Water—a requirement for most if not all life. Free flowing or standing water is indeed required by many species. Many amphibian species need free water during at least part of their life to lay eggs that will hatch and develop into adults before the water evaporates. Other amphibians spend all of their lives in water, such as aquatic forms of Pacific giant salamanders. Waterfowl use lakes, ponds, streams, marshes, and swamps as places to feed and raise young. River otters, snapping turtles, and bullfrogs are all aquatic predators that use resources in both aquatic and terrestrial environments. Because so many species are associated with free water, the interface between the water and the land, that area known as a riparian area, is usually given special consideration during forest management.
Riparian areas are perceived by many ecologists as being particularly important for animal species due to several conditions.