Slower growth of farmed eels stocked into rivers with higher wild eel density
Slower growth of farmed eels stocked into rivers with higher wild eel density
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野生鳗鱼密度较高的河流中养殖鳗鱼的生长速度较慢
DOI：
10.1111/jfb.15131
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发表时间：
2022
影响因子：
2
通讯作者：
Kaifu Kenzo
中科院分区：
文献类型：
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作者：
Wakiya Ryoshiro;Itakura Hikaru;Hirae Tatsumu;Igari Tadamitsu;Manabe Miyuki;Matsuya Noriaki;Miyata Katsushi;Sakata Masayuki K.;Minamoto Toshifumi;Yada Takashi;Kaifu Kenzo
养殖的鳗鱼经常被放养到天然淡水中，以增加鳗鱼资源，但人们对这些鳗鱼放养后会发生什么，或者它们与野生鳗鱼的相互作用知之甚少。最近的一项研究发现，养殖的日本鳗鱼在与野生鳗鱼一起饲养时，存活率和生长率都很低，这表明野生鳗鱼可能通过种内竞争干扰了养殖和放养的鳗鱼的生存和生长。为提高鳗鱼放养效率，采用标记-再捕获方法，比较了不同野生鳗鱼密度的4条河流养殖放养日本鳗的生长情况。根据放养后2年的复捕调查发现，不同河流养殖放养鳗鱼的密度没有显著差异。在野生鳗鱼密度较低的河流中，养殖和放养鳗鱼的日生长率显著高于野生鳗鱼密度较高的河流中饲养的鳗鱼。与表现出久坐行为的野生鳗鱼相比，养殖和放养的鳗鱼向下游移动的距离要大得多。这项研究和之前的研究表明，将养殖的鳗鱼放养到存在自然招募的野生鳗鱼的水体中的有效性仍然存在重大问题。
Farmed anguillid eels are frequently stocked into natural fresh waters to enhance eel resources, but little is known about what happens to these eels or their interactions with wild eels after stocking. A recent study observed a depressed survival and growth rate of farmed Japanese eels when they were reared with wild eels, which indicated that wild eels might interfere with the survival and growth of farmed‐and‐stocked eels through intraspecific competition. To contribute to improving eel stocking efficiency, the growth of farmed‐and‐stocked Japanese eels was compared among four rivers with different wild eel densities using mark‐and‐recapture studies. Based on the 2‐year recapture survey after stocking, it was found that the density of the farmed‐and‐stocked eels was not significantly different among rivers. The daily growth rates of farmed‐and‐stocked eels in the rivers with lower wild eel density were significantly higher than those of the eels stocked into the rivers with higher wild eel density. The farmed‐and‐stocked eels moved significantly greater distances downstream than wild eels that showed sedentary behaviour. This and previous studies indicate that significant questions remain about the effectiveness of stocking farmed eels into water bodies where naturally recruited wild eels are present.