PROTECTION STATUS: Threatened
YEAR PLACED ON LIST: 1987
CRITICAL HABITAT: 18,293 acres in San Mateo and Santa Clara counties designated in 2008
RECOVERY PLAN: 1998
RANGE: San Francisco peninsula, San Mateo County, Santa Clara County
THREATS: Urban development, pesticides, nitrogen deposition, overgrazing, global warming, and air pollution
POPULATION TREND: The Bay checkerspot has been eliminated from most of its serpentine habitat around the San Francisco Bay, and it is extinct in Contra Costa, Alameda, and San Francisco counties. By 1998, there were only five remaining core areas that supported Bay checkerspots and fewer than 12,000 acres of suitable habitat.