BARROWS GOLDEN-EYE 329 



This is the case in autumn or winter, but on the breeding grounds, where the two 

 kinds almost never mingle, it is a different matter. 



From the somewhat sketchy nature of our information on this duck it seems that 

 the intimate traits are very similar to those of the Golden-eye save only the breeding 

 habits. The voice is the same as far as the female is concerned but the spring call of 

 the male has not often been heard, and it seems likely from what Allan Brooks has 

 told me that it is a much less powerful sound, for he has difficulty in hearing it, as do 

 others who have had an opportunity to watch these ducks before the nesting season. 



The wing-whistle is like that of the true Golden-eye, but not so loud (Riemschnei- 

 der, 1896; Millais, 1913) and the flight is just the same. 



Association with other Species. Wherever found in winter on the Atlantic 

 coast this duck is mixed in with Common Golden-eyes, but almost never in the com- 

 pany of other ducks. On its breeding grounds, of course, the Common Golden-eye 

 seldom if ever occurs. In Iceland, on Lake Myvatn, where large numbers nest iu 

 holes in the rocks, their eggs are not infrequently mixed with those of the Red- 

 breasted Merganser (Hantzsch, 1905). One nest described by Shepard (in Baird, 

 Brewer, and Ridgway, 1884) contained four eggs of this species which were being 

 incubated by a female Merganser. 



Food. The Rocky Mountain Golden-eye lives on fresh- or salt-water mollusks 

 and crustaceans and is very fond of small crayfish which lurk under large stones in 

 shallow water. While hunting these they work rapidly along the shore, diving every 

 few minutes to probe under the edges of the large stones. The crayfish are brought 

 to the surface to be swallowed, but this is not so with the small shellfish. By the end 

 of winter the feathers on the forehead are generally worn off through rubbing against 

 the stones while foraging for crayfish (Munro, 1918). The same observer (Munro, 

 1923) found that in November on Henderson Lake, Vancouver Island, these ducks 

 ate a large number of sock-eye salmon eggs. They came during daylight hours and 

 fed along sandy bottoms where immense numbers of salmon were depositing their 

 eggs. Out of twenty birds shot and examined, all, or at least all that had had time 

 to feed, contained salmon eggs; in one case as many as three hundred. 



A single stomach from Barr, Colorado, contained some musk-melon seeds and oats, 

 evidently waste material, a fly larva and several earthworms. One examined by Dr. 

 Bernard Gilpin of Nova Scotia was filled with marine univalves of four species 

 (Forest and Stream, vol. 10, no. 5, p. 75, March 7, 1878). The indications are that 

 the food is similar to that of the American Golden-eye. 



Courtship and Nesting. This Golden-eye selects deep, clear lakes during the 

 nesting season, the same sort of places where the Red-breasted Mergansers are seen, 



