FORTY-FIRST BIENNIAL REPORT 103 



Curtis, Brian 



Report of the Activities of the Biological Staff of the Bureau of Fish Con- 

 servation for the Fortieth Biennium, July 1, 1946, to June 30, 1948. 



Abstract : Describes the activities of the staff. Printed in large part in 

 "Fortieth Biennial Report of the Division of Fish and Game" as part of the report 

 of the Bureau of Fish Conservation. 



Douglas, Philip A. 



Rough Fish Control in Elizabeth Lake Canyon Drainage, Los Angeles County. 

 Submitted December 28, 1949. 21 pp., including 13 figures, 6 tables, 1 graph, plus 

 Appendix A and 2 sketch maps. 



Abstract : A decline in the fishing success for largemouth black bass, bluegill, 

 erappie, catfish in the Elizabeth Lake Canyon drainage, Los Angeles County, 

 necessitated a study of causative factors. 



A heavy population of greaser blackfish Ortliodon microlepidotus (Ayres) 

 was found to be present in the four major bodies of water in the drainage, and 

 stomach analyses indicated that they were of little forage value to the largemouth 

 black bass in the area. 



Plans were laid for a 2-day treatment program distributing 1,600 pounds of 

 cube root-33 percent rotenone, over 160 surface acres or 655 acre-feet of water, or a 

 concentration of 0.90 p. p.m. of the chemical was used. (A high concentration of 

 rotenone was used due to the alkaline waters involved.) The blackfish was found 

 to be the most susceptible to the chemical, appearing in distress within thirty 

 minutes following application of the rotenone. An estimated kill in waters treated 

 was 605,601 rough fish (95 percent) and 26,017 game fish (5 percent). One lake 

 had a natural kill October 12, 1949, and no new fish appeared following treatment. 



A restocking program for 1950 for the public lakes is based on a comparative 

 basis of percentage compositions by species of the original stocking between 1938 

 and 1945 of Lake Hughes, and the percentage composition of the same fish popu- 

 lation estimated following the chemical treatment of November 26, 1949. 



From the above figures the following was noted : Largemouth black bass 

 decreased slightly ; bluegill decreased considerably ; catfish increased moderately ; 

 and black erappie increased considerably. 



A stocking program for the public waters has been proposed for 1950. 



p]vans, Willis A. 



A survey of the city park lakes of Los Angeles in relation to their proposed 

 use for children's fishing recreation, Los Angeles County. Submitted March 20, 

 1949. 22 pp., including eight figures and five maps. 



Abstract : A survey of the five Los Angeles City park lakes was made during 

 January, 1949, to determine their adaptability to a children's fishing program. Thi*ee 

 out of the five lakes are believed suitable for development and use within the year. 

 The other two may be utilized as brood ponds to serve the other three. Fishing 

 should be carried on under as natural conditions as possible. Physical and biological 

 characteristics of the individual lakes are briefly discussed and recommendations 

 for fish management in each presented. 



Fraser, J. C. 



Supplementary Report No. 1 on the Emigrant Basin Flow Maintenance Dam 

 and Stream Improvement Program (Wildlife Conservation Board Project No. 16), 

 Tuolumne County. Submitted January 6, 1950. 23 pp., including three tables, 1 

 photograph. 



Abstract : Describes certain subprojects, including 4 new ones, and gives a 

 revised status of subprojects in this program based on field sui'veys made in 1949. 



1949 Lake Tahoe Party Boat Catch Records, Placer/El Dorado Counties. 

 Submitted January 9, 1950. 8 pp., 3 tables. 



Abstract : Seven guide fishermen operated from California ports in 1949, 

 making 357 trips with a total of 587 anglers. Catch consisted of 1,009 mackinaw, 

 6 rainbow trout, and 5 brown trout, total weight of all trout 3,433.5 pounds ; average 

 weight of all trout 3.4 pounds ; average catch per angler 1.7 ; average catch per 

 hour .37 ; average catch by weight per angler 5.8 pounds. 



