渔业科学进展2012，Vol.33Issue(4)：1-10,10.
南极半岛邻近水域南极大磷虾商业捕捞群体的年龄结构时空变化
Temporal and spatial variations in age structure of Antarctic krill Euphausia superba (Dana) from commercial fishery in the waters near the Antarctic Peninsular
摘要
Abstract
During 2009/2010 and 2010/2011 fishing seasons, Antarctic krill Euphausia superba Dana from the south Atlantic Ocean was harvested by Chinese commercial fishery vessels in the CCAMLR subarea 48. 1 near the South Shetland Islands and CCAMLR subarea 48. 2 near the South Orkney Islands, respectively. The length-frequency and sex ratio of krill collected in both fishing seasons were analyzed to estimate its growth, age structure, and evaluate potential temporal-spatial variations of its spawning season. Based on the results of length-frequency fitting mixture distribution, five age groups (l+~5+) were observed in the krill population. The age structure and sex ratio of krill varied in the two fishing seasons and subareas. In the waters near the South Shetland Islands of subarea 48. 1, E. superba population was domi-nanted by individuals at age 5+ in January, 2010 and December, 2011. In the two months, gravid female were abundant and consisted over 40 percent of all krill numbers. Gravid females were between age 3+ ~5+ and dominated by those of age 5+. In contrast, in the waters near the South Orkney Islands of the subarea 48. 2, E. superba population was still dominated by individuals of age 5+in February, 2010, yet subsequently by those of age 3+in February, March and April, 2011. Although gravid females of age 5+ were observed, their proportions decreased only about 15% in February, 2010 and less than 1% from February to April, 2011. Monthly observation during February, March and April, 2011 showed that it tended to be fewer gravid individuals, more unimodal age structure and increased sex ratio. In addition, the krill growth rate decreased with month and was negative value in March and April. Based on the above results, it could be inferred that in subarea 48. 2,E. superba spawning peak in 2010/2011 fishing season should be earlier than February,2011, while spawning remained in that month of 2009/ 2010 fishing season.关键词
南极大磷虾/年龄组成/体长频数/混合分布分析/性比Key words
Euphausia superba Dana/Age structure/Length-frequency Fitting mixture distribution/Sex ratio分类
农业科技引用本文复制引用
左涛,徐鹏翔,李灵智,陈丹,赵宪勇,黄洪亮,夏辉,徐玉成,孙坚强,冯春雷,王新良,朱国平..南极半岛邻近水域南极大磷虾商业捕捞群体的年龄结构时空变化[J].渔业科学进展,2012,33(4):1-10,10.基金项目
公益性行业(农业)科研专项(201203018)、农业部“南极海洋生物资源开发利用”和山东省泰山学者“海洋渔业资源与生态”岗项目共同资助 （农业）
