The Heermann Gull 



No. 281 



Heermann's Gull 



A. O. U. Xo. 57. Blasipus heermanni (Cassin). 



Synonym. — White-headed Gull. 



Description. — Adult in breeding plumage: Mantle plumbeous-slate; head and 

 neck shading into deep ashy gray of remaining plumage; upper tail-coverts light ashy; 

 greater wing-coverts and tertials tipped with ashy and whitish; wing-quills and tail 

 black, the latter broadly, the former (except 1st and 2nd primaries) narrowly, tipped 

 with white. Bill rich vermilion, tipped narrowly with black; feet and legs reddish 

 black. Adult in winter: Head and neck lightly streaked with dusky. Young of 

 the year: Entire plumage sooty brown, lightening on throat, blackening on quills 

 and tail; a little whitish skirting below, more on wing-coverts; also, or not, tail faintly 

 white-tipped. Bill (drying) yellowish at base. Immature: Mingled sooty and plum- 

 beous; head darker and more uniform sooty blackish in contrast with cervix, but throat 

 white; no white on quills or tail. Bill dull orange basally, black at tip. Probably 

 attains maturity the third year. Length of adult: 444.5-533.4 (17.50-21.00); wing 

 342.9 (13-50); bill 44-5 (1-75); depth at angle 14 (.55); tarsus 55.9 (2.20). 



Recognition Marks. — Crow size; black and vermilion beak; dark body plumage 

 unmistakable in any feather; mellow notes. 



Nesting. — Does not breed in California. Nest: A mere depression in loose 

 soil, unlined. Eggs: 2 or 3; of somewhat lighter coloration than "normal gull type," 

 and more finely spotted. Av. of 28 eggs in M. C. O. coll.: 59.3 x 41.9 (2.335 x I &5)\ 

 index 71. Season: c. April 8. 



General Range. — Coasts of western North America. Breeds in March and 

 April on the Tres Marias Islands near Tepic, and upon islands in the Gulf of California, 

 north at least to Ildefonso. At other seasons ranges north along the seacoast to Van- 

 couver Island and the Gulf of Georgia. 



Distribution in California. — More or less common along the coasts and 

 harbors throughout the year, but numbers greatly augmented in early winter by the 

 return of northern tourists, and depleted in early spring by withdrawal of breeding 

 birds. 



Authorities. — Cassin (Larus heermanni) , Proc. Acad. Nat. Sci. Phila., vol. vi., 

 1852, p. 187 (orig. desc. ; type locality, San Diego); Howell, Pac. Coast Avifauna, no. 

 12, 1917, p. 28 (s. Calif, ids.); Willett, Condor, vol. xx., 1918, p. 122, fig. (aberrant wing 

 markings). 



A-OWNH ownh ownh ownh ownh! A-ownh ownh ownh ownh ownh! 

 They are southern voices that are speaking, and the notes produce a 

 pleasing complex of impression, for they are sometimes drawling and 

 indolent, in spite of their accelerando cadence, and they are mellow and 

 limpid, for all of their nasal twang or their underlying suggestion of feline 

 moroseness. You have offended the dignity of an orderly meeting, and 

 these are protests. This ledgeful of dark birds, which you have just 

 disturbed by your thoughtless approach, is none other than the August 



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