桁拖网渔具分隔网片对蟹类的分隔效果  

Efficiency of separator panels in beam trawls for crabs

作　　者：张健[1,2] 白伦[1,2] 

机构地区：[1]大洋渔业资源可持续开发省部共建教育部重点实验室,上海海洋大学,上海201306 [2]农业部大洋渔业资源环境科学观测实验站,上海海洋大学,上海201306

出　　处：《海洋渔业》2013年第2期217-223,共7页Marine Fisheries

基　　金：公益性行业(农业)科研专项(201203018);国家自然科学基金(NSFC31001138);上海市教委创新项目(11YZ156)

摘　　要：传统捕虾桁拖网渔具网目小、渔获对象繁杂、选择性能差。使用网片式分隔装置、实现渔具的选择性捕捞是缓解这一问题的有效手段之一。2005年秋汛期间,在吕四渔场桁拖网渔业中开展了网目尺寸分别为60、75和90 mm分隔网片的海上生产试验,本文通过蟹类渔获为研究对象,分析分隔网片对其的分隔效果。试验结果显示,使用以个体接触分隔网片概率和网片对个体的留存率为基础的分隔效率模型,对蟹类甲宽分布数据的拟合发现,随着网目尺寸的增大,分隔网片对三疣梭子蟹(Portunus trituberculatus)、细点圆趾蟹(Ovalipes punctatus)的50%留存甲宽和留存率范围均有所增大;而上述2种蟹类个体接触不同网目尺寸分隔网片的概率则没有明显的一致性变化趋势。试验结果表明,蟹类在到达桁拖网网身部时具有一定的游泳能力且具有一定的游泳高度,也反映出使用向下倾斜的分隔网片在结构和装配上是比较合理的。The poor size selectivity of traditional shrimp beam trawl fishenes m me offsnore o me Sea, to some extent, is due to the small mesh size codends and diverse target species. Utilization of separator panels to achieve selecitve fishing is one of potential solutions. In the fall of 2005, experiments on inclined separator panels of different mesh sizes （60ram, 75mm and 90mm ） were carried out in the Lvsi Fishing Ground. In this paper, a model for separating efficiency based on the encountering probability of crab individuals and retention probability of panels was fitted to the carapace width frequency of the crabs catch. The results of model fittness demonstrated that the 50% retention carapace width and the retention range of carapse width of swimming crab, Portunus trituberculatus and sand-looking crab, Ovalipes punctatus increased with the increase of the mesh sizes of separator panels. Probability curves of contacting different separatorpanels were not significantly different for any crab species, which implied that crab individuals had considerable swimming ability and swimming height when they reached the trawl body, and the design and rigging of the inclined separator panels were reasonable.

关 键 词：桁拖网 分隔网片 三疣梭子蟹 细点圆趾蟹 分隔效率 

分 类 号：S972.13[农业科学—捕捞与储运]