| 英文摘要 |
This study was tried to understand the stock assessment and by-catch of anchovy fisheries with its impact on commercial resources in the waters of Taiwan. The data of anchovy catch, fishing effort, environmental and biological information in Fang-laio waters were collected by reference and historic sample since 1980. And then build the operating model of Surplus Production model was built to estimate resource and maximum optimum size and production of anchovy affected possibly by environment and fishing stress in the southwest water of Taiwan.
The result show species and CPUE change with different season in southwest and northeast waters of Taiwan. The dominant species of Encrasicholina punctifer in these two waters was changed by season. In Tam-Shui waters, the dominant species were also exchanged from Engraulis japonicus to Encrasicholina heteroloba and then Encrasicholina punctifer. According to 16 articles related to the study of anchovy biology and fishing ground, the body length, weight, growth rate and VBGE were collected in this study.
Wavelet model analysis show that catch of anchovy have 1.3 year variation and 4~5 years cycle in 1980~1990. Mutual wavelet model analysis show the anchovy catch was high correlation with SST in 1980~1987. After 1988, catch show the 1~2.3 year positive correlation cycle with river flow. For the surplus production analysis, CPUE and fishing stress was reached to the level of overfishing and overfished in the 1990 decades. Based on the ratio of F/FMSY |