The composition of fish community in south Haizhou Bay based on the trawling survey

Abstract:

According to the four cruises of fisheries survey conducted in south Haizhou bay, eastward of Lianyungang in Jiangsu Province, all the catch fish species from bottom trawl of 24 stations were identified to species level, and the spatial and temporal distributions of species composition were analyzed. The results showed that 98 species were collected from the south Haizhou bay, involving 2 class, 15 orders, 47 families and 77 genera. Most of the fish species belong to Perciforme, Scorpaeniforme, Pleuronectiformes and Clupeiforme. More than 50% of the total species belong to Perciforme in different seasons except for winter, different stations also showed different patterns in species composition, although difference was not tested in statistical analysis; the dominant species were less than four species in every season, pelagic species dominated in spring and winter, and commercial species were commonly dominated in summer and autumn. The highest weight density occurred in spring, then summer and autumn, winter is the lowest; however, the highest individual density occurred in winter, followed by spring and summer, and autumn was the lowest. The density differences between near-shore and off-shore were also revealed in this study without any statistical difference. Margalef diversity index was analyzed with highest value in spring, followed by summer and autumn, winter had a relatively low species composition. The value of indices showed different patterns in different stations without significant difference. The protection of fisheries resources in Haizhou bay has been kept at a stable level. Closed fishing system should be maintained and the minimum net size should also limited. Sustainably developing some novel fisheries should be considered to better utilize the marine resources.