Vernal ponds (also called ephemeral, temporary, or seasonal ponds, pools, or wetlands) are areas that do not contain water year-round. Instead, these areas fill with water seasonally, usually with the onset of spring (vernal) or fall rains, and then dry up in the late summer. Vernal ponds are one of the most critical amphibian habitats.
Many predators of amphibians live in permanent bodies of water, including fish, invertabrate predators, and even other amphibians, such as American Bullfrogs and Northern Green Frogs. Many of Ohio's amphibian species rely on the relative safety that temporary pools offer for egg-laying and the development of their larvae.
Habitat destruction is the major threat to vernal ponds. Often, people mistake seasonally wet areas as "wasteland," and proceed to fill in or drain these critical habitats. Sometimes landowners mistakenly believe that by making a vernal pond permanent (by digging it bigger and deeper) they are increasing the value of the area for wildlife.
What can you do to protect vernal ponds? Do not alter the vernal pond to make it deeper. Do not introduce fish or other predators of amphibians to the pond. Keep a buffer around the pond. Buffers are areas of natural vegetation (not turf grass) that help filter the water flowing into the pond and provide areas for the terrestrial amphibians to live.
For more information about vernal ponds:
Habitat Management Guidelines for Ephemeral Wetlands
Vernal Pools: Natural History and Conservation. By: Elizabeth A. Colburn.