AMEBICAN MERGANSER 83 



Judging from observations made elsewhere in North America, the 

 nest is usually placed in a lioUow tree or stub. Dawson (1909, p. 759) 

 records one as liaving been found at the top of a stub one hundred 

 feet high and suggests that the young in such cases are carried to 

 the water in their mother's bill. Other observers state that the young 

 tumble from the nests into the water ten or fifteen feet below without 

 injury to themselves. The ten to sixteen pale buff-colored eggs are 

 protected by a lining of down i)lucked by the female from her own 

 breast. The young are especially good swimmers and the oarsman 

 who succeeds in catching them must be an expert. Their speed in 

 eluding a pursuer is often greatly increased by flapping along the 

 surface, something which they are able to do Avhen but a few days 

 old. When pursued, the mother is said to allow the more fatigued 

 ones to ride on her back. An instance in point is recorded by Law 

 (19126, p. 42) as follows: 



Several times the mother raised almost out of the water and dashed quickly 

 along for fifty feet or so, every chick rising and skipping after her, flapping 

 their little wings and paddling the surface of the water with their little feet. 

 After three of these spurts the youngsters seemed to tire, and one climbed on its 

 mother's back, and soon several had done so, and rode securely there as long 

 as they were in sight. 



Swarth (1911, pp. 39-40) records an interesting method of obtain- 

 ing food as observed in Alaska, which has also been recorded for the 

 Red-breasted Merganser (C. W. Townsend, 1911, p. 343). The former 

 writes : 



I was concealed in the shrubbery at the water's edge examining a large 

 flock of ducks for possible rarities, when a dozen or more mergansers (M. ameri- 

 canus and M. serrator) began swimming back and forth but a very short dis- 

 tance from my blind. They swam slowly, with neck outstretched, and with 

 the bill held just at the surface of the water, and at a slight angle, so that the 

 head was submerged about to the level of the eyes. The water was evidently 

 filtered through the bill, as a slight "gabbling" noise was quite audible, and 

 obviously something was being retained as food, though just what it was I 

 could not tell. 



As one of its vernacular names (fish duck) signifies, the regular 

 diet of the American Merganser is made up chiefly of fish, which it 

 devours in great quantities. The gullet of an individual killed at 

 Los Bafios, Merced County, February 19, 1912, contained five carp 

 about four inches in length. If carp were the only kind of fish eaten 

 this would be considered a useful bird; but the merganser is also 

 known to eat salmon and trout fry. Mr. W. H. Shebley, superin- 

 tendent of hatcheries for the California State Fish and Game 

 Commission, (in letter) says: "The sawbill or fish duck is very 

 destructive to trout and other fish. I have killed individuals on our 

 trout ponds gorged with trout so that they were unable to swallow 

 another one. "We consider them one of the worst of the fish-eating 

 birds." 



