Research
| Title： | Do sympatric transgenic and non-transgenic common carps partition the trophic niche? A whole-lake manipulation study |
|---|---|
| First author： | Wang, Kang; Sha, Yongcui; Xu, Jun; Zhang, Tanglin; Hu, Wei; Zhu, Zuoyan |
| Journal： | SCIENCE OF THE TOTAL ENVIRONMENT |
| Years： | 2021 |
| DOI： | 10.1016/j.scitotenv.2021.147516 |
| Abstract： | Genetically modified organisms (GMO) are a potential driver of human-induced global change and interactions occurring among GMOs and non-GMOs have important implications for ecosystem structure and functioning. Genetically modified fish (transgenic fish) can improve the production and characteristics of conventional fish strains currently exploited in aquaculture, but their ecological impacts on local food web remain less studied. We settled all-fish growth hormone gene-transgenic and non-transgenic common carp (carp(T) and carp(NT)) sympatrically in an artificial lake, and used stable isotope analysis to test the hypothesis that carp(T) and carp(NT) alter their trophic niche to facilitate coexistence through local niche partitioning. A general paradigm for coexistence of carp(NT) and carp(T) in this study was that carp(NT) increased the use of low-quality food resources (such as submerged plants) to mitigate the competition for limited resources (i.e., zoobenthos) resulting from niche partitioning. This change resulted in an enlarged niche width of carp(NT) and increased the niche overlap with its sympatric competitor, that is, carp(T), which led to an increase in the individual specialization within the population to enhance resource use efficiency. This study represents the first controlled empirical test of the trophic interactions between competitive coexisting transgenic and non-transgenic organisms at population and individual levels. Our results indicate that competitive niche partitioning operating between carp(NT) and carp(T) shifts through time, emphasizing the importance of changing interspecific interactions when considering the ecological risk of transgenic species release, and it can be inferred that it is difficult for the escaped carp(T) to achieve the form of an explosive and most successful population than the wild carp. (C) 2021 Elsevier B.V. All rights reserved. |
