Seasonal population and individual niche dynamics in a tetra fish in the Pantanal wetlands

dc.contributor.authorCosta-Pereira, Raul [UNESP]
dc.contributor.authorTavares, Luiz E.R.
dc.contributor.authorde Camargo, Plínio Barbosa
dc.contributor.authorAraújo, Márcio S. [UNESP]
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.contributor.institutionRice University
dc.contributor.institutionUniversidade Federal de Mato Grosso do Sul (UFMS)
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.description.abstractIn seasonal tropical regions, rainfall and/or temporary floods during the wet season generally increase the abundance and diversity of food resources to many consumers as compared to the dry season. Therefore, seasonality can affect intraspecific competition and ecological opportunity, which are two important ecological mechanisms underlying population and individual niche variations. Here, we took advantage of the strong seasonality in the Pantanal wetlands to investigate how within- and between-individual diet variations relate to seasonal population niche dynamics of the tetra fish Astyanax lacustris. We quantified dietary niche using gut contents and stable isotopes. Tetras had higher gut fullness and better body condition in the wet season, suggesting that competition is more intense in the dry season. The population niche was broader in the wet season due to an increase in diet divergence between individuals, in spite of potential stronger competition in the dry season. We posit that low ecological opportunity in the dry season limits the diversifying effect of intraspecific competition, constraining population niche expansion. Our results add new insights on how seasonality affects population and individual diets, indicating that intraspecific competition and ecological opportunity interact to determine temporal niche variations in seasonal environments.en
dc.description.affiliationUniversidade Estadual Paulista (UNESP) Instituto de Biociências
dc.description.affiliationPrograma de Póˇs-graduação em Ecologia e Biodiversidade Instituto de Biociências UNESP
dc.description.affiliationBioSciences Rice University
dc.description.affiliationCentro de Ciências Biológicas e da Saúde Universidade Federal de Mato Grosso do Sul
dc.description.affiliationLaboratório de Ecologia Isotópica Centro de Energia Nuclear na Agricultura Universidade de São Paulo
dc.description.affiliationUnespUniversidade Estadual Paulista (UNESP) Instituto de Biociências
dc.description.affiliationUnespPrograma de Póˇs-graduação em Ecologia e Biodiversidade Instituto de Biociências UNESP
dc.description.sponsorshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
dc.description.sponsorshipConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
dc.description.sponsorshipIdFAPESP: 2010/15567-8
dc.description.sponsorshipIdFAPESP: 2014/20924-5
dc.description.sponsorshipIdCNPq: 311567/2013-4
dc.identifier.citationBiotropica, v. 49, n. 4, p. 531-538, 2017.
dc.rights.accessRightsAcesso restrito
dc.subjectindividual specialization
dc.subjectintraspecific variation
dc.subjectmixing models
dc.subjectresource fluctuation
dc.subjecttrophic niche
dc.titleSeasonal population and individual niche dynamics in a tetra fish in the Pantanal wetlandsen