A pond is a body of water smaller than a lake. Ponds support a wide range of wildlife: ducks, turtles, swans, small fish, and frogs can live in a pond. Usually, in most ponds sunlight can reach to bottom. In some cases, ponds do not last all year round. This type of pond is called a vernal pond, or ephemeral, seasonal, or temporary wetlands. These types of ponds do not have any fish. Some ponds are now getting polluted because of humans. Unlike rivers, lakes stay in one place. They do not flow from one place to another.