학술논문

Estimation of the fishing efficiency of a mid-water trawl for Pacific saury Cololabis saira using a high-frequency side-scan sonar / サイドスキャンソナーを用いた中層トロールのサンマに対する採集効率の推定
Document Type
Journal Article
Source
日本水産学会誌 / NIPPON SUISAN GAKKAISHI. 2010, 76(4):658
Subject
サイドスキャンソナー
サンマ太平洋北西部系群
中層トロール
分布密度
採集効率
画像解析
Language
Japanese
ISSN
0021-5392
1349-998X
Abstract
In order to improve the accuracy of abundance estimations of Pacific saury Cololabis saira, it is important to raise the fishing efficiency precision of a mid-water trawl (type NST-99, the sampling gear used for stock assessment) for saury. Using a 500 kHz side-scan sonar (SSS), we ensonified surface waters and measured the fish number using image processing methods. Simultaneously, we tried to catch saury in the same waters with the mid-water trawl. We estimated the fishing efficiency of the mid-water trawl as 0.179 (current value used is 0.144) by comparing the number of saury caught by the trawl net per swept-area with the number of saury per swath-area estimated from analysis of SSS records.