THE QUANTITY DISTRIBUTION OF GIANT JELLYFISH AND ITS RELATIONSHIP TO SEAWATER TEMPERATURE AND SALINITY IN INSHORE WATERS OF THE NORTHERN LIAODONG BAY REGION
辽东湾北部近海大型水母数量分布和温度盐度特征

The distribution of giant jellyfish and the ecological type were analyzed on the basis of the sampling data obtained during the surveys in inshore waters within 10m isobath of the northern Liaodong Bay, Bohai Sea from late May to late July from 2009 to 2011. There were four main species of giant jellyfish, Rhopilema esculentum, Nemopilema nomurai, Cyanea nozakii and Aurelia sp.1. The larval medusae of R. esculentum was mainly found within 5m isobath in coastal estuaries of the northern Liaodong Bay, and adult medusae was mainly found in both sides of the waters near 5m isobath. The adult had a slightly tendency to go to deep waters or low jellyfish catch density waters with the individual increasing. The relatively high temperature and low salinity area of coastal estuaries was an optimum environment for the growth of R. esculentum. There were a large amount of larval medusae of N. nomurai in inshore waters of northern Liaodong Bay in June, and the amount of N. nomurai decreased a lot with the individual increasing in the area in July. Aurelia sp.1 mainly inhabitated in the southern Liaodong Bay, and was found a few in inshore waters of the northern Liaodong Bay in 2010 and 2011. C. nozakii inhabitated in high salinity area, and was few found in Liaodong Bay in recent years. Among giant jellyfishes in Liaodong Bay, N. nomurai grew more quickly. The occurrence time of the larval medusa of R. esculentum and N. nomurai in Liaodong Bay was later than in the Yellow Sea and East China Sea.