北上期におけるマイワシの三陸まき網漁場に関する知見

概要

論文の詳細を見る
Very little research has been done on the mechanism for forming fishing grounds, particularly on the route by which Japanese sardine Sardinops melanostictus migrate to the Sanriku coast during their northward migration. In this connection, data on the fishing ground were analyzed and its relationship with a warm streamer was investigated using data recorded by fishing boats, satellite aided SST distribution charts etc. in the period from 1987 to 1990. As a result, the following were found: (1) Sardine schools during northward migraiton do not come to the area off the Sanriku coast sequentially from off the Boso/Jyoban coast, but tend to come in random waves. (2) From the direction of motion of the schools approximately heading north-northeast, they are considered to move further north during their feeding migration. (3) The suitable SST for a catch (Ts) is 11.0°C on average with a standard deviation of 2.2°C, and 85% of SSTs of warm streamers are included in the range of Ts. (4) The centre of gravity of fishing grounds and the warm streamer have a close correlation with their latitude (coefficient of correlation is 0.85). As a whole, sardine schools in the early fishing season off the Sanriku coast are fed from the warm streamer during their feeding migration, where the warm streamer is considered to serve as a migration route.
公益社団法人日本水産学会の論文