南澎列岛近海海域底拖网鱼类组成的季节性变化

Studies on seasonal changes of species components of fishes caught by bottom trawl in coastal waters of Nanpeng Islands

1991年逐月对南澎列岛近海海域作底拖网调查 ,共捕获鱼类 1 32种 ,其中软骨鱼类 7种 (4目 6科 6属 ) ,硬骨鱼类 1 2 5种 (1 0目 5 8科 95属 ) ,后者以鲈形目居多 (6 9种 )。全年渔获优势种类为条尾鲱鲤、黑天竺鱼、二长棘鲷、大头狗母鱼、多齿蛇鲻、三线矶鲈、绿布氏筋鱼、多鳞鱼喜和乔氏台雅鱼等 9种 ,其渔获尾数分别占全年渔获总数 3%以上 ,出现的月份数皆不小于 8,渔获尾数之和是渔获总数的71 .1 %。季节性优势种类除全年优势种类外 ,尚有粗纹 、半线天竺鲷、印度白姑鱼、静 和翼红娘鱼等 5种 ;各种类全年渔获尾数及出现月份数相关 ,各月份的渔获尾数和渔获种数不相关 ;渔获物中仅有少量的中上层鱼类 (1 3种 )。就适温性而言 ,该海区鱼类以亚热带性为主并兼有热带性特征 ,以Shannon、Brillouin、Simpson和McIn tosh等多样性指标及相应的Hurlbert均匀度指标对逐月样本作估计 ,这 8种指标之间高度显著相关 ;该海域鱼类的Shannon多样性指标及相应的均匀度指标皆以秋冬季为高 ,春夏季较低。

From the monthly surveys of bottom trawl fishing in 1991, 132 fish species have been identified in coastal waters of Nanpeng Islands, which are composed of 7 Chondrichthian species (4 orders, 6 families and 6 genera) and 125 Osteichthian ones (10 orders, 58 families and 95 genera). The perciform fishes (69 species) are the most abundant among Osteichthyes. The annual dominants are 9 species: fin striped goatfish Upeneus bensasi , black cardinalfish Apogonichthys niger , crimson tai Parargyrops edita , bluntnose lizardfish Trachinocephalus myops , great lizardfish Saurida tumbil , striped pigfish Parapristipoma trilineatum , Bleeker's sand lance Bleekeria anguilliviridis , common asohos Sillago sihama and Jordan's damselfish Daya jordani . Each of them amounted to more than 3% of the annual catch in number, and occurred in the sampling areas for no less than 8 months. They formed 71.3% of the total fish number. The seasonal dominants, besides the annual ones, are 5 species: lined ponyfish Leiognathus lineolatus , bottom perch Apogon semilineatus , white croaker Argyrosomus indicus , pugnose ponyfish Leiognathus insidiator and forknout searobin Lepidotrigla alata . The annual catch in number is related to the month number of occurrence, whereas the monthly catch in number is not correlated with species number. The specimens include few pelagic species (13 species). According to thermophily, the fishes in the areas consist principally of the subtropical species, concurrently of the tropic ones. The diversity and the evenness in samples collected month by month are estimated by Shannon, Brillouin, Simpson, McIntosh diversity indices and the corresponding Hurlbert evenness indices. The 8 indices are very significantly correlated. The indices of Shannon diversity and the corresponding evenness in autumn and winter are higher than those in spring and summer for the fishes caught in the areas.