Why Is This Important?
San Mateo County supports many plants and animals that are important to the health of local ecosystems and provide environmental and economic benefits to local communities. Development in sensitive areas, pollution, or the introduction of invasive species can all lead to habitat loss and destruction.
What Is a Sustainable State?
A sustainable state is one where ecosystems are healthy and land use or other decisions are balanced with the need for habitat protection.
How Are We Doing?
Threatened and endangered species
San Mateo County is home to over 40 state or federally listed threatened or endangered species. Species with important habitat in the county include:
- The San Francisco garter snake, found only in San Mateo County, feeds primarily on the federally threatened California red-legged frog. Both species prefer wetland habitats, which have been lost to agricultural, commercial, and urban development.
- The marbled murrelet uses coastal streams to move between the ocean and its breeding sites in the SFPUC watershed.
- The endangered mission blue and callippe silverspot butterflies are protected by a Habitat Conservation Plan (HCP) on San Bruno Mountain. This HCP was the first in the nation and has been protecting the butterflies since 1983.
- The Bay checkerspot butterfly and numerous plant species depend on the county’s serpentine soils, which have been severely degraded because of habitat loss and automobile emissions that fertilize invasive grass species.
The San Mateo County Weed Management Area is a regional organization formed by public agencies, private landowners, the agricultural industry, and environmental organizations that are concerned with invasive plant species in the county. Their top eight invasive species of concern are the yellow star thistle, jubata grass, pampas grass, French broom, Scotch broom, cape ivy, gorse, and fennel.
Bird populations have been tracked through the Audubon Society’s Christmas bird counts at Año Nuevo and Crystal Springs. Three species were chosen to show trends in bird populations.
- The common raven because its population is closely tied to human presence and disturbance.
- The acorn woodpecker because it is a cavity nester that depends on oak habitats for survival.
- The California quail because it is a ground-nesting species which is vulnerable to human disturbance.
Although there can be great variation in the annual counts, since 1986 the number of common raven has grown steadily. The number of acorn woodpecker and California quail counted has decreased slightly.
Data source: National Audubon Society
Habitat Restoration on Bair Island
Work on Bair Island in the Don Edwards San Francisco Bay National Wildlife Refuge will restore 1,400 acres of tidal marshland. Perimeter levees will be breached to allow tidal action via surrounding slough channels and excavations through internal levees will reestablish historic channels to facilitate circulation and drainage. The restored marsh complex will provide habitat for the endangered California clapper rail and salt marsh harvest mouse, and for other important San Francisco Bay wildlife such as the western snowy plover, California least tern, and California brown pelican. Begun in 2007, restoration work is hoped to be completed by 2010-11.
See appendix page 75, CLICK HERE. Researcher: Rachel Rounds