The California brown pelican has recently been delisted, and is an amazing conservation success story. These birds have been observed roosting at Seal Rocks, Alcatraz Island, Hyde Street Pier, Bird Island, and Kent Island in Bolinas Lagoon. Brown pelicans feed on small fish such as the anchovy along the Pacific coast and in Bolinas and Rodeo lagoons. Threats to this species include boating and active recreation in roosting areas, oil spills, and climatic factors affecting anchovy availability.
The threatened marbled murrelet are found in forest stands with old growth characteristics, and are extremely sensitive to disturbance and noise in the vicinity of nesting areas. A few unverified inland sightings have been reported since 1990. Systematic surveys have been conducted in Muir Woods National Monument and no murrelets have been detected. Marbled murrelets are infrequently seen in nearshore waters from mid-summer through winter. Detection of breeding murrelets in Marin would be extremely significant as there is a geographical gap between breeding populations in San Mateo and Santa Cruz counties to the south, and Mendocino County to the north. Threats to this species include range expansion of ravens, urban development, and urban recreational pressures.
The threatened bank swallow colony at Fort Funston is the largest nesting colony of bank swallows in the San Francisco Bay Area. Bank swallows migrate from South America to nest in the hundreds of burrows that cover the sandstone cliffs. Watching these aerialists capture insects on the wing and then feed their young while hovering in front of the burrows is a sight to see. Threats to this species include burrow invasions from European starlings, predation by American kestrels, and conflict with recreational uses such as hang gliding and rock climbing. The sandstone bluff is extremely erodible, and intense storm events are also a threat.