台灣花腹鯖的年齡與成長

Abstract

1．本省鯖魚業漁獲組成單純，漁獲量又?近海漁業之冠，主要是以一支釣及巾著網?漁具，漁獲物多?叉長28?32公分之成魚。少數體型小者是以地曳網捕得。 2．主要年齡組成?1+。在2?4月時則有一群2+的魚加入。平均體長在2?4月時亦可明顯地分成兩個不同的群。 3．南方澳區，年初仔魚到年底時平均體長約?27.5公分，到次年末可達32公分。 4．魚釣島區，年初仔魚到年底時平均體長約?27公分到次年末可達30公分。 5．南方澳區的魚與魚釣島區的魚成長情形大致相同，無顯著差異。 6．高雄區的魚成長較南方澳區及魚釣島區的魚要快。

1. Catch of the mackerel fishery composed of almost only spotted mackerel, Scomber tapeinocephalus BLEEKER, stands highest in the Taiwan inshore fisheries. Most of the spotted mackerels with fork length of 28-32 cm were caught by handlines and purse seines. 2. The principle age-class in the catch is 1+. Between February and April, there came the 2+ age-class. The average fork length could be seperated into 2 groups from Feburary to April. 3. The new-born grows to 27.5 cm at the end of the first year and 32 cm at the end of second year in Nanfangao. 4. The new born grows to 27 cm at the end of the first year and 30 cm at the end of second year in Fishing Island. 5. There is no significant difference between the growth of fish from Nanfangao and Fishing Island. 6. The fish from Kaohsiung grows much faster than that from Nanfangao or Fishing Island.