Cluster Analysis for Defining the Resource Distributed Area of North Atlantic Albacore Stock

應用聚落分析法解析北大西洋長鰭鮪資源的地理分布

吳繼倫(Chi-Lun Wu) ； 葉顯椏(Shean-Ya Yeh) ； 蘇偉成(Wei-Cheng Su)

《臺灣水產學會刊》 33卷1期 (2006/03) Pp. 25-34

https://doi.org/10.29822/JFST.200603.0003

摘要

長鰭鮪是臺灣大西洋鮪延繩釣漁業的傳統標的魚種。本研究使用聚落分析，依據歷年（1968-2002年）臺灣鮪延繩釣漁船在北大西洋經常作業的79個5度方格漁區中的長鰭鮪、大目鮪、黃鰭鮪及劍旗魚的釣獲率，將具有類似漁業結構的方格漁區匯整成為3個聚落並對應為北大西洋的3個亞漁區。其中，亞漁區1位於5°~15°N的熱帶海域，亞漁區2及3則分別毗鄰其上，2亞漁區間約以30°N為界。亞漁區2及3的長鰭鮪年別釣獲率明顯高於亞漁區1，而大目鮪和黃鰭鮪的年別釣獲率明顯在亞漁區1較高。本研究所得的漁區劃分結果，將可應用於北大西洋長鰭鮪釣獲率標準化研究。

關鍵字

聚落分析 ； 北大西洋 ； 長鰭鮪

並列摘要

Albacore is the traditional target species for Taiwanese longline fleet in Atlantic Ocean. Three main geographical sub-areas in North Atlantic Ocean where Taiwanese longline fleet operated frequently were produced from three distinguished clusters, which were grouped from a total of 79 and 5×5 degree statistical blocks using cluster analysis. The overall mean CPUE (no. of fish per thousand hooks) from 4 main catch species, i.e., albacore (Thunnus alalunga), bigeye tuna (Thunnus obesus), yellowfin tuna (Thunnus albacares) and swordfish (Xiphias gladius) in the 5×5 degree statistical blocks during 1968-2002 were used in the cluster analysis. The changes of temporal nominal CPUE series from 4 dominant catch species in three sub-areas were examined. Sub-areas 2 and 3, located in subtropical and temperate waters respectively, were closely related for the higher albacore CPUE. Sub-area 1, in tropical waters, had the higher CPUEs of bigeye tuna and yellowfin tuna but the lower and fluctuated albacore's CPUE. The delineation of the sub-area in this study could be used in constructing the General Linear Models for standardizing the catch rate of this stock.

並列關鍵字

Cluster analysis ； North Atlantic Ocean ； Albacore