Dear all, my co-authors and I are pleased to announce a new publication on dietary estimates for franciscanas, Pontoporia blainvillei, using the stable isotope approach.
Troina, G., Botta, S., Secchi, E. R., and Dehairs, F. 2016. *Ontogenetic and sexual characterization of the feeding habits of franciscanas, **Pontoporia blainvillei**, based on tooth dentin carbon and nitrogen stable isotopes. *Marine Mammal Science. DOI: 10.1111/mms.12316 ABSTRACT: We assessed the feeding habits of franciscanas (*Pontoporia blainvillei*) from southern Brazil through carbon and nitrogen stable isotopes measured in the tooth dentin of dolphins from different age classes. Generalized additive models were fitted to assess whether sex, age, and total body length explained changes in franciscanas isotope ratios. Bayesian isotope mixing models were applied to estimate the contributions of prey items, selected based on stomach content analysis (SCA), to franciscanas' diet. Different trophic enrichment factors (TEF) were applied and the results were compared using Bhattachayya's coefficient index to test for differences in model outputs and to define the best TEF for franciscanas. We found different relative importance of the main prey between the methods, and the contribution by squids could be lower than suggested by SCA. Because the dentin deposited during nursing seems to influence the isotopic ratios of juveniles, caution is recommended when interpreting dietary estimates based on whole tooth samples. This study is the first to characterize ontogenetic shifts in franciscanas' feeding habits using stable isotope analysis (SIA) and testing different TEF values. SIA and SCA complement each other in dietary studies, mitigating potential biases resulting from the use of each method separately. The article is available for download on http://onlinelibrary.wiley.com/doi/10.1111/mms.12316/abstract Or a PDF can be provided via email request: genyffertro...@gmail.com Cheers, Genyffer -- MSc. Genyffer Troina Doutoranda no Programa de Pós Graduação em Oceanografia Biológica Laboratório de Ecologia e Conservação da Megafauna Marinha (ECOMEGA) Instituto de Oceanografia – IO/Universidade Federal do Rio Grande - FURG Rio Grande/RS (CEP 96201900), CP 474, BRAZIL Analytical, Environmental and Geo-Chemistry Department, Earth System Sciences Research Group, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Phone: (+55) 53 81189816/(+32)491/897081 genyffertro...@gmail.com CV: http://lattes.cnpq.br/3997346742040354 <https://wwws.cnpq.br/cvlattesweb/PKG_MENU.menu?f_cod=95BCF6774B1701C4C08659078AEA342D#>
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