深延縄の漁獲結果からみたメバチの遊泳層について

概要

論文の詳細を見る
The author has studies on the results of measured soaking depth and the fishing operations of the deep tuna longline (having 10 branch lines) in the tropical area of eastern Indian Ocean, and has obtained the following results. 1. The range of measured soaking depth of the deep tuna longline is from 98 m to 299 m. 2. The catch rate of bigeye tuna of deep hooks is high compared with shallow hooks. This result would show that the density of destribution is considerably high at the deepest hook. 3. In the case of bigeye tunas caught by the deep tuna longline, the hooking time of deep hooks is earier than shallow hooks. 4. The density of destribution of bigeye tuna is thick in the daytime but the center of destribution gradually begins to rise to the shallow layer before and after sunset, and the inclination of distribution nearly disappears in the midnight. 5. The deep tuna longline about bigeye tunas has a better fishing effect than the regular tunna longline (having 5 branch lines).
三重大学水産学部の論文
1982-10-01