556 U. S. BUREAU OF FISHERIES 



fields in this district. At this point collections of Loch Leven trout 

 eggs in excess of 15,000,000 are available annually for maintaining 

 the local supply and for shipment on an extensive scale to other 

 parts of the country. The main station at Bozeman experienced a 

 highly successful year, producing an output requiring 25 trips of the 

 bureau's railroad cars to distribute, in addition to 12 loads carried 

 by tank trucks. Operations at the Miles City (Mont.) substation^ 

 constituting the largest pond fish cultural unit in the Northwest, are 

 directed jointly by the Bozeman station and the Montana Fish and 

 Game Commission. During 1932 this imit produced over 600,000 

 pond fish, including black bass, crappie, sunfish, catfish, and minor 

 species. Its efficiency was materially increased by the construction 

 of a new water supply ditch Iji miles in length. 



Included for administrative reasons within the Rocky Mountain 

 group is the Crawford (Nebr.) unit, which is gradually expanding its 

 production of pond fish by the establishment of ponds on the Fort 

 Robinson Military Reservation. The Spearfish (S. Dak.) hatchery, 

 which serves the Black Hills region, is now concentrating on the pro- 

 duction of larger sized fish in preference to increased numbers. The 

 work at that point was hampered by the virtual disappearance of the 

 hatchery spring water supply during the early spring. By resorting 

 to various expedients the crop of fish was cared for and on resump- 

 tion of the normal flow it became evident that the season's output 

 would not be seriously affected. 



Second only to the Bozeman station is the Leadville (Colo.) 

 hatchery with its two auxiliaries at Creede and Crystal Lake, near 

 Leadville, the last named now being in course of establishment. 

 The constructions to date have consisted of a dwelling, service build- 

 ings, and a water-supply system, preparatory to the installation of 

 rearing ponds. A lake on the property has been stocked with 75,000 

 brook trout fingerlings. The main station at Leadville made its 

 usual field collections of brook and rainbow trout eggs, amounting 

 close to 8,500,000. The efficiency of the Creede substation has been 

 materially increased by the provision of a new water supply adequate 

 for the full capacity of the hatchery. 



Rainbow-trout operations at the Saratoga (Wyo.) station were 

 hampered by the recent draining of the Pathfinder Reservoir, which 

 in the past has yielded millions of eggs of this species. Satisfactory 

 egg collections were secured for the Springville (Utah) station but 

 severe epidemics occurring during the fry stages of the resulting fisk 

 caused a very heavy mortality among all species of trout on hand. 

 An investigation traced these losses to a bacterial infection, which 

 arose apparently from the unprotected water supply. Various 

 expedients, including improvement of the spring source and the use 

 of city water, are being planned for in an eft'ort to avert this difficulty 

 in future. The Springville station has now built up a sufficient stock 

 of brood rainbow trout to enable it to ship a number of eggs to other 

 points. As the season for the propagation of black-spotted trout in 

 the Yellowstone Park extends through June into the late summer, a 

 report on the year's operations must necessarily include only part of 

 the work performed during any given season. Egg collections in this 

 field during the spring of 1932 amounted to 17,500,000, exceeding the 

 take of the two previous years. Experimental lots of grayling eggs 

 were handled also. An extensive series of rearing pools in course of 



