506 U. S. BUEEAU OF FISHERIES 



The development of a brood stock and the raising of larger fish 

 for planting are both largely dependent upon the availability of 

 suitable water. This problem is particularly acute in California, 

 where practically all the water at low elevations is stored or diverted 

 for irrigation. 



An excellent site for this type of work has been developed at Hot 

 Creek, in Mono County, which is on the eastern slope of the Sierra 

 Nevada Mountains. Warm springs arise along the course of this 

 stream which have a constant temperature of 60° F. and a flow of 

 about 30 second-feet. The gravel bed of the stream is covered with 

 water cress and other aquatic plants. Fish food is abundant in the 

 form of the amphipod Gcvmmarus raniellus^ which is present in 

 numbers up to 1,000 per square foot of stream bottom. The terrain is 

 such that ponds can be constructed and maintained at low cost. Dur- 

 ing the latter part of the year two experimental ponds were con- 

 structed at this place. Due, however, to a heavy fall of snow in 

 December, it was impossible to stock these ponds during the present 

 year. There is sufficient water at Hot Creek to allow of the estab- 

 lishment of both brood stock and fingerling ponds. 



Two streams have been selected for the study of the life history 

 of the steelhead, including the study of the migratory movements of 

 the young fish through marking and by monthly sampling in the 

 upper parts of the streams and in the lagoons. This work has been 

 somewhat hampered by exceptionally heavy rainfall and the con- 

 sequent flooding of the streams, but work is also being done on the 

 migration, growth rate, and egg production of the adult fish through 

 tagging. 



LIMNOLOGICAL INVESTIGATIONS IN THE NATIONAL PARKS AND FORESTS 



Following conferences early in the year 1931 the Bureau of Fish- 

 eries announced recognition of its responsibility in stocking the 

 public domain with food and game fishes, and plans were made for 

 active cooperation with the Forest and Park Services to fulfill that 

 responsibility in a competent manner. As its specific duties the 

 bureau proposed to undertake scientific surveys of forest and park 

 waters as a basis for drafting a national program of fish planting, 

 and plans were made for the Forest and Park Services to cooperate 

 with the bureau in the planting of fish in accordance with an orderly 

 plan of stocking. To carry this out the bureau proposed to or- 

 ganize in each of the national-forest areas of the United States in- 

 vestigations under a competent biologist who should conduct and 

 suj)ervise stream and lake surveys in the waters of the public domain, 

 and who should develop therefrom a rational policy of stocking such 

 waters with fish. 



A preliminaiy survey of the lakes and streams of Wasatch Na- 

 tional Forest in Utah was conducted during the summer of 1930, and 

 in June, 1931, a permanent investigator of the bureau. Dr. A. S. 

 Hazzard, was placed in charge of stream surveys in the intermoun- 

 tain region. 



The primary purpose of these studies is to collect basic physical, 

 chemical, and biological data on the lakes and streams of these areas 

 and to interpret these data in the form of systematic stocking pro- 



