Figure 154. In comparison to a California Gull (above), note especially the black tail band and darker mantle of this adult Black-tailed Gull (below). Collected on 28 November 1954 at San Diego Bay, San Diego County, it was the first of its kind to be found in North America. Despite a recent spate of records from across the continent, this occurrence remains unique in California (1977-143; Stephen F. Bailey).

 

 

 

 

 

BLACK-TAILED GULL Larus crassirostris Vieillot, 1818

Accepted: 1 (100%)	Treated in Appendix H: no
Not accepted: 0	CBRC review: all records
Not submitted/reviewed: 0	Color image: none

This gull occupies a relatively limited range that includes southernmost coastal Siberia, Japan, Korea, and eastern China. Post-breeding dispersal is primarily southward and not notably ambitious (Burger and Gochfeld 1996), although the species has reached Australia (Higgins and Davies 1996). In the New World, this gull has wandered numerous times to Alaska, including four times to southeastern Alaska (e.g., Heinl 1997, NAB 58:126), and has been recorded at scattered sites in Canada, the Northeast, and along the Atlantic coast south to North Carolina. The species has twice reached southern Texas (NAB 58:399, 456), and single birds visited Wisconsin/Illinois/Indiana (NAB 57:495, 574; 58:75–76) and Belize. Records closer to California involve an adult in southwestern British Columbia on 5 January 2002 (BJ 11:4), a subadult in southwestern Washington 3 August–30 October 2004 (NAB 59:138, 191), and an adult in northwestern Sonora on 7 June 1997 (Garrett and Molina 1998).

An adult female Black-tailed Gull collected on 28 November 1954, two days after being discovered at the north end of San Diego Bay in San Diego County (Figure 154), provided the continent’s first record by more than 25 years (Monroe 1955, Cogswell 1977). In the inaugural issue of California Birds, McCaskie et al. (1970) opined, “it is likely that this individual was induced to stay aboard [a navy ship] until it reached San Diego. The likelihood of this species ever reaching California as a genuine stray is very remote.” This viewpoint prevailed through two CBRC votes, but by 1992 enough was known about the Black-tailed Gull’s patterns of extralimital occurrence—including several records from Alaska and the Atlantic coast—to convince members that the San Diego record probably involved a legitimate vagrant (Heindel and Patten 1996). Although both the pace and the scope of New World records have only increased in recent years, a half-century has now passed without California notching a second record of this enigmatic species.

As noted in the previous account, observers identifying this species out of its normal range should be aware that Belcher’s and Black-tailed Gulls can look similar. Lethaby and Bangma (1998) provided information on Black-tailed Gull distribution and identification.