Spawning-recruitment relationship of the largehead hairtail Trichiurus japonicus in the Yellow sea
1997
Liang, Z. (Seikai National Fisheries Research Inst., Nagasaki (Japan)) | Otaki, H.
In this report, we studies the reproductive relationship of the largehead hairtail, Trichiurus japonicus in the Yellow Sea. The yearly indices of number of spawners were obtained from the catch in number by ages in each year from 1959 to 1970, using the sex ratio by age, maturity rate by age and by year, and number of eggs per female by age and year. According to the mesh selectivity of pair-trawl net, the age of first capture was 2 age. The spawner-recruitment relation ship of largehead hairtail can be represented by the number of 2 age and the spawner in two years ago. The spawners were divided into the group more than 4 age which the original main spawning group and the group of 2 and 3 ages which newly joined spawning because of decrease of population especially older ages. In the results, although the relationship between the spawner of 2 and 3 ages and the recruitment was not clear, a clear proportional relationship was recognized between the spawner more than4 age and the
Показать больше [+] Меньше [-]