CREDIT: MARK BUTTO
Vernal pools are seasonal wetlands that serve as a vital habitat for many native species including frogs, salamanders, fairy shrimp, dragonflies, and more.
These pools go by a variety of names: prairie potholes, whale wallows, hog wallows, sinks, and kettles. They often can be found in small basins at the base of trees or in natural depressions in the landscape and can even be smaller in diameter than an average office desk and only a foot or so deep. Unlike many other wetlands or waterways, they are not connected to any other water source.
When trees are without leaves in winter and early spring, the groundwater remains uncollected by the tree roots and stays at the surface and collects in pools. Dead leaves attract insects, which can be food for salamanders and other amphibians, and offer hiding places from predators. These seasonal bodies of water (vernal is derived from the Latin word for spring) may be fleeting, but they play a critical role in the ecology of many forests and prairies by sheltering and providing breeding habitat for many species.
Because the pools do not retain water year-round, they are fishless! This makes them a safer space for many animals to lay their eggs with a lower threat of them being eaten. Many native frogs, salamanders, dragonflies, and even fairy shrimp depend on vernal pools as a breeding spot.
Many vernal pools are on private lands, and many have been lost to development and drought. Vernal pools are a great addition to gardens and adding one to your garden or taking steps to protecting existing pools counts toward the water requirement to become a Certified Wildlife Habitat®.
Tips for Maintaining Vernal Pools:
- Do not fill areas of natural depression and let the areas dry up naturally. Since these pools will become dry by summer, mosquitoes do not have warm enough water to lay eggs in.
- Leave trees, brush, dead logs in place, which can attract many types of wildlife.
- Do not dump or dig into a pool, which can affect the area’s ability to hold water.
- Leave space around a vernal pool, a minimum of a 100-foot natural buffer, to maintain the habitat and food supply for its residents.
