. California fish and game. Fisheries -- California; Game and game-birds -- California; Fishes -- California; Animal Population Groups; Pêches; Gibier; Poissons. 170 CALIFORNIA FISH AND GAME 50 a: z> o I o: 40 UJ _i ei z < < 0------0 Cotch Per Angler Hour (All Inlond Blocks) o 0 Angler Days r = 0 868 _l 1 I I I I \ I I \ I L J I L 20- o to 15 5 10 < 1954 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 YFAR FIGURE 4. Comparison of partyboat catch per angler hour and effort (angler days) in the Inland Blocks, from 1954 to 1971. (Data from McKechnie and Miller (1971) and Ste
. California fish and game. Fisheries -- California; Game and game-birds -- California; Fishes -- California; Animal Population Groups; Pêches; Gibier; Poissons. 170 CALIFORNIA FISH AND GAME 50 a: z> o I o: 40 UJ _i ei z < < 0------0 Cotch Per Angler Hour (All Inlond Blocks) o 0 Angler Days r = 0 868 _l 1 I I I I \ I I \ I L J I L 20- o to 15 5 10 < 1954 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 YFAR FIGURE 4. Comparison of partyboat catch per angler hour and effort (angler days) in the Inland Blocks, from 1954 to 1971. (Data from McKechnie and Miller (1971) and Stevens unpublished.) changes aimed at increasing harvest rates would have to be evaluated with regard to tliis trade-off between numbers and average size. It is also questionable that any acceptable means can be found to increase harvest rates, considering the apparent self-regulating relationship between harvest rates, population size, and fishing effort. One obvious shortcoming in our measurement of population parame- ters is the paucity of natural mortality estimates. Intensive and sequen- tial annual measurements of natural mortalitv and, hence, survival rates will eliminate the need for approximating these values. AVe also lack understanding of the causes of the sex, size, and mortality rela- tionships. Current studies hopefully will better define these relation- ships. The environmental changes that occur due to developments such as the California Water Project, require that population parameters be precisely determined through adequate monitoring of the adult population. ACKNOWLEDGEMENTS Thomas Doyle was responsible for planning and directing tlie field portion of the tagging program. Vincent Catania (deceased) fished the gill nets. Robert J. McKechnie and Richard Penner assisted with the study. II. K. Chadwiek and Donald E. Stevens made many helpful Please note that these images are extracted from scanned page images that may have been digitally enhanced fo
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