ENEMIES OF BROOK TROUT 



seven inches long. They also feed on the natural food 

 of the fish. Wild ducks of some species are equally- 

 troublesome, and especially the mergansers, saw-bills, 

 sheldrakes or fish-ducks. 



The merganser is very destructive at all times, but 

 particularly in winter, when most of the streams and 

 lakes are frozen over. They often congregate on small 

 streams or ponds that do not freeze on account of their 

 uniform temperature. These waters are invariably 

 trout-waters. During severe winters this fish-duck 

 sometimes remains on Caledonia Creek for a month at 

 a time. At such times it is very shy, and it is almost 

 impossible to get a shot at them or keep them away 

 from the stream. Trout spawning-beds are also tempt- 

 ing spots for the fish-duck to congregate and feed. I 

 have sometimes found red-flannel flags, placed on poles 

 stuck in the bank along the stream, useful for scaring 

 the ducks away. 



Loons. 



Dr. Warren examined the stomachs of sixteen 

 loons, three of which were the red-throated species, 

 and found remains of fish in thirteen. Fall-fish, suck- 

 ers, carp, catfish, and also a brook-trout seven inches 

 long were found in the stomachs of loons killed in 

 Pennsylvania. 



On the inland lakes of New York these birds sub- 

 sist chiefly upon fish and destroy a great many. In the 

 counties of Chester, Delaware, Clinton, and Lehigh, Pa., 



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