| 英文摘要 |
CPUEs of Atlantic white marlin (Tetrapturus albidus) and blue marlin (Makaira nigricans) caught by Taiwanese longline fishery for 1968-2004 were standardized using a General Linear Model (GLM) and Delta lognormal model. The GLM model and Delta lognormal model with Year, Fishing season, Area, and Target species main factors, and with fishing season and area interaction for the period from 1968 to-2004 were carried out for the two hypotheses on the stock structure, one total Atlantic stock and separate north and south Atlantic stocks. Standardized CPUEs of white marlin show a decreasing tendency from 1974 to 1977, maintain in a stable level from 1977 to 1990, reach at the lowest level in 1991, and then increase to the highest level in 1994 and decrease from 1994 onwards. Standardized CPUEs of blue marlin show a decreasing tendency from 1968 to 1987, which then increase to the level of the early 1970s and then decreasing again from 2001 onwards. |