Bird Rock (Marin County, California)

Rock formations in the United States

The following is a partial list of rock formations in the United States, by state:-Arizona:*Canyon de Chelly National Monument**Spider Rock*Chiricahua National Monument**Duck on a Rock**Organ Pipe**Mushroom Rock**Sea Captain*Monument Valley...

and a small Pacific island west of Tomales Point in Marin County, California

Marin County, California

Marin County is a county located in the North San Francisco Bay Area of the U.S. state of California, across the Golden Gate Bridge from San Francisco. As of 2010, the population was 252,409. The county seat is San Rafael and the largest employer is the county government. Marin County is well...

at 38.2299191°N 122.9944445°W Its area is roughly 2 acre (0.809372 ha).

A seabird colony, the island is covered with a layer of guano

Guano

Guano is the excrement of seabirds, cave dwelling bats, and seals. Guano manure is an effective fertilizer due to its high levels of phosphorus and nitrogen and also its lack of odor. It was an important source of nitrates for gunpowder...

. Cormorants are common on the island, and Ashy Petrels

Ashy Storm-petrel

The Ashy Storm Petrel is a small, scarce seabird of the storm-petrel family Hydrobatidae. It breeds colonially on islands off the coasts of California and Mexico, and is one of six species of storm petrel that live and feed in the rich California Current system.-Taxonomy:The Ashy Storm Petrel was...

were found breeding there in 1972.

See also