| 英文摘要 |
We have understood many subjects more clearly after our study from 2003 to 2005.There are including resource variation of ocean sunfish, and age and growth, migration route and habitat of sharptail mola. Many people care that the numbers of catch in sharptail mola in 2005 are lower than before. Then we have focused on two subjects, migration route and resource variation of ocean sunfish, in this year. One PAT tag has been used to estimate the migration route of sharptail mola at November 8, 2006. The total length and weight of marked fish is 131 cm and 80 kg. The tag recorder will release and start to transmit data at February 11, 2007.
The total numbers of catch in sharptail mola are 3,649 that are more than 3,060（2004） and 1,115（2005） from January to October in 2006. The catch numbers of January in this year are most from 2003 to 2006. The average weight per fish is 90.15kg in 2006. It is lightest from 2003 to 2006. The average weight of May is still the heaviest same to before. Fishery data show us that the catch have decreased in March, April , May and increased in September, October, November year by year. There is an opposite condition in average weight per fish. If the fishery data can reflect the age structure of population directly, we should use this fish resource more carefully. |
