Exotic invaders gain foraging benefits by shoaling with native fish
Abstract
Freshwater habitats are under increasing threat due to invasions of exotic fish. These invasions typically begin with the introduction of small numbers of individuals unfamiliar with the new habitat. One way in which the invaders might overcome this disadvantage is by associating with native taxa occupying a similar ecological niche. Here we used guppies (Poecilia reticulata) from a feral population in Mexico to test the prediction that exotic shoaling fish can associate with heterospecifics, and that they improve their foraging efficiency by doing so. Guppies have invaded the Mexican High Plateau and are implicated in the declines of many native topminnow (Goodeinae) species. We show that heterospecific associations between guppies and topminnows can deliver the same foraging benefits as conspecific shoals, and that variation in foraging gains is linked to differences in association tendency. These results uncover a mechanism enabling founding individuals to survive during the most vulnerable phase of an invasion and help explain why guppies have established viable populations in many parts of Mexico as well in every continent except Antarctica.
Citation
Camacho Cervantes , M , Macias Garcia , C D J , Ojanguren , A F & Magurran , A 2014 , ' Exotic invaders gain foraging benefits by shoaling with native fish ' , Royal Society Open Science , vol. 1 , no. 3 , 140101 . https://doi.org/10.1098/rsos.140101
Publication
Royal Society Open Science
Status
Peer reviewed
ISSN
2054-5703Type
Journal article
Rights
© 2014 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
Description
We thank the University of St Andrews School of Biology Research Committee for funding. M.C.-C. thanks Topo Cortés and Bati Loch for fieldwork assistance. A.E.M. acknowledges the ERC (project BioTIME 250189) and the Royal Society.Collections
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