舟山渔场及邻近海域蟹类种类组成和时空分布

根据2006年8月、2007年1月、5月和11月4个季节在舟山渔场及邻近海域(29°30′N—32°00′N,127°E以西)开展海洋生态系统综合调查时所获得的蟹类调查资料,以渔获率作为蟹类数量指标分析该海域蟹类资源状况,包括种类组成、数量分布和时空变化。结果表明,本次舟山渔场及邻近海域调查共得蟹类种类43种,隶属于10科、21属。优势种类为细点圆趾蟹、双斑蟳、三疣梭子蟹、日本蟳、红星梭子蟹、红线黎明蟹,以上6种蟹类占蟹类总渔获量的94.58%。本次调查与20世纪90年代末在东海大陆架海域的蟹类资源调查结果相比,蟹类种类组成和优势种变化不大。从蟹类渔获率来看,秋季以舟山渔场最高,夏季以江外渔场最高,蟹类资源密集区主要位于长江口渔场和舟山渔场北部。

SPECIES COMPOSITION AND SPATIO-TEMPORAL DISTRIBUTION OF CRABS IN ZHOUSHAN FISHING GROUND AND ITS ADJACENT AREAS

Based on data from the comprehensive investigation of marine ecosystem in August, 2006 and January, May, and November 2007, we use catch rate as the index for quantitative distribution of crabs, and analyze the changes of species composition and quantitative distribution of crabs in 29°30′—32°00′N, west of 127°00′E in the Zhoushan fishing ground and adjacent waters. Results show that there are 43 species of crabs being identified in the survey area, belonging to 10 families and 21 genera. The main dominants, Ovalipes punctatus, Charybdis bimaculata, Portunus trituberculatus, Charybdis japonica, Portunus sanguinolentus, Matuta planipes, however, account for 94.58% of the total catch. Compared to the results of the crab resource survey in the East China Sea in 1990s, the species composition and dominant species have not changed. In autumn, Zhoushan fishing ground has the highest CPUE, and in summer, it’s in the Jiangwai fishing ground. The highest catch of crabs is in the north of Zhoushan fishing ground and the Yangtze estuary fishing ground.