Why Do We Need Wetlands?

Wetlands are important for many reasons.  They provide important habitat for diverse communities of plants and animals, including over 50 percent of the federally listed threatened or endangered species.  Wetlands provide wintering habitat for migratory waterfowl; in the Bay Area, the wetlands along the Estuary are very important feeding and resting areas for birds migrating along the Pacific Flyway.  Wetlands also direct spawning and rearing habitats and food supply that supports both freshwater and marine fisheries. 

 Nearly 80 percent of the Bay's original wetland habitats have been diked and filled for farming, grazing, salt extraction, building and other development.  This loss of wetlands has greatly reduced the amount of habitat available to many species of fish and wildlife.  Several local animal and plant species, including the salt marsh harvest mouse and the California clapper rail, have been listed as endangered as a direct result of the reduction in extent and quality of their wetland habitats.  Many other species, including migratory shorebirds, waterfowl, and numerous fish species, also have been affected by this loss of habitats.

Wetland habitats play key roles in maintaining both a healthy ecosystem and economically vibrant region.  Besides providing fish and wildlife habitat, wetlands also improve water quality, protect lands from flooding, provide energy to the estuarine food web, help stabilize shorelines against erosion, and increase groundwater availability.  Wetlands also support extensive outdoor recreation.  Wetlands offer a broad range of non-biological benefits that include:


Wetlands can serve as natural remediation sites by enhancing water quality.  Many human and household wastes, toxic compounds, and chemicals such as fertilizers are tied to sediments that can be trapped in wetlands.  Plants and biological process in wetlands break down the convert these pollutants into less harmful substances.


Wetlands also contribute to the community through recreational activities such as fishing, hunting, and bird watching.  It is estimated that the annual economic value of wetlands statewide in California is between $6.3 and $22.9 billion.  The 1996 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation reported that 3.1 million adult Americans hunt migratory birds including geese, ducks, doves, and other game birds.  Nationwide, it is estimated that hunters spend about $1.3 billion on travel, equipment, and other associated expenses.



Wetlands can not only serve as biofilters, but they can also slow down and soak up water that runs off the land.  Wetlands are capable of lowering the volume of floodwaters and diminish flood heights which in turn reduce shoreline and stream bank erosion.  Preserving natural wetlands can reduce or eliminate the need for expensive flood control stuctures.


The vast majority of our nationís fishing and shellfishing industries harvest wetland-dependent species.  This catch is valued at $15 billion a year.  The economic benefits of wetlands also extend to other forms of commercial harvesting such as shell mining in the South Bay.  The South Bay formerly had one of the nation's most productive oyster beds with its harvest serving much of the West Coast.

References Used:

Baylands Ecosystem Habitat Goals, SF Bay Area Wetlands Ecosystem Goals Project
Feasibility Analysis: South Bay Salt Pond Restoration, Siegel and Bachand
Turning Salt into Environmental Gold, Save the Bay
Wetland Restoration, EPA fact sheet 843-F-01-002e
Wetland Overview, EPA fact sheet 843-F-01-002a
Types of Wetlands, EPA fact sheet 843-F-01-002b
Restoring the Estuary: An Implementation Strategy for the San Francisco Bay Joint Venture.  January 2001