Figures 59–61 (top to bottom). Despite the Wedge-tailed Shearwater’s abundance in the tropical Pacific Ocean, including waters off mainland Mexico, the CBRC has endorsed only four occurrences in California. Three are fall records from Monterey Bay, including the two birds pictured here. The top and middle images show a dark-morph individual photographed on 10 October 1998, the day of its discovery (1998-162; Bill Boyce top, Don Cunningham middle). At the bottom is a first-year, light-morph bird photographed on 26 September 1999 (1999-189; John Sorensen).

 

 

 

WEDGE-TAILED SHEARWATER Puffinus pacificus (Gmelin, 1789)

Accepted: 4 (29%)	Treated in Appendix H: no
Not accepted: 10	CBRC review: all records
Not submitted/reviewed: 0	Color image: none

This shearwater is widespread in warm, tropical waters of the Pacific and Indian Oceans. Nesting takes place on numerous islands, including the Hawaiian Islands and San Benedicto of the Islas Revillagigedo. The species is regular in waters off the Pacific coast of mainland Mexico south of the Gulf of California. Dark-morph birds have strayed twice to Oregon (one found dead on 26 March 1999 at Newport and one observed on 2 October 1999 about 25 nautical miles off Depoe Bay) and Washington (one found dead on 10 September 1999 at Ocean Beach).

California’s first Wedge-tailed Shearwater was a light-morph bird found on 31 August 1986 at Monterey Bay, Monterey County (Stallcup et al. 1988). Given this species’ abundance and range, the state’s total of four acceptable records (31 July–21 October) seems low. In light of the CBRC’s skepticism about many reports of this species, observers are encouraged to take particular care in documenting their sightings. Most reports that the CBRC decided against were supported by descriptions that showed a lack of appreciation for subtle identification criteria such as leg color and wing shape (see Stallcup et al. 1988, Stallcup 1990).

The Wedge-tailed Shearwater is polymorphic, with light birds, dark birds, and intergrades. The light morph predominates in Hawaii (King 1974), but dark birds have long outnumbered light ones on San Benedicto (Anthony 1898), and more recently Jehl and Parkes (1982) found almost no light-morph birds in this population. This species is abundant, widespread, and variable, and extralimital records may not have originated from the nearest colonies, so any inferences about the potential provenance of a California record based on the morph involved would be speculative.