A comparison of visual prey detection among species of piscivorous salmonids: effects of light and low turbidities
A comparison of visual prey detection among species of piscivorous salmonids: effects of light and low turbidities
复制标题
DOI：
10.1023/a:1025807711512
复制
发表时间：
2003-08-01
影响因子：
1.4
通讯作者：
Beauchamp, DA
中科院分区：
文献类型：
--
作者：
Mazur, MM;Beauchamp, DA
不同的视觉条件下，食鱼鲑对猎物鱼的反应距离的差异可以改变捕食者-猎物的相互作用。本文比较了三种常见于西部湖泊的食鱼性鲑科鱼类的反应距离，它们是：克氏虹鳟、虹鳟、克氏虹鳟。mykiss和非本地的查尔湖红点鲑（Salvelinus namaycush）。在受控的实验室环境中，测量鲑鱼猎物的反应距离作为光和浊度的函数。此外，在一定的光照水平下，实验测定了湖红点鲑对幼鲑的捕食率和游动速度。切喉鳟鱼和虹鳟鱼的反应距离迅速增加，随着光照水平的增加，达到相对恒定的反应距离在较高的光照水平。湖焦的反应距离相似，在较低的光水平的割喉鳟鱼和虹鳟鱼，但是，湖焦反应距离继续增加，随着光强度的增加，以渐近线的距离65%以上的割喉和虹鳟鱼。捕食率湖炭最暗的光水平低，迅速增加低光水平（0.50-0.75勒克斯）下，然后下降到一个中间率在所有较高的光水平。在极低的光照条件下，游泳的速度也迅速增加到一个峰值，并在光照水平高于1.00勒克斯下降到一个中间水平。这些结果表明，在饱和强度阈值以上，食鱼的湖炭鱼猎物在更大的距离比切喉鳟鱼和虹鳟鱼的反应。这些差异可能有助于解释下降的本地鳟鱼引进非本地湖炭在湖泊和水库的北美西部。
Differences in reaction distance to prey fish by piscivorous salmonids can alter predator-prey interactions under different visual conditions. We compared reaction distances of three piscivorous salmonids commonly found in western lakes: cutthroat trout, Oncorhynchus clarki utah, rainbow trout, O. mykiss, and the nonnative lake char, Salvelinus namaycush. Reaction distances to salmonid prey were measured as functions of light and turbidity in a controlled laboratory setting. In addition, predation rates and swimming speeds of lake char preying on juvenile cutthroat trout were measured experimentally under a range of light levels. Reaction distances for cutthroat trout and rainbow trout increased rapidly as light levels increased, reaching relatively constant reaction distances at higher light levels. Reaction distances for lake char were similar to cutthroat trout and rainbow trout at the lower light levels; however, lake char reaction distances continued to increase with increasing light intensity to asymptote at distances 65% higher than those for both cutthroat and rainbow trout. Predation rates by lake char were low for the darkest light levels, increased rapidly under low light levels (0.50-0.75 lx), and then declined to an intermediate rate at all higher light levels. Swimming speeds by lake char also increased rapidly from extremely low light conditions to a peak and declined to an intermediate level at light levels above 1.00 lx. These results suggest that, above the saturation intensity threshold, piscivorous lake char react to fish prey at greater distances than do cutthroat trout and rainbow trout. These differences may help explain the decline of native trout following the introductions of nonnative lake char in lakes and reservoirs of western North America.