Ontogenetic changes in diel activity, food habits and spatial distribution of juvenile and adult creek chub, Semotilus atromaculatus
Ontogenetic changes in diel activity, food habits and spatial distribution of juvenile and adult creek chub, Semotilus atromaculatus
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幼年和成年溪鲢 (Semotilus atromaculatus) 昼夜活动、食物习惯和空间分布的个体发育变化
DOI：
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发表时间：
1984
影响因子：
1.4
通讯作者：
G. J. FitzGerald
中科院分区：
文献类型：
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作者：
P. Magnan;G. J. FitzGerald
幼鱼（Semotilus atromaculatus）在生态学上与成鱼不同。它们以小型猎物（双翅目成虫和水生鞘翅目成虫）为食，主要分布在曲海寡营养湖泊的浅海水域（0.8 m深）。成虫主要在夜间活动，以较大的猎物（双翅目幼虫、双翅目蛹和蜉蝣目幼虫）为食，分布在较深的水域（1.2、2.0和2.9 m）。幼鱼和成鱼的饮食有10%的重叠。我们发现，在302个样本中，只有5个样本胃中有16个幼鱼，没有一个样本胃中有成年鱼。实验结果表明，在低光强（0.17勒克斯）条件下，成年鱼的取食效率与高光强（22勒克斯）条件下相同。讨论了几种可能的假说来解释成年和幼年小溪俱乐部表现出的两种不同策略的演变。
SynopsisJuvenile creek chub, Semotilus atromaculatus, differed ecologically from adults. They were essentially diurnal, fed on small prey (adult diptera and aquatic adult coleoptera) and were found mainly in shallow littoral water (0.8 m depth) of a Québec oligotrophic lake. In contrast, adults were principally nocturnal, fed on larger prey (Gammaridae, diptera larvae, diptera pupae and ephemeroptera larvae) and were found in deeper water (1.2, 2.0 and 2.9 m depth). The overlap in diet between juvenile and adult fish was 10 percent. We found that predation by brook charr, Salvelinus fontinalis, upon creek chub was low, as only 5 chart stomachs of the 302 examined contained a total of 16 juvenile chub and none contained adult chub. Laboratory observations revealed that under low light intensity (0.17 lux) adult creek chub fed as efficiently as under high light intensity (22 lux). Several possible hypotheses to explain the evolution of the two different strategies exhibed by adult and juvenile creek chub are discussed.