東京滿山 문치가자미 Limanda yokohamae(GUNTHER)의 資源量 變動의 解析

Population Dynamics of Mabled sole Limanda yokohamae(GUNTHER) in Tokyo Bay, Japan

Population dynamics of Mabled sale Limanda yokohamae(GUNTHER) in Tokyo bay. Japan has been studied by virtual population analysis (VPA) for multi cohort and experimental fishing. Based on the biological data, the present parameters of the Limanda yokohamae stock at the Tokyo bay, Japan were estimated as follows: natural mortality coefficient(M) were 0.313 for male and 0.250 for female, terminal fishing motality coefficient(F) were 2.190 for male, and 0.798 for female, rate of exploitation(E) was 30% to 50%. From the result of virtual population analysis for multi cohort, the population size were estimated from 3,5000,000 to 9,200,000 fishes, according to the result of experimental fishing, estimated stock size were 2,400,000 to 8,700,000 fishes. Stock size difference of the two methods were about two times in 1987, however, other years has been showed from 0.8 to 1.5 times. Both method has been showed same increase and decrease tendency of the c. p. u. e. and catches. From the isopleth diagram plot by Beverton and Holt's yield per recruit, the catches could be increase two times for female, 1.3 times for male than present aspects by the fishing management. And further, as reducing fishing effort, extension of mesh size and rising the length at first caputre, are reasonable in order to manage the stock at the optimum level.