492 



U. S. BUREAU OF FISHERIES 



made at La Crosse, Wis., the Potomac River, and the Lakeland ponds. A fine 

 display of adult brook trout and rainbow trout was received from the White 

 Sulphur Springs (W. Va.) station, and the Bozeman (Mont.) station contributed a 

 small number of adult grayl ng and black-spotted trout. 



During the spring considerable trouble was experienced from the parasite 

 Ichthyophthirius in the aquarium tanks, and before its ravages could be checked 

 it occasioned a heavy loss of fish. It was finally eradicated through the use of 

 strong solutions of lime water in the tanks, and by the end if June all surviving 

 fish were well on their way to recovery. 



Part 2.— DISTRIBUTION OF FISH AND FISH EGGS 



[E. C. Fearnow, Superintendent oT Fish Distribution] 



The 5,301,862,583 fish and fish eggs comprising the net output of 

 the hatcheries and rescue stations operated by the Bureau of Fislieries 

 during the fiscal year 1925 were widely disseminated, distributions 

 being made in practically every State in the Union, the Territory of 

 Alaska, and the Canal Zone. Approximately 90 per cent of the out- 

 put consisted of commercially important fish, such as the salmons, 

 whitefish, pike perch, shad, yellow perch, lake trout, cod, pollock, 

 haddock, flounder, buffalo fish, and carp. Such species are planted 

 in waters in the vicinity of the hatcheries or near the source of egg 

 supply, with the exception of a comparatively small number used 

 for stocking waters where natural conditions appear to be favorable 

 for the development of new fisheries. They are not supplied to ap- 

 plicants for the stocking of private waters. Under the head of com- 

 mercial species are included the many food fishes annually salvaged 

 from overflowed areas along the Mississippi River. 



Among the important species propagated for stocking waters of 

 the interior are the brook trout, rainbow trout, black-spotted trout, 

 largemouth black bass, smallmouth black bass, rock bass, sunfish, 

 crappie, and catfish. This branch of the bureau's work brings it 

 into close relation with the general public, as is evidenced by the 

 large number of applications submitted every year. In the course 

 of the fiscal year 1925, 10,400 applications were filled and the bureau 

 made about 1,800 plants in public waters on its own initiative, 

 bringing the total number of assignments to 12,200, or 200 more than 

 were made in 1924. The Izaak Walton League and various fisheries 

 organizations during the past year submitted an unusually large 

 number of applications, and in view of the large membership inter- 

 ested in the distribution of fish the allotments were liberal. 



Summary, by species, of distribution of fish, fiscal year 1925 



