544 BULLETIN OF THE BUREAU OF FISHERIES. 



available the insect food appears to be more or less neglected, particularly by the 

 larger fish. 



The diet of the trout, however, varies not only with the season but with the age 

 of the fish. The seasonal variation, however, may be one of convenience, but that of 

 different stages of growth is influenced by suitability. 



The first food of trout fry consists largely of minute crustaceans and small ineect 

 larvae, such as Chironomus, black fly, etc. ; and that of the fingerling, of larger insect 

 larvse, worms, and small insects, which diet, however, is not exclusive and is controlled 

 more or less by the habitat and environment. 



The regular food supply of the adult trout of Rangeley Lakes, aside from the 

 insects and more or less accidental or incidental animals, was formerly, without much 

 doubt, the small fishes occurring there, including its own young and eggs to some extent. 

 The blueback trout was believed by the late Commissioner Stanley to have been the 

 main dependence of the large trout and that it was due to the blueback that the trout 

 attained its large size. 



J. Parker Whitney," to whom reference has previously been made, said that in 

 December and January there was a notable scarcity of live bait, meaning small fishes, 

 and that in February and March it was very difficult to find. "Yet," he said, "the 

 trout are seldom empty of small fry or chubs, and it is quite likely that the trout root 

 them out of the mud. This is indicated by earth and often lumps of clay found in 

 their stomachs." He stated that he had caught large trout often with a small hand- 

 ful of clay balls in their stomachs. "In winter," he continued, "the contents of their 

 stomachs are quite miscellaneous — glutinous ground feed, chubs, varieties of small fry, 

 rarely bluebacks, suckers, and in a few instances I have found whole clams in shells up 

 to 3 inches in length." 



If the disappearance of the blueback deprived the Rangeley trout of an important 

 food supply, it has been more than compensated for in the smelt which was introduced. 

 In the Rangeley Lakes the smelt does not attain a large size, has multiplied tremendously, 

 and is locally available as food for trout from one end of the year to the other. 



Regarding the smelt, Mr. Whitney wrote (loc. cit.) that it was apparently an admir- 

 able food for the salmon and trout and in the spring seemed to be their principal food, 

 as their stomachs seemed to be crowded with them, and that he had repeatedly 

 observed from 50 to 70 in the stomach of a single large trout. 



Feeding time. — The feeding habits of trout are influenced by both internal phys- 

 iological and external physical conditions, so that it does not feed at all times of the 

 year or the day. While it takes food readily up to the breeding time, breeding fish are 

 not much inclined to feed. The postnuptial wasted condition of the fish would naturally 

 impel it to recuperate by feeding, but at that time food is scarce. This, however, is 

 compensated for by the cold water making the fish more or less sluggish or dormant, 

 when there is little metabolism and little or no food required. But these two forces are 

 contending, as it were, and the fish, therefore, will eat when there is anything to eat, 

 but they can get along without it. The warming of the water and other physical 

 changes stimulate them to activity and need of food. The foregoing statement, however, 

 should not be construed to mean that trout do not feed in the winter time when food is 

 available, for it is well known that they are readily taken by fishing through the ice, 



<> Forest and Streain, Nov. 24. 1900. 



