eWestern BirdsThe Quarterly Journal of Western Field Ornithologists
Vol. 31, No. 3
Western Field Ornithologists
Nesting of Ashy Storm-Petrels and Cassin's Auklets in Monterey County, California
Gerard J. Mcchesney, Harry R. Carter, Michael W. Parker
ABSTRACT: We report the first known nesting of the Ashy Storm-Petrel and Cassin’s Auklet in Monterey County, California, on offshore rocks around Castle Rock and Hurricane Point. Four nests and 13 mist-netted storm-petrels, together with the extent of suitable habitat, suggest a population of 10 to 30 pairs. A single abandoned Cassin’s Auklet egg, pink guano, and small numbers of other potential nest sites imply no more than five pairs of that species. Similar small colonies of these species may be scattered on similar offshore rocks along the central California coast, linking the major colonies on the Farallon and Channel islands.