Competitive interactions between the rotifer Synchaeta oblonga and the cladoceran Scapholeberis kingi Sars
Competition experiments showed that the small cladoceran Scapholeberis kingi rapidly excluded the rotifer Synchaeta oblonga from mixed-species cultures, but was itself unaffected by the presence of S. oblonga. Short-term experiments testing the effect of S. kingi on the survivorship and reproduction of S. oblonga showed that the former imposed a high mortality on the latter, even though shared food resources were abundant. These results indicate that adult S. kingi mechanically interferes with S. oblonga either by ingesting, or by rejecting in a damaged condition, individuals swept into its branchial chamber. In contrast to many other small species of cladocerans, and like large species of Daphnia, S. kingi has the potential to markedly suppress populations of some rotifer species through a combination of interference and exploitative competition.
Key wordscompetition interference Scapholeberis Synchaeta zooplankton
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