英文摘要 |
The standardized CPUE of swordfish caught by Taiwanese and Japanese longline fisheries in the Indian Ocean roughly revealed decreasing patterns before 1990, thereafter Taiwanese CPUE series was relatively stable and Japanese CPUE series decreased continuously. Based on the preliminary results of ASPM, there is probable overfishing of the swordfish stock in Indian Ocean in recent years while the stock currently appears not to be in an overfished state. A total of 39 head and 86 spine samples of swordfish in the Indian Ocean have been collected from observer program.
The standardized CPUE of southern bluefin tuna caught by Taiwanese longline fishery revealed a relatively stable patter before 2003. High CPUE in 2004 and 2005 might be resulted from decreased vessels for SBT and stable catch of SBT. As the results, the standardized CPUE revealed a relatively stable trend than nominal CPUE.
Taiwanese catches of oilfish and escolar mainly occurred between March and June. The proportion of Oilfish catch was substantially higher than escolar, even higher than bigeye tuna, yellowfin tuna or albacore. oilfish and escolar were mainly caught around the southern waters of Madagascar and the southern and southeastern waters of South Africa. In the temperate water, the catch of oilfish was obviously higher than escolar. In the tropical water, the catches of oilfish and escolar were low and the proportion of escolar was higher than oilfish. |