58 U. S. BUREAU OF FISHERIES. 



that originally teemed with game fishes have become practical iy 

 depleted, while others would become so were it not for the etl'ort.- 

 made by the bureau and the various State fisheries departments to 

 keep up the supply. This depletion of fish life, especially of the 

 brook trout, in so many of the streams of the country has increased 

 the demands upon tlie bureau for eggs and fry of this species out 

 of all proportion to its available supply. 



In connection with its work of propagating the brook trout the 

 bureau has found it necessary to purchase from commercial dealers 

 the bulk of the eggs used for stocking its hatcheries. In many cases 

 eggs from this source are of poor quality and the fry resulting ivom 

 them lack the vitality inherent in fr}- derived from wild fish. In view 

 of the situation the bureau has been endeavoring for the past year 

 or two to establish, on a promising site at York Pond, N. H., a 

 plant capable of producing sufficient brook-trout eggs to fill its 

 needs. Work on this plant is being pushed to completion as fast 

 as the available funds will permit. 



Other fishes for which large demands are annually made are the 

 black bassefe, both the largemouth and the smallmouth species. Witli 

 the present facilities for their production it is practically impossible 

 to produce them in sufficient numbers to meet the requirements, and 

 the urgent need for the extension of this branch of the work is 

 clearly apparent. 



ROCKY MOUNTAIN TROUT STATIONS. 



This important group is composed of eight stations and substations, 

 located in the States of Colorado, Montana, South Dakota, Wyoming, 

 and Utah. The year's work of the group was most successful, 

 especially as regards the propagation of the black-spotted trout, the 

 output of which was more than five times as large as that of the 

 preceding year. The total output of these stations in eyed eggs and 

 fry during 1923 aggregated 22,364,540, the species handled includ- 

 ing black-spotted trout, brdok trout, rainbow trout, and small num- 

 bers of Loch Leven and steelhead trout. 



BOZEMAN (MONT.) STATION AND SUBSTATIONS. 

 [W. T. Thojipson, Superintendent.] 



Fish-cultural work at Bozeman station and its auxiliaries con- 

 sisted in the propagation of brook, rainbow, black-spotted, and lake 

 trout and the steelhead salmon. The majority of the eggs handled 

 were taken in outside fields, only 1,610.000 being secured in local 

 waters, while the year's output from this o-roup of stations aggre- 

 gated nearly 2,000,000 fingerling fish and 1,389,000 eyed eggs, the 

 latter, at the request of the National Park Service, being deposited 

 in waters of Glacier Pai'k which it would be impossible to reach 

 with fry owing to their inaccessible location. 



BOZEMAN (MONT.) STATION. 



During the year the Bozeman hatchery received from outside 

 sources 1,285,000 brook-trout eggs, of wdiich 250.000 were purchased 

 from a commercial dealer. The remainder was contributed by the 



