Application of Gordon-Schaefer Model to evaluate bioeconomic and management aspects of Scomberomorus sinensis fishery in Shandong, China

Abstract

Commercial marine fishery resources of China are generally considered to be overexploited. This condition may lead to the extinction of fishery resources and overcapitalization of the fishing fleets. Therefore, this study simultaneously evaluates the stock status and economic efficiency of a very important commercial marine fishery resource, i.e., <em>Scomberomorus sinensis</em> of Shandong, China by using a data for a period between 2003 and 2016. It employs a famous fishery surplus production model, <em>viz</em>., Gordon-Schaefer Model (GS-model) to compute various harvest levels and their corresponding effort levels. These levels or reference points (RPs) were estimated for three exploitation states, i.e., maximum sustainable yield (MSY), maximum economic yield (MEY), and open access yield (OAE). At MSY the harvest, effort, and revenue were calculated as H_MSY = 185357 metric tons (MT), E_MSY= 35624 and 1.80 billion RMB. On the other hand, the same parameters computed at MEY remained H_MEY = 137177 MT, E_MEY = 17462 and 5.01 billion RMB, in that order. Harvest and corresponding effort levels at OAE were computed as H_OAY = 185285 MT and 34924, respectively. It is also found that despite controlling the effort levels, CPUE is showing a decreasing trend in the past few years which may be an outcome of overexploitation. Moreover, the revenue generated at MEY is about three times greater than the revenue generated at MSY. This increased revenue can be achieved by further lowering the effort levels. Thus, there is a dire need to make and implement such policies which can conserve <em>S. sinensis</em> fishery resource and increase the revenue at the same time. Therefore, further comprehensive studies are needed in this regard as this study is just a preliminary work.