Why is This Important?

San Mateo County is home to a diverse mix of natural habitats, including beach and intertidal zones, coastal sage scrub, chaparral, oak woodlands-even redwood forests. Each of these ecosystems supports its own variety of plants and animals, some of which are endangered or threatened. The availability of and access to these habitats provides a number of benefits to county residents, including tourism, recreation, and increased property values.

What is a Sustainable State?

In a sustainable state ecosystems are healthy and land use decisions include habitat protection.

How Are We Doing?

Threatened and endangered species
San Mateo County is home to 25 endangered species and another 15 threatened species. A number of these species have "critical habitat" located within the county.
• The coho salmon (endangered) and Central California Coastal steelhead (threatened) spawn in small streams in the county before migrating to the ocean for most of their adult lives. Pollution, decreased water quality, dams, and poor stream conditions have greatly diminished the prevalence of both fish in the county.
• The California red-legged frog has been lost from 70 percent of its historical area, mainly from loss of habitat to coastal development.

Invasive species
The San Mateo County Department of Agriculture and nonprofits like the California Native Plant Society maintain active programs to intercept and eradicate invasive and exotic species in the county. The Pest Exclusion program is the first line of defense in keeping exotic plants, insects, and plant diseases from impacting the county's agriculture industry and native environment. Exotic pest interceptions in San Mateo County totaled 1,128 in 2008, more than twice the number in 2005.

Bird populations
The Audubon Society's Christmas bird count tracks bird populations at two locations in San Mateo County: Año Nuevo and Crystal Springs. Three species are indicators of the overall ecosystem health: the common raven because its population is closely tied to human presence; the acorn woodpecker because it is a cavity nester that depends on oak habitats for survival; the California quail because it is vulnerable to human disturbance.

Although there can be great variation in the annual counts due to weather and other factors, since 1986 the number of common raven has grown steadily while the number of acorn woodpecker and California quail counted has decreased slightly.