294 Roosevelt Wild Life Bulletin 



Lake Trout. Bean referred to the lake trout as one of the largest 

 and most beautiful of native species of the salmon family, which 

 thrives in cold, deep lakes, and is an omnivorous feeder, subsisting 

 chiefly upon ciscoes or lake herrings and other small fish; but he 

 said nothing concerning the food of young lake trout. 



It was stated that the fry were ready for distribution by the 

 Commission in March or April, the fingerlings from ]\Iay to July, 

 and that they should be planted on rocky shoals or reefs in lakes, 

 very near to deep water. 



In the report upon the work at Lake George, Dr. Emmeline 

 ^loore, one of the participants, whose special subject was "the 

 primary sources of food of certain food and game, and bait fishes," 

 states (Moore, '22) that the natural food of the very young lake 

 trout still remains a mystery. Nevertheless recommendations are 

 made by other investigators and contributors concerning the plant- 

 ing of young lake trout. Dr. Xeedham says that it must be remem- 

 bered that their first food will be water fleas and other minute plank- 

 ton ; that these are taken by mechanically straining the lake water 

 through the gill rakers, and that a large quantity of water must be 

 strained to get the hundred or so of the water fleas required for a 

 single meal. 



This appears to be a statement based upon analog}- and not upon 

 direct obser^-ation. Very Hkely, if lake trout fry were planted in 

 the places recommended, they would be compelled to feed upon the 

 small organisms mentioned or nothing. 



The recommendations to plant the young lake trout in water 

 deeper than 40 feet was not based upon any known food require- 

 ments of the young fish, but upon freedom from enemies at that 

 depth. But in the same report !Mr. Titcomb well says that it is 

 hardly natural to transfer fingerling trout from the shallow water 

 of the rearing troughs, not over six inches in depth, to water 

 fifty feet in depth, and that it is a matter of conjecture as to 

 whether they are prepared for so sudden a change in water pres- 

 sure as they will encounter at a depth of fifty feet, where they will 

 actually go after diving out of sight. 



It may be added that what they will feed upon if they remain 

 at those depths is also a matter of conjecture. 



Nevertheless Titcomb accedes to the recommendation, but adds 

 that if by strictly adhering to the revised methods of fish planting 

 the trout of Lake George do not come back as expected, the only 

 alternative will be to keep them in breeding ponds until they are 

 a year older before planting; and that in the meantime, further 

 efforts should be made to learn something about the life history of 

 the lake trout under natural conditions, from the time it hatches on 

 the spawning beds until it is a year or two old. 



Besides the uncertainty of the young fish being able to with- 

 stand the unusual pressure at a depth of 50 feet, there may be 

 some doubt whether a fingerling lake trout is capable of straining 

 the minute organisms mentioned as its prospective food in deep 

 water, in sufficient quantity to aflFord it a meal. 



