Size-dependent mortality of red sea bream, Pagrus major, juveniles released with fluorescent otolith-tags in News Bay, Japan
Size-dependent mortality of red sea bream, Pagrus major, juveniles released with fluorescent otolith-tags in News Bay, Japan
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DOI：
10.1111/j.1095-8649.1989.tb03046.x
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发表时间：
2006-01
影响因子：
2
通讯作者：
K. Tsukamoto;H. Kuwada;J. Hirokawa;M. Oya;S. Sekiya;H. Fujimoto;K. Imaizuml
中科院分区：
文献类型：
--
作者：
K. Tsukamoto;H. Kuwada;J. Hirokawa;M. Oya;S. Sekiya;H. Fujimoto;K. Imaizuml
分别以2.67 × 105和7.56 × 105条幼鱼为实验材料，对三种规格（10、20和40 mm t.l.）1987年7月和1988年6月，在日本大分县的新闻湾，分别释放了耳石中标记有荧光物质的100只，目的是估计不同发育阶段的生长和死亡率。在1987年和1988年释放的鱼中，分别有10618和4413条在这两年被重新捕获。释放的鱼留在海湾，直到夏末，后来迁移到开放的沃茨。1987年释放的40毫米组的鱼长到200毫米t.l.以上。在一年释放后19天的平均生长率在40 mm组（0.87 mm天-1）中高于20 mm组（0.74 mm天-1）。1987年，40 mm和20 mm鱼19天以上的存活率分别为59.0%和10.1%，1988年，40 mm、20 mm和10 mm鱼30天以上的存活率分别为69.2%、3.3%和0.0%。同类相食的存在下，显着的耳石20毫米的鱼在几个40毫米的个人的胃夺回释放后2天。尺寸依赖性的增长和尺寸选择性死亡率都注意到在少年红鲷，即较大和较小的个体之间的相对大小差异保持在标记和重新捕获之间的时期，死亡率与大小成反比。
Totals of 2.67 x 105 and 7.56 x 105 juvenile red sea bream of three size groups (10, 20 and 40 mm t.l.) marked with a fluorescent substance in the otolith were released in News Bay, Oita Prefecture, Japan, in July 1987 and June 1988, respectively; the aim was to estimate growth and mortality of different developmental stages. Of fish released in 1987 and 1988, 10 618 and 4413, respectively were recaptured during those two years. Released fish remained in the bay until the end of summer, and afterwards migrated out towards open waters. Fish of the 40-mm group released in 1987 grew to over 200 mm t.l. in one year. Mean growth rate for 19 days after release was higher in the 40-mm group (0.87 mm day−1) than in the 20-mm group (0.74mm day−1). Survival rates over 19 days were 59.0 and 10.1 % for 40-mm and 20-mm fish, respectively, in 1987, and those over 30 days were 69.2, 3.3 and 0.0% for 40-mm, 20-mm and 10-mm fish, respectively, in 1988. Cannibalism was indicated by the presence of marked otoliths for 20-mm fish in the stomachs of a few 40-mm individuals recaptured 2 days after release. Size-dependent growth and size-selective mortality were both noted in juvenile red sea bream, i.e. the relative size differential between larger and smaller individuals was maintained in the period between marking and recapture, and mortality was inversely proportional to size.