Age and Growth of the White-Tongued Crevalle,Uraspis Helvolus,in Suao Coastal Waters of northeastern Taiwan

臺灣蘇澳沿岸海域沖鲹之年齡與成長

邱萬敦(Wann-Duen Chiou) ； 陳哲聰(Che-Tsung Chen)

《臺灣水產學會刊》 20卷2期 (1993/06) Pp. 125-134

https://doi.org/10.29822/JFST.199306.0005

摘要

本研究旨在探討我國在印度洋作業之大目流網、鮪延繩釣所捕獲長鰭鮪之體長組成及生殖腺指數分布，並析明本魚種之最小成熟體長、性比、孕卵數等有關之生殖生態。本報告所採用之長鰭鮪生殖腺樣本主要係採自1987年10月～1990年3月，於高雄前鎮魚市場及鄰近加工場中我國在印度洋作業之大目流綱及鮪延繩釣漁船返港所卸之長鰭鮪；此外，水試所海功號試驗船1990年11月～1991年1月於印度洋作業所得之長鰭鮪亦併入分析。比較大目流網及鮪延繩釣所漁獲之長鰭鮪體長組成、生殖腺指數分布，顯示鮪延繩釣所捕獲長鰭鮪之體型均較大目流綱所漁獲者為大，且成熟。另外，由長鰭鮪之卵徑組成分布中得知大型卵粒數會遀著生殖腺指數的增大而增加；因此，生殖腺指數可作為判別成熟度之指標。本魚種之最小生物年齡與體長分別為5.58歲和83.28～90 cm。長鰭鮪之孕卵數和尾叉長並無明顯相關關係，尾叉長101 cm到113 cm間之長鰭鮪其孕卵數約在180萬粒至275萬粒間；而其相對孕卵數（卵數／g體重）約在80卵粒到122卵粒間。卵巢之成熟初期是由於卵巢中卵數的增加和卵徑之增大所致；惟當卵巢重達400 g後則以成熟卵數之增加為主。由成熟卵巢之卵徑分布所呈現的顯著變動，可推斷本魚種屬多次產卵型。大目流網、鮪延繩釣所漁獲長鰭鮪之性比分別為0.69、0.66，皆顯示雌魚數較雄魚數多；而各尾叉長別之性比亦有此種現象。

關鍵字

沖鲹 ； 鱗片 ； 年齡 ； 成長參數 ； 臺灣

並列摘要

Studies concerning maturity and fecundity of Indian albacore in thispaper were mainly based on samples collected from Taiwanese gillnetters andlongliners operating in the Indian Ocean from October 1987 to March 1990,andspecimens caught by R/V Haikung of the Taiwan Fisheries Research Institutefrom November 1990 to January 1991.Longliner caught larger and more mature albacore than gillnetter.Frequencydistributions of ova diameter showed that the GSI could be used as an index ofmaturity for the fish.Biological minimum age and size of this fish are estimatedat 5.58 years and 83.28-90.00 cm,respectively.No statistical relationship betweenfecundity and fish length was observed.The absolute and relative fecundityfor albacore 101 cm to 113 cm ranged 1.8-2.75 million and 80-122/g body weight.The maturation process of ovary is assumed,firstly,to be the increase of bothegg number and ova diameter and then,when the maturation proceeds to acertain level,only the increase of egg number exclusively.Significant variationsof ova diameter in the maturing ovaries suggested the fish is a multiple spawner.Many females were found in both gillnetter and longliner.The sex ratios were0.69 and 0.66,respectively.Females outnumbered males for different fork lengthgroups and in spawning season.

並列關鍵字

White-Tongued Crevalle ； Uraspis Helvolus,Scale,Age,Growth Parameters ； Taiwan