南沙群岛中北部重要岛礁鱼类资源调查

Survey for coral reef fish resources in the center & north waters of the Nansha Islands

1998年4月和1999年5月,采用手钓、延绳钓和流刺网作业在南沙群岛的渚碧、南薰、东门、美济、赤瓜、永署和华阳等7座珊瑚礁水域进行了2个航次的鱼类资源调查。累计投入的捕捞努力量分别为手钓357钩·时、延绳钓4220钩、流刺网19750m,单次作业努力量手钓6～18钩·时、延绳钓40～480钩、流刺网40～2400m。捕获鱼类180种,渔获量1860尾1540.4kg,其中手钓102种1225尾196.8kg,延绳钓36种82尾1234.7kg,流刺网70种553尾108.9kg。按岛礁平均,渔获率和单位捕捞努力量渔获量(CPUE)手钓为351.1尾·(100钩·时)-1、51.9kg(100钩·时)-1,延绳钓为2.6尾·(100钩)-1、39.0kg·(100钩)-1,流刺网为51.4尾·(1000m)-1、7.5kg·(1000m)-1。礁坪区流刺网的渔获率和CPUE为170.3尾·(1000m)-1、23.1kg·(1000m)-1,均高于礁缘浅水区和礁缘深海区。捕获的主要经济种类有鲨鱼、裸胸鳝、石斑鱼、笛鲷、裸颊鲷、鹦嘴鱼和隆头鱼科鱼类等。华阳和永暑礁鱼类资源比较丰富,具有较高的开发潜力;东门、美济和南薰礁次之,也有一定的生产价值;赤瓜和渚碧礁基本没有开发价值。

In April 1998 and May 1999, two survey cruises were carried out in seven coral reef waters of the Nansha Islands-Zhubi, Nanxun, Dongmen, Meiji, Chigua, Yongshu and Huayang reef by handlining, longlining and gillnetting. For total fishing efforts input in the survey, handlining was 357 hook·h, longlining 4 220 hooks, and gillnetting 1 9750m. For fishing efforts per operation, handlining was 6-18 hook·h, longlining 40-480 hooks, and gillnetting 40-2 400m. A total of 180 species were caught and their catch was 1 860 ind 1 540.4kg, among which, handlining caught 102 species 1 225 ind 196.8kg, longlining 36 species 82 ind 1234.7 kg, and gillnetting 70 species 553 ind 108.9kg. For mean catch rates and CPUEs per reef, handlining was 351.0 ind·(100 hook·h)^(-1) and 51.9kg·(100 hook·h)^(-1), longlining 2.6 ind·(100 hooks)^(-1) and 39.0kg·(100 hooks)^(-1), and gillnetting 51.4 ind·(1000m)^(-1) and 7.5kg·(1000m)^(-1). Both catch rate and CPUE of gillnetting in reef flat were higher than shallows and depths of reef margin, with 170.3 ind·(1000m)^(-1) and 23.1kg·(1000m)^(-1). Major commercial species caught included sharks, morays, groupers, snappers, pigface breams, parrotind and wrasseses et al. Huayang and Yongshu reef are abundant in reef fish resources and have higher exploitation potential. Dongmen, Meiji and Nanxun reef are lower than Huayang and Yongshu reef in usable abundance of reef ind, but also have production value. Chigua and Zhubi reef basically have no fishing value.