Vernal Pools

This vernal pool is one of several along the trail and in the forest. Vernal pools fill with water from rain and groundwater discharge, especially in the spring, and often shrink in size or dry up during the summer.

Vernal pool

Since vernal pools are formed in confined depressions with no permanent flowing outlets, they are free of fish populations. Fish eat amphibian eggs and juveniles. Several species of frogs and salamanders have evolved to use the fish-less vernal pools as safe places to lay their eggs in the spring.

To be classified a vernal pool, it must be used by at least one obligate or two facultative amphibian or reptile species.  An obligate species needs vernal pools for the successful completion of its life-cycle from an egg to grown adult.  A facultative species often uses vernal pools as a habitat for all or part of its life, but can also successfully reproduce in other water bodies that do have fish populations.

In New Jersey, there are seven amphibian species that depend on these pools for breeding. Two are endangered.  All fourteen frog species found in our state use these water bodies for breeding.  Vernal pools provide foraging areas for wading birds, turtles, snakes, and mammals that feed on the amphibians found there.  Rare plants can also be found in vernal pools, as well as insects such as dragonflies.

Obligate Vernal Pool Amphibians in Ocean County

Eastern Tiger Salamander (Ambystoma tigrinum)

Eastern Tiger Salamander (Ambystoma tigrinum) – Endangered
Marbled Salamander (A. opacum) – Special Concern
Wood Frog (Rana sylvatica)
Eastern spadefoot toad (Scaphiopus holbrookii)

Facultative Vernal Pool Amphibians in Ocean County

Green frog (Rana clamitans melanota)
Bull frog (R. catesbiana)
Pickerel frog (R. palustris)
Southern leopard frog (R. utricularia)

Northern Spring Peeper (Psuedacris crucifer)

Carpenter frog (R. virgatipes) – Special Concern
Northern cricket frog (Acris crepitans)
Northern spring peeper (Psuedacris crucifer)
New Jersey chorus frog (P. triseriata kalmia)
Northern gray tree frog (Hyla versicolor)
Southern gray tree frog (H.chrysocelis) – Endangered
Pine Barrens tree frog (H. andersonii) – Threatened
Four-toed salamander (Hemidactylium scatatum)
Fowlers Toad (Bufo fowlerii) – Special Concern

These reptile predators of amphibian eggs and young
can be found in vernal pools in Ocean County.

Spotted Turtle (Clemmys guttata)

Wood turtle (Glyptemys insculpta) – Threatened
Spotted turtle (Clemmys guttara) – Special Concern
Mud turtle (Kineosternon subrubrum)
Eastern painted turtle (Chrysemys picta picta)
Common snapping turtle (Chelydra serpentina serpentina)

Species Populations Status Categories

Endangered:  in immediate danger of becoming extinct
Threatened:  in significant decline
Special Concern:  shows evidence of decline in its population, or there is little understanding of its current population status in the state

Additional Resources

NJDEP Division of Fish & Wildlife: New Jersey’s vernal pools