| 英文摘要 |
Catch per unit effort (CPUE) of Taiwanese distant-water longline fishery for yellowfin tuna in the Western and Central Pacific Ocean (WCPO) was standardized using the generalized linear model (GLM) and the generalized additive model (GAM), respectively. Both results indicated a stable condition for the standardized yellowfin tuna CPUE after a long term decreasing trend. The Bayesian surplus production model (BSP) was applied to assess the stock status for yellowfin tuna in the WCPO region 2 based on 6 series of CPUE indices. The results indicated that the current biomass was approaching the Bmsy, and the fishing mortality was slightly higher than the Fmsy. It is suggested that the fishing effort should not be increased, and the stock's condition and development in the fisheries should be monitored carefully.
Standardized CPUE of bigeye tuna from Taiwanese distant-water tuna longline fishery and of yellowfin and skipjack tunas from Taiwanese distant-water tuna purse seine fisheries using GLM indicated a stable increased bigeye tuna CPUE in recent years and a stable stock condition with likely slightly decreasing trend in recent years for yellowfin and skjpjack tunas. These stock conditions should be further assessed and monitored carefully. |