CALIFORNIA (Cont. ) 

 U. S. Fish and Wildlife Service, River Basin Studies 



1. Northwestern California Coastal Streams 



This project was initiated to make basin wide surveys of the fish popula- 

 tions in the several streams of the north coast of California where water de- 

 velopments are proposed. The investigations have concentrated on the abun- 

 dance and' time of upstream and downstream nnovement of salmon and steelhead 

 trout. 



California Department of Fish and Game and the U. S. Bureau of Recla- 

 mation cooperating; Eel and Klamath Rivers; began June 1954, indefinite; 

 $39,000; Warren H. Nord, Leader. 



Address inquiries to: Regional Director, U. S. Fish and Wildlife Service, 

 P.O. Box 3737, Portlands, Oregon. 



COLORADO 

 Game and Fish Department 



1. Mosquito Lake Studies 



Mosquito Lake has an area of about two acres, depth of ten feet, and 

 is located on Grand Mesa at an elevation of approximately 10, 000 feet. 

 The lake is accessible by road and in an area of heavy trout fishing use. It 

 had previously been established that the lake winter -kills. Three different 

 plants of marked creel-size trout were made at different times during the 1956 

 fishing season. A partial creel census was conducted. An accurate deter- 

 mination of the fish population in the lake was obtained at the end of the 1956 

 fishing season. Data were obtained on the most suitable planting dates. Ex- 

 periments were conducted to determine the value of underwater lights as a 

 means of estimating the trout population. 



Delta County; began June 1956, to close April 1957; $500; P. T. Barrows, 

 Leader. 



Address inquiries to: Colorado Game and Fish Department, 15 30 Sherman, 

 Denver, Colorado. 



2. Parvin Lake Studies 



This is a 6-year study of a heavily fished lake in northern Colorado. A 

 complete creel census of all fishermen was obtained during 5 of these years. 

 Thus, it was possible to obtain complete information on the various experi- 

 mental plants of trout made during this time. Various species, sizes, and 

 numbers of trout were planted at varying times of the year and their subsequent 

 growth and survival followed. In addition, pertinent information was kept on 

 the fishermen and their methods. Some limnological data was collected on the 

 lake. (60 acres, elevation 8,200 ft. ) During this study period, yellow perch 

 became established in the lake and were very abundant by 1955. The study 

 was terminated in October 1955 by draining the lake, both to remove the perch 

 and to estimate the surviving trout population. 



Larimer Covmty; began May 1949, closed October 1956; $5,000; W. C. 

 Nelson, Leader; reports available. 



Address inquiries to: As in No. 1 above. 



3. Island and Eggleston Lakes Investigations 



The objectives are to determine the effectiveness of plants of marked 

 2 -inch hatchery-reared rainbow trout made in lakes of this type, and to 

 compare the returns to the creel and growth of the 2-inch plants with returns 



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