California's Valuable Wetlands

Much of the planet's life depends on the existence of wetlands. They are vital to the survival of many fish and other aquatic life forms, birds, and plants. They filter and clean water, prevent soil erosion, and provide flood control among numerous other benefits.

Some of the most important functions of wetlands are:

Water Quality Protection and Improvement

Water passing through a wetland carries with it organisms, sediments, nutrients, and pollutants. The vegetation and soil in the wetland form a kind of sieve, trapping those materials and filtering the water.

Flood Control and Groundwater Recharge

The retention and slow release of flows in freshwater wetlands can lessen the effects of flood peaks and provide groundwater recharge.

Erosion Control

Where a wetland borders a large or deep water body, vegetation protects against erosion by stabilizing banks and damping wave energy.

Fish and Wildlife

The combination of vegetation and open water in wetlands provides food, rearing areas, and cover for waterfowl and shorebirds, as well as spawning habitat and food for freshwater and marine fishes. Many species of birds and fish are absolutely dependent on wetlands.

Biological Diversity

Because aquatic and terrestrial habitats overlap in wetlands, they serve wildlife from both realms, as well as plants and animals that have adapted specifically to life within the wetlands The multitude of wetland organisms includes 41 of the state's rare and endangered species.

Recreation

The diversity of wildlife and aesthetic qualities found in many wetlands attract large numbers of outdoor enthusiasts, including hunters, anglers, boaters, birdwatchers, and photographers.

Even as appreciation for the benefits provided by wetlands has grown over the last couple of decades, wetlands continue to be filled, drained, and dredged. California today has only 10 percent of the wetlands that existed before settlement by Europeans. The Central Valley once had vast wetlands extending over some 4 million acres; these have diminished to a mere 300,000 acres. Only 5 percent of the state's coastal wetlands remain intact.

Government efforts in response to these losses have come in the form of legal restrictions on uses of wetlands as well as protection through acquisition, restoration, and management. While these approaches have done a great deal to preserve wetlands and prevent their indiscriminate destruction, they cannot reach all wetlands. The lands with the greatest potential for wetland restoration and management are mostly in private ownership. Landowners have the opportunity to play a significant stewardship role.

Webmaster: wetlands@resources.ca.gov