Vernal pools may be found in depressions in wooded areas, river floodplains or in the case of this picture, along the upper beaches in southwest Washington. These pools are typically small and shallow, and provide breeding habitat for frogs, such as the Great Basin spadefoot toad, salamanders and fairy shrimp on the east coast.

Vernal pools are also known as temporary or ephemeral ponds. They are usually about 25' x 75' and usually under 4' deep. Vernal pools exist where there are

1. no other sources of permanent water,
2. must not get too much water because it will become a permanent pond, but can't drain too much either, and
3. there must be poor drainage to hold the water until the warm weather causes the water to evaporate.

If you look closely, the color of the grass changes. The darker grass is where the vernal pool is located. The white object on the left side of the picture is a GPS (Global Positioning System) unit. It was retrieving the exact location of the pool from satellites.