2014年11月在海州湾前三岛人工鱼礁区使用手钓渔具进行钓捕实验,分析不同全长许氏平鮋(Sebastes schlegeli)的分布及其YPUE(单位捕捞努力量渔获质量)与近礁距离(手钓放钩点与距其最近投礁点之间的水平距离)的关系,研究许氏平鮋在鱼礁区的分布情况。手钓渔获物中许氏平鮋的尾数占总钓捕渔获物尾数的82.58%。应用SPSS软件,分别对许氏平鮋的鱼体全长和YPUE与近礁距离的关系进行初步分析。文中采用了2种YPUE的定义方式:以单位时间内每人钓获许氏平鮋的质量定义的YPUE1与近礁距离x的关系为YPUE1=681.474-108.886ln x,其Pearson相关系数为-0.730;以每人每次放钩钓获许氏平鮋的质量定义的YPUE2与近礁距离x的关系为:YPUE2=186.597+17 374.787/x,其Pearson相关系数为-0.692。这2种定义方式中,第1种定义方式的方程与回归曲线的拟合度更高。研究结果表明:体型越大的许氏平鮋在近礁距离越小的区域出现的数量越多,而由YPUE所反映的鱼群密度随着近礁距离的增大而减小。

Sebastes schlegeli is one of the main commercial fish species of the artificial reefs in Qiansan Island of Haizhou Bay.In this study,hook-and-line fishing gears were used to collect fishes,which were similar to those used in the local recreational fisheries.The longitude and latitude of sampling sites and artificial reef sites were recorded,and the horizontal distance from sampling site to its nearest artificial reef site(distance off reef)was figured out.Catches included Sebastes schlegeli,Hexagrammos otakii,Sebastiscus marmoratus and Chelidonichthys spinosus,of which the individuals of Sebastes schlegeli accounted for 82.58%.SPSS 19.0was used to analyze the relationships between the total length,the yield per unit effort(YPUE)of Sebastes schlegeli and the distance off reef.Significant difference was observed between total length,YPUEand the distance off reef.The results showed that the larger the fish was,the more probably it emerged in the areas near the artificial reef site.The difference in movements related to the total length may be attributed to foraging behaviors.Larger fish may realize a greater forging success using a sedentary ambush strategy.As a contrast,smaller fish may be more likely to actively pursue appropriate prey which seemed to be less abundant in the areas near artificial reef site.This could explain why they tended to have higher movement probabilities than larger fish.YPUEdeclined with the increase of the distance off reef,which meant the density of reef fishes decreased as the sampling site set farther away from the artificial reef.Two types of YPUE were standardized in this study.YPUE1 stood for the yield of fishes hooked by every angler per minute,while YPUE2 stood for the yield of fishes hooked by every angler per drop.The equation between YPUE1 and x representing the distance off the reef is YPUE1=681.474-108.886(lnx).The equation between YPUE2 and xis YPUE2=186.597+17374.787/x.Both YPUE1 and YPUE2have a significant negative correlation with the distance off reef,while YPUE1 seemed to have a more significant correlation than YPUE2(-0.730vs-0.692).This may be owed to the frequency of drops in every sampling site,which was twice at most.The results on the distribution of reef fishes in this study may be a reference for commercial fishing.The more fish appeared in the areas around the reef site,the more catches there would be.Hook-and-line fishing gears were not widely used in the marine investigation and experiments in China so far.However,the research design of this study may accelerate the development of recreational fishery in which fishing with hook-and-line gears was one of the most important entertainment forms.Meanwhile,the research also reflected that the artificial reefs did well in fish-gathering effect,which may aid to making further progress in the similar study.