fill at other times of the year, such as during autumn or winter from the rising ground water and rainfall. Fish cannot establish permanent populations due to its occasional drying.