서대 3중자망의 망목 선택성에 관한 연구

A study on the selectivity of the mesh size in trammel net for Cynoglossidae spp.

  • 발행 : 2000.05.01

초록

서대 3중자망의 망목 선택성을 규명하기 위하여 각각 3가지 종류의 망목(70.5mm, 86.6mm, 101mm)으로 구성 된 자망 및 3중자망을 사용하여 1999년 5월부터 8월까지 전남 여수시 돌산도 연안에서 총 30회의 실험조업을 하고, 그 결과를 분석하였다. 망목 선택성 곡선은 개서대를 대상으로 Kitahara 방법으로 작성되었다. 본 연구에 대한 결과를 요약하면 다음과 같다. 1. 현용어구 규격인 3중자망(내망 망목 70.5mm망)의 어획비율은 39.0%로, 자망 15.8%에 비해서 약 2.5배 높았다. 2. 3중자망의 선택률이 1이 되는 최적 l/m값은 3.51로 자망 3.38에 비해서 약 0.13 높게 나타났다. 3. 3중자망의 낮은 체장계급에서의 선택성은 자망과 비슷하였으나, 높은 체장계급에서의 선택성은 자망에 비해서 떨어졌다. 이 때 3중자 망의 50% 선택 구간은 1.33으로 자망 0.83에 비해 1.5배 넓게 나타났다. 이상의 결과에서 볼 때, 서대의 경우 3중자망은 자망에 비해 어획성능이 우수하고, 망목 크기를 조절함으로서 대상 어종의 어획 체장을 제어할 수 있음을 알 수 있었다.

Test fishing was carried out to examine the selectivity of the mesh size in trammel net for tonguefish (Cynoglossidae spp.) from May to August, 1999 and a total of 30 times of test fishing have been done in the coastal waters around Dolsando, Yosu, South Chunra province, Korea. A gill net and a trammel net which were composed of three different mesh sizes (70.5mm, 86.6mm and 101mm) were used for the experiment. The selectivity curve of mesh size was estimated by Kitahara's method for Robust tonguefish (Cynoglossus robustus). The results obtained are summarized as follows ; 1. Catching efficiency of the trammel net (70.5mm-sized-lint main net) was 39.0% and it was 2.5 times higher than 15.8% for the gill net. 2. The optimum l/m value of the trammel net was 3.51 and it was 0.13 higher than 3.38 for the gill net. 3. The selectivity of trammel net was similar to that of the gill net for low length-class. However, the selectivity of trammel net was not good compared with that of the gill net for high length-class. The 50% selectivity was 1.33 for the trammel net and 0.83 for the gill net. According to the experimental results, fishing efficiency of the trammel net was better than that of the gill net for tonguefish (Cynoglossidae spp.) and it was known that catch length for targeted species could be selected by controlling the mesh size.

키워드

참고문헌

  1. FAO Fisheries Technical Paper v.306 no.1 Intoduction to tropical fish stock assessment (Part 1-Manual) FAO
  2. Fisheries Research v.26 Selectivity and gear dfficiency of trammel nets for kuruma prawn (Penaeus japonicus) Fujimori, Y.;Tokai, T.;Hiyama, S.;Mauda, K.
  3. Bull. Hokkaido Reg. Fish. Res. Lab. v.25 On the Gill net Mesh Selectivity IShida, T.
  4. Bulletin of the Japanese Society of Scientific Fisheries v.34 no.9 Mesh selectivity curve of sweeping trammel net for branqullos Kitahara, T.
  5. Nippin Suisan Gakkaishi v.54 no.2 Catching efficency of trammel net with different slacknesses and mesh sizes of inner net Koike, A.;Matuda, K.
  6. Bulletin of the Japanese Society of Scientific Fisheries v.57 no.7 A tank experiment on selectivity components of a trammel net for Tilapia mossambica Tatsura, M.
  7. 現代韓國漁具圖鑑 國立水産振興院
  8. 最適化法 近藤次郎
  9. 沿近海漁業槪論 李秉錡;朴丞源;金鎭乾
  10. 水産學シリ-ズ v.28 漁具の漁獲選擇性 日本水産學會(編)