The occurrence of the mesopelagic shrimp, Funchalia taaningi Burkenroad, 1940 (Decapoda：Penaeidae) in the waters adjacent to Taiwan, with some comments on the taxonomic status of F. sagamiensis Fujino, 1975

Abstract

本研究在小琉球外海投放一組表層人工浮魚礁，爲了解主要聚集魚種的分布特性，利用聲探技術及漁獲試驗在浮魚礁週邊海域進行計測。結果獲得六種主要魚種的分布情形，經聲探回訊積分法、信號特信篩選法及集群分析法等分析結果，確認蝶魚及單棘魨洄游於礁體表層附近，但沒有明顯的日夜變化情形；雙帶鰺白天洄游於礁體附近100公尺以內，水深30-50公尺的海域，入夜後聚集魚群明顯減少；鰹鮪魚群白天分布於約800公尺以內水深50公尺以淺的海域，入夜後有離開礁體的現象；皮刀魚群的分布則較廣，白天時，在礁體附近的皮刀魚群聚集於離礁體約550公尺以內水深50-80公尺的海域，但入夜後則消失不見。浮魚礁周邊海域的聲探計測結果，顯示本組人工浮魚礁具有相當良好的聚魚效果。此外，利用聲探技術評估人工浮魚礁週邊海域的魚群群聚特性應屬可行。 An experimental surface fish aggregating device(FAD)was deployed in the coastalwaters off southern Liuchiu Island,Taiwan.The acoustic survey and fishing experimentswere carried out to investigate fish aggregation patterns around the surface FAD.Theacoustic signals of six main species were obtained in this experiment.The results of echointegration,signal feature analysis and cluster analysis showed that butterfly fish(Chaetodon speculum)and Unicorn leatherjacket(Alutera monoceros)aggregated in thenearby area of the surface FAD and had no obvious diurnal change.Yellow-finned runner(Elagatis bipinnulatus)distributed themselves with a reach of 150 m from the surface FAD,at depths of 30-50 m in daytime,and almost disappeared in nighttime.Skipjack tuna(Katsuwonus pelamis)and yellowfin tuna(Thunnus albacares)aggregated with a reach of800 m from the surface FAD,and in the surface area of 50 m depth in daytime.Duringnighttime,Skipjack and yellowfin tunas seemed disappear from the FAD zone.Moonfish(Lampris regius)schools had an extensive range from the vicinity of the FAD.In thenearby area of the FAD,moonfish schools aggregated with a reach of 550 m from the FADat depths of 50-80 m,and disappeared in nighttime.The fish aggregation effect aroundthe FAD was quite significant.And the results show that the application of acoustic methods used to investigate the distribution patterns and biomass of fish aggregating in theFAD zone should be feasible.