Is 30 years enough time to niche segregation between a non-native and a native congeneric fish species? Evidences from stable isotopes

Abstract

Event Abstract Back to Event Is 30 years enough time to niche segregation between a non-native and a native congeneric fish species? Evidences from stable isotopes Gustavo Henrique Z. Alves1*, Gislaine I. Manetta1, Patrícia A. Sacramento1 and Evanilde Benedito1 1 Universidade Estadual de Maringá, Biology Dept., Brazil The invasion of non-native species that are phylogenetically similar to native species was observed in the Upper Paraná River following the construction of the Itaipu hydroelectric plant and subsequent removal of a natural geographic barrier (Sete Quedas Falls). Endemic fish species from the Lower Paraná River, such as the piranha Serrasalmus marginatus, successfully colonized the new environment. A few years later, S. marginatus had become the dominant species, while the prevalence of the congeneric species, Serrasalmus maculatus, had declined. Considering that the two piranha species naturally coexist in the Pantanal and that S. marginatus is a non-native species in the Upper Paraná River floodplain, we hypothesized that trophic niche overlap between Serrasalmus species only occurred in the Upper Paraná River floodplain due to short-term co-existence. The study area in which the isotopic niche overlap between S. maculatus and S. marginatus was evaluated consisted of two ponds located in different floodplains, the Pantanal and the Upper Paraná River. We used carbon and nitrogen stable isotope analysis to elucidate the differences in the energy intake by the native and non-native species. We used mixing models and calculated the isotopic niche area and niche overlap to infer the nature of the trophic interactions between the species in both habitats. According to the mixing model, the predominant source of carbon for both species was terrestrial. Nevertheless, in Upper Paraná River, the δ13C signature of the two species differed significantly and the non-native species had a greater niche width than the native species. In the Pantanal, there were no differences in δ13C, but the species differed with respect to δ 15N, and the niche widths were narrow for both species.Based on these results, it can be inferred that the species depend on different food sources. Piranhas obtain energy from distinct prey species, which probably consume resources from diverse food chains. Thus, the establishment of S. marginatus is probably driven by access to resources not used by the native species, by other niche dimensions not analyzed in this study (e.g., reproductive issues, competition among juveniles, etc.), or by other biotic interactions. Acknowledgements The authors thank Nupélia/UEM, the CNPq/SISBIOTA project, the Graduate Program in Ecology of Continental Aquatic Environments (Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais - PEA); CNPq/PELD for financial support and infrastructure to develop the study, and CNPq for the scholarship granted to Gustavo H. Z. Alves, and Patrícia A. Sacramento. This work was partially supported by CAPES, an organ of the Brazilian Government for the training of human resources. Keywords: Carbon, Nitrogen, Trophic niche, NON-NATIVE SPECIES, Serrasalmus Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Poster Presentation Topic: Ecology, Conservation and Invasive Species Citation: Alves GZ, Manetta GI, Sacramento PA and Benedito E (2015). Is 30 years enough time to niche segregation between a non-native and a native congeneric fish species? Evidences from stable isotopes. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.FMARS.2015.03.00246 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 30 Dec 2015; Published Online: 30 Dec 2015. * Correspondence: Dr. Gustavo Henrique Z Alves, Universidade Estadual de Maringá, Biology Dept., Maringá, Paraná, Brazil, alvesghz@yahoo.com.br Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Gustavo Henrique Z Alves Gislaine I Manetta Patrícia A Sacramento Evanilde Benedito Google Gustavo Henrique Z Alves Gislaine I Manetta Patrícia A Sacramento Evanilde Benedito Google Scholar Gustavo Henrique Z Alves Gislaine I Manetta Patrícia A Sacramento Evanilde Benedito PubMed Gustavo Henrique Z Alves Gislaine I Manetta Patrícia A Sacramento Evanilde Benedito Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.