BIRDS OF FERGUS COUNTY, MONTANA. , 15 



Distinguishing features: The male has upper parts bright reddish 

 brown, with sides of head white; lower parts whitish; length 13-16 inches. 

 Female grayish brown above, lower parts whitish. 



170. ROSS'S SNOW GOOSE. Chen rossii. 



Occurs regularly in migration. A small flock of six was seen on 

 Big Spring Creek a few miles below Lewistown on March 14, 1903. Capt. 

 Platte M. Thorne reports it as rare at Ft. Keogh. 



Distinguishing features: Entire head and part of neck white; other- 

 wise whitish, wings with black markings; length 20-26 inches. 



172. CANADA GOOSE. Branta canadensis. 



A regular migrant throughout the county, and breeding in suitable 

 localities. Dr. J. A. Allen reports that this species breeds along the Mus- 

 aelshell, and there is no doubt that broods are regularly reared along the 

 Missouri river border of the county. 



On the spring migration, the geese often appear by the first of 

 March, and sometimes they linger several weeks near a particular field, 

 feeding early in the morning and late in the day, and resorting to the 

 water at other times. 



Distinguishing features: Head black, with cheek-patches of white 

 meeting on the throat; upper parts brown, varied with gray; lower parts 

 lighter; length 34-44 inches. 



181. TRUMPETER SWAN. Olor buccinator. 



Occurs regularly throughout the county, occasionally breeding in 

 suitable places. A friend told me of seeing an old swan and a young one 

 upon the "Highland" lakes. The two were in flight between the lakes, and 

 the cygnet flew only a few feet directly above the elder, so that it could 

 drop on the parent's back at frequent intervals. The younger swan would 

 fly fifty or sixty yards alone, then drop lightly upon the parent's back to 

 rest, being carried for fifty to sixty yards in this manner; then it would 

 rise upon its own pinions, and flap along above the elder bird until it 

 again became weary of its own exertions. 



Distinguishing features: White, with black bill and cheeks; length 

 60-65 inches. 



190. AMERICAN BITTERN. Botaurus lentiginosus. 



The American bittern is found regularly throughout the county, 

 though nowhere in numbers. On May 19, I heard an individual of this 

 species in a bog along Big Spring Creek, near Lewistown, uttering its 

 hoarse "boo-hoo, hoo" notes all the afternoon, and later I flushed it sev- 

 eral times, when it would fly to another part of the bog farther along the 

 creek. The bittern is usually solitary, a hermit of the swamps, lurking 

 alone in the reedy tangle to glean its fare. One that I took in the summer 

 of 1901, in the Flathead region, had its stomach crammed with large drag- 

 on-flies, Eschna constricta, of which I easily counted thirty, besides the 

 crushed fragments of many others. 



