REPORT OF COMMISSIONER OP FISH AND FISHERIES. XXI 



BIOLOGICAL INQUIRIES. 



The work of the division of scientific inquiry has been of more than 

 usual interest during the past year. Several important investigations 

 have been inaugurated, and those already in progress have been com- 

 pleted or continued. 



In July, 1898, a systematic survey of the biological and physical 

 conditions of Lake Erie vras begun and has been carried on with grati- 

 fying success. The commercial value of the fisheries of the Great 

 Lakes and the magnitude of the fish-cultural operations necessary to 

 maintain the supply of food-fishes make it important that all of the 

 conditions which affect fish life be carefully studied, especially that 

 future fish-cultural efforts may obtain the best results. The investiga- 

 tion was begun in Lake Erie, with headquarters at the station of the 

 Commission at Put-in Bay, where the hatchery building could be used 

 as a laboratory and the other facilities of the station, including a 

 steam launch, could be utilized; furthermore, the region affords excel- 

 lent natural advantages for pursuing the studies iudicated. Prof. 

 Jacob Eeighard, of the University of Michigan, was placed in direct 

 charge of the work, and was assisted by a corps of specialists, consist- 

 ing of representatives from various institutions of learning and from 

 the staff of the Commission. The summer was devoted to a study of 

 the fishes and of the minute animals and plants which influence the 

 movements and distribution of fishes, and the results were of such 

 value that the investigation will be continued and its scope enlarged 

 as much as possible. 



The biological surveys of the interior waters of the Northwest have 

 been continued under the direction of Dr. B. W. Evermaiin. The inves- 

 tigations during the season of 1898 chiefly concerned lakes Chelan, 

 Kootenay, and Coeur d'Alene, and were, in a measure, preliminary to 

 determining the advisability of more exhaustive inquiries in future. 

 Lake Chelan, in the State of Washington, one of the largest bodies of 

 fresh water west of the Mississippi, and Lake Kootenay, in British 

 Columbia, are two important sources of the Columbia River. The 

 investigations regarding them embraced a study of their general fish 

 fauna, and were also for the purpose of determining the presence in their 

 waters of the blueback salmon or red-fish in connection with the studies 

 of the salmon in the Columbia River basin, which have been carried on 

 for some years by the Commission. The fishes of Lake Chelan have never 

 been studied, and, though it is known to contain 8 or 10 species, the 

 red-fish probably does not occur in it. IS^o satisfactory evidence could 

 be found of the presence of the large red-fish in Lake Kootenay, but the 

 small variety occurs in considerable numbers in the Kootenay system, 

 and it is reported as spawning in streams in that region tributary to the 

 Columbia. In Lake Coeur d'Alene, Idaho, it was desired to ascertain 

 the resultsof plants of white-fish made by the Commission. No positive 

 information was obtained, but the fishery resources of the lake are such 

 as to warrant a further comprehensive study of its conditions. 



