1921 BIRDS OF MONTANA 61 



state. Records in the eastern pai-t of the state are few. Tho'c arr no records of 

 this species by the earlier observers, which leads to tiie belief tiiat tiic species has 

 become common in recent years. Winters occasionally on the west side of the 

 divide. Records in the eastern half of the state : Custer and Dawson counties, 

 summer resident, probably breeds (Cameron, 1907, p. 260) ; Fergus County, nest 

 and four eggs, June 6, 1900 (Silloway, 190::ia, pp. 27-28, and 1901c, pp. 7(i-71) ; 

 nest at Flathead Lake. July '■'>. 1900, four eggs advanced in incubation (Sillo- 

 way, 1901a, p. 31). Young are nearly full grown and ready to leave the nest 

 by about August 25 in Powell and Deer Lodge counties. This bird nests most 

 eommonly in the mountains in low thick growths of sju-uce. In the prairie 

 region they probably nest in cottonwood groves. I)ut the nest has yet to be found 

 there. 



Migration dates: Spring. May 1.3, 1909, Big Creek, Park County; April 

 12, 1910, Divide Creek, Silver Bow County; April 2:i, 1911. Anaconda; May 8, 

 1912, Choteau. Fall. Octolicr (i, 1908, Gallatin County; Septeiul)i'r 26, 191(1, 

 Race Track; September 18, 1911, and September Ki, 1912, Choteau. 



Winter records: Silver liow, January 2, 1911 (Saunders, 1912a, p. 2.5) ; 

 Bitterroot Valle.v, usually rai-c'in winter, but conuiion at that season when Red- 

 polls are abundant (Bailey, MS). 



109. Accipiter cooperi (Bonaparte) 



Cooper II.wvk 



Summer resident throughout thr state liut commoner in tlie western half in 

 the mountains. Less common than A. r< lor. There are no nesting records from 

 extreme eastern Montana, where it may bi- only a migrant, though there are sev- 

 eral records in late .summer. There are no definite nesting records from any 

 section ; so far as records show the nest has never been found in the state. In 

 most places the hawk is regarded as rare, but Bendire calls it the commonest 

 hawk in southwestern Montana (1892, p. 194). 



Migration dates: Dawson County, Ajiril :!0, 1903 (Cameron, 1907, p. 260) ; 

 Silver Bow County, April 30, 1910; Anaconda. April 20, 1911; Choteau, April 

 22, 1912. Fall: Custer County, September 13, 189.3 (('amcron, 1. c). 



110. Astur atricapillus atricapillus (Wilson) 



Eastern ( j o.s h .\ w k 



A fall migrant through the eastern hall' of the state, extending its I'angi' 

 west into the mountains east of the continental divide, and perhaps farther wi'st- 

 ward. This form may be a summi'r i-esident in sniiie parts of the state, but the 

 only definite identification of a breeding hii'd pi'dved to i)i' that of the western 

 sidjspecies. Records; ('uster and Dawson counties, September 22. 1903, Octolier 

 18, 1905, November 19, 1905, September-October, 1906, October 18-27, 1906 

 (Cameron, 1907. [ip. 261-262). Gallatin County, three seen and oiu^ taken 

 (Richmond and Knowlton, 1895, p. 302). Gallatin River, October 30, 1908 

 iSaunders, 1911a, p. 36). Park County, October 21-25, 1908. 



Winter record: Gallatin County, December 21, 1908 (Saunders. 1909a, 

 p. 35). 



