Analysis on variation distribution of center fishing ground for light falling-net in offshore of the South China Sea: based on statistics of fishery surveillance to Guangxi fishing vessels

Guangxi fishing vessels with light falling-net are one of the fishery powers in offshore of the South China Sea. Based on the data of Guangxi fishing vessels inthatareafrom February to May, 2013 recordedby Guangxi vessel monitoring system, we calculated the ratios of fishing effort in each single sea region to the total fishing effort in offshore, which were regarded as indicators for intensity of fishing activities. The sea regions were categoried into four types: high intensive, intensive, low intensive and extensive. Results show that the fishing efforts from high intensive and intensive regions where were concluded as the center fishing grounds in offshore of the South China Sea, accounted to more than 2/3 of the total fishing effort. The center fishing ground covered 27 sea regions distributed mainly in northern part of Nansha (Spratly) and focused around Taipin Island. Besides, we analyzed the variationin distribution of center fishing ground for light falling-net, discussed the present status and problems confronted by fisheries development in offshore of the South China Sea, and provided countermeasures and advices for fishery development and management in that area.