臺灣近海鮪延繩釣漁業1981～82漁場、漁季、漁況及主要魚種—黃鰭鮪的生物學研究

The Inshore Tuna Longline Fishery of Taiwan Fishing Grounds, Fishing Seasons, Fishing Conditions and a Biological Study of the Major Species, Yellowfin Tuna, 981-82

孫志陸(Chi-Lu Sun) ； 楊榮宗(Rong-Tszong Yang)

《臺灣水產學會刊》 10卷2期 (1983/12) Pp. 11-41

https://doi.org/10.29822/JFST.198312.0002

摘要

續前年計劃，自70年7月起至71年6月止，以束港所屬近海鮪釣船為對象，調查其在西太平洋作業實況，並在束港魚市場對黃鰭鮪進行包括體長組成、性比及成熟度等生物調查研究，結果顯示：
1.近海鮪釣作業漁場仍在23°N以南，赤道以北，145°E以西的海域。
2．黃鰭鮪仍為主要漁獲對象。以漁獲物尾數組成來看，黃鰭鮪佔51~72%，以重量組成來看，黃鰭鮪佔65~81%。
3. 4月至6月在呂宋島東方、巴士海峽束方到臺灣東方海域漁獲的黑鮪是屬於成熟的中大型魚。
4．各區全年體長在118cm 至 153cm間的黃鰭鮪，隨著體長之增加，雌魚的尾數隨之減少，體長在136cm 至159cm 間雄魚數遠多於雌魚數。各海域全年總雌雄比大致相同，大約接近l:2。
5．在10°N至23°N , 110°E 至135°E間水域的雌性黃鰭鮪，其成熟季節似乎在春夏季。各區雌魚在106cm至124cm 以上開始有成熟魚出現。
6．我國近海鮪釣船，若能將目前作業漁船向南及向東擴展，而集中在10°N至10°S, 140°E至170°E之間海域作業，將會有更佳的漁獲。

並列摘要

From July 1981 to June 1982 investigations were made on the seasonal changes of the fishing grounds and the catch composition of the Taiwanese Inshore Tuna Longline Fishery in the western Pacific Ocean. Biological informations, including length composition, sex ratio, and sexual maturity were also studied for the major species, yellowfin tuna, at the Tung-Kang Fish Market. The results obtained reveal that:
1. Fishing operations are still limited to the waters south of 23°N, north of the equator, and west of 145°F, to include the South China Sea.
2. A catch composition analysis showed that the major species of catch remains yellowfin tuna which occupied, 51-72% of the total catch in numbers and 65-81% in weight.
3. The bluefin caught by the Inshore Tuna Longline Fishery east of the Philippine Islands, Bashi Channel, and Taiwan during April through June were medium or large mature fish.
4. From lengths of 118cm through 153cm, the percentage of females gradually decreased as the specimens increased in size. At a length of about 136-159cm,. the proportion of males greatly exceeded that of females. The total sex ratio of the combined length classes in each fishing ground was close to 32% of females.
5. The spawning peaks for female yellowfin seem to occur in the second and third quarters in the waters from 10°N to 23°N and 110°E to 135°F. Female yellowfins attained maturity at or exceeding 106-124cm depending on the fishing grounds.