The Goshawks 



No. 329 



Goshawk 



No. 329a American Goshawk 



A. 0. U. No. 334. Astur gentilis atricapillus (Wilson). 



Description. — Adult: Similar to A. g. striatuhis, but less heavily marked 

 below and the markings paler, — never blended blue-gray; upperparts not so dark, 

 slate-gray. Immature: Brownish black of back and striping of underparts lighter in 

 tone than in striatuhis. 



Nesting. — As in next form. Does not breed in California. 



Range of Astur gentilis. — Central northern portion of the Northern Hemis- 

 phere, south in winter to North Africa, Thibet, and Mexico. 



Range of A. g. atricapillus. — North America, except the Pacific Coast district- 

 Breeds from the limit of trees south to Michigan and northern New England and in 

 the mountains to Pennsylvania and New Mexico. Winters from Alaska and the 

 southern Canadian provinces south to northern Mexico, the northern portion of the 

 Ohio Valley, and Virginia. 



Occurrence in California. — Probably not common winter visitant. A notable 

 invasion from the North in the fall and winter of 1916. Many records. 



Authorities. — Grinnell, Condor, vol. xix., 1917, p. 70 (winter vis.; specimens 

 from various localities; crit.; color of "soft parts"; meas. ; etc.); Thompson, Auk, vol. 

 xiv., 1897, p. 395, pi. ("directive" markings in hawks and owls). 



No. 329b Western Goshawk 



A. O. U. No. 334a. Astur gentilis striatulus Ridgway. 



Synonyms. — Goose Hawk. Blue Hen Hawk. Blue Darter. 



Description. — Adult: Above dark plumbeous to sooty blackish; with darker 

 shaft-lines; darker, almost black on head; white lines over and behind eye loosely 

 connected by ill-concealed basal white of cervical feathers; auriculars blackish; tail 

 with four dusky bands, plain, or almost obsolete; inner webs of wing-quills mottled, — 

 dusky and whitish; entire underparts white, finely and heavily marbled with slaty 

 gray, in fine wavy or zigzag lines, sometimes so closely as to appear almost uniform 

 blue-gray, the markings falling into fine bars on flanks and tibiae, with sharply defined 

 blackish shaft-lines on throat and breast. Bill dark blue; iris light yellow; feet yellow, 

 claws black. Immature: Following the Accipiter fashion; above dark brown, spotted 

 with buff and whitish and margined with rusty; tail with narrow white tip and four 

 distinct dusky bands; below whitish to strong ochraceous-buffy, elongate-spotted or 

 striped with dark brown or blackish, the markings guttate on belly, broader, on sides 

 and flanks. Adult male, length about 558.8 (22.00); wing 304.8-342.9 (12.00-13.50); 

 tail 241.3-266.7 (9.50-10.50); bill from nostril 19. 1 (.75). Adult female, length about 

 609.6 (24.00); wing 336.6-362 (13.25-14.25); tail 279.4-317.5 (1 1. 00-12. 50). 



Recognition Marks. — Crow to brant size; adult dark plumbeous above, white, 

 finely mottled with slaty gray below; rather short, rounded wings; white line over 

 eye; tail a foot long. 



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