The decline of the native fishes of lakes Victoria and Kyoga (East Africa) and the impact of introduced species, especially the Nile perch, Lates niloticus, and the Nile tilapia, Oreochromis niloticus
The decline of the native fishes of lakes Victoria and Kyoga (East Africa) and the impact of introduced species, especially the Nile perch, Lates niloticus, and the Nile tilapia, Oreochromis niloticus
复制标题
维多利亚湖和基奥加湖（东非）本土鱼类的减少以及外来物种的影响，特别是尼罗河鲈鱼、尼罗罗非鱼和尼罗罗非鱼
DOI：
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发表时间：
1990
影响因子：
1.4
通讯作者：
R. Ogutu
中科院分区：
文献类型：
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作者：
R. Ogutu
自本世纪初开始开发维多利亚湖和京加湖的渔业以来，东非维多利亚湖和Kyoga湖的许多本地鱼类物种已经减少，在某些情况下几乎完全消失。尼罗河鲈鱼是一种大型、贪婪的捕食者，大约在本世纪中叶与几种罗非鱼一起引入这些湖泊，被认为是导致几种罗非鱼种群减少的原因。但过度捕捞和不同物种之间的竞争似乎也是造成这种下降的原因之一。当尼罗河的栖息地变得很稳固时，当地罗非鱼物种的数量已经因为过度捕捞而减少。Labeo victorianus渔业在繁殖迁徙时对怀孕个体进行密集刺网后也出现恶化。然而，尼罗非鱼能够捕食那些被过度捕捞的物种，并可能阻止它们的种群从过度捕捞中恢复。尼罗河对虾的数量减少也是尼罗河的直接原因，在尼罗河栖息地形成之前，尼罗河流域的湖泊中就有大量的单色胺。即使没有尼罗河鲈鱼的捕食，也已经表明，如果在维多利亚湖建立拖网渔业，单色鱼也无法承受严重的商业开发。它们对人类食物的利用也带来了一些问题。本地罗非鱼物种的丰度也可能通过与具有类似生态要求的引进物种的竞争而减少。目前，尼罗河鲈鱼和一种引进的罗非鱼物种尼罗罗非鱼构成了维多利亚湖和京贺湖渔业的基础。
SynopsisThere has been a decline, and in some cases an almost total disappearance, of many of the native fish species of lakes Victoria and Kyoga in East Africa since the development of the fisheries of these lakes was initiated at the beginning of this century. The Nile perch, Lates niloticus, a large, voracious predator which was introduced into these lakes about the middle of the century along with several tilapiine species, is thought to have caused the reduction in the stocks of several species. But overfishing and competition between different species also appear to have contributed to this decline. By the time the Nile perch had become well established, stocks of the native tilapiine species had already been reduced by overfishing. The Labeo victorianus fishery had also deteriorated following intensive gillnetting of gravid individuals on breeding migrations. L. niloticus is, however, capable of preying on the species which haven been overfished and could have prevented their stocks from recovering from overfishing. L. niloticus is also directly responsible for the decline in populations of haplochromine cichlids which were abundant in these lakes before the Nile perch became established. Even without predation by Nile perch, it has been shown that the haplochromine cichlids could not have withstood heavy commercial exploitation if a trawl fishery had been established throughout Lake Victoria. Their utilisation for human food has also posed some problems. The abundance of the native tilapiine species may also have been reduced through competition with introduced species which have similar ecological requirements. At present, the Nile perch and one of the introduced tilapiine species, Oreochromis niloticus, form the basis of the fisheries of lakes Victoria and Kyoga.