Further Calibration Incorporating with Yearly Changes of Biomass and Surplus Production from Results of Virtual Population Analysis for North Atlantic Albacore

應用年級群分析結果配合生物量和余量生產的年度變化對北大西洋長鰭鮪系群狀態做進一步的評估

許建宗(Chien-Chung Hsu)

《臺灣水產學會刊》 23卷3期 (1996/09) Pp. 165-180

https://doi.org/10.29822/JFST.199609.0001

摘要

本研究於1991、1992及1993年之夏季於本省東北部沿海進行聲探計測，利用自行開發之聲探影像處理系統(EIPS)擷取與魚群內、外部結構有關之說明變量，將實驗期間所擷取之2,031組魚群說明變量進行主成份分析及群集分析，藉以瞭解魚之群集特性。主成份分析之結果顯示，魚群結構之年度別及日夜別差異不若地域別者顯著，分佈於淺水域之魚群群集密度較深水域者低，而且在等深線20米及70米附近有較高之魚群出現率。群集分析之結果顯示，1991年之探測海域可依魚群群聚特性的不同區分為4個聲訊族群，1992及1993年則各可區分為5個聲訊族群。各個聲訊族群分別佔據不同的海域區塊，且棲息之魚群有顯著的差異，其中兩個區塊主要棲息魚種為鱹、魩及珊瑚礁魚類，另二及三個區塊之主要棲息魚種則為鰹、鰺、白帶魚及鎖管等，此外，各區塊之水深、底質特性也各不相同。

關鍵字

大西洋長鰭鮪 ； 漁獲能率 ； 年度余量生產 ； 資源量指標

並列摘要

Hydroacoustic data collected from the summers of 1991,1992 and 1993 were analyzedto characterize fish shoals in the coastal waters of northeast Taiwan.The computer softwarewere designed to measure descriptors related to internal and external characteristics of theshoals.A total of 2,031 sets of shoal data were analyzed by the principal components andthe hierarchical classification methods.The annual and diurnal differences were less significantthan differences among depths.Relatively high occurrence of fish shoals was found arounddepths of 20 m and 70 m.Fish shoals at depths less than 45 m deep were of lower echointensity than those in deeper waters.Four acoustic populations were recognized in 1991and five in 1992 and 1993,which occupied different regions of the study area,likelyrepresenting different ecological zones.Two regions were dominated by anchovy,sardineand reeffishes.The other two or three regions were dominated by skipjack,horse mackerel,hairtail and squid.The sedimental and topographical characteristics were significantly differentamong the four and five regions.

並列關鍵字

Atlantic Albacore ； Catchability ； Annual Surplus Production ； Abundance Index