[MARMAM] New publication: The isotopic niche of a tropical cetacean community
Deal all, My co-authors and I are pleased to share our new contribution: M.C. Neves, M. Vannuci-Silva, G. Montanini, A.F. Azevedo, J. Lailson-Brito, T.L. Bisi (2023). From narrow and overlapped to wide and segregated: The isotopic niche of a tropical cetacean community. Ecological Indicators. Abstract Species in sympatry can coexist due to some degree of niche partitioning. Four cetacean species, Guiana (Sotalia guianensis), franciscana (Pontoporia blainvillei), Atlantic spotted (Stenella frontalis), and rough-toothed dolphins (Steno bredanensis), frequently occur in Ilha Grande Bay (RJ), with three of them presenting residence pattern. This tropical bay is considered a biodiversity hotspot and preserved by marine protected areas, though located in a highly developed region of the Southwestern Atlantic Ocean. To verify niche partitioning and segregation in these species and to explore the trophic structure of this cetacean community, their isotopic niches were investigated through carbon (δ13C) and nitrogen (δ15N) stable isotopes in the muscle of specimens stranded in the region between 2012 and 2022. The rough-toothed dolphin had the largest niche area and high segregation. On the other hand, there was a high niche overlap between the species that have site fidelity patterns in the bay. The Atlantic spotted dolphin had the highest values for almost all the Layman metrics, a large niche area, and trophic diversity; the Guiana dolphin explored a diverse variety of resources, and the franciscana dolphin presented the narrowest and most overlapped niche and the lowest niche diversification. This is the first study to access the trophic ecology of this cetacean community. Our results indicate that the region is an important foraging area for three of the studied species, with a high diversity and availability of resources that might enable the high niche overlap observed for resident species. The findings for the threatened and small franciscana population in this recently discovered habitat bring concern. Therefore, the area deserves conservation attention to prevent anthropogenic stressors from interfering in the relationship balance between these sympatric predators. The article can be downloaded at https://doi.org/10.1016/j.ecolind.2023.110711 Please feel free to email me if you have any questions: maricne...@gmail.com Kind regards, Mariana --- Msc. Mariana Cappello Neves Ph.D. student Programa de Pós-graduação em Oceanografia - UERJ Laboratório de Mamíferos Aquáticos e Bioindicadores (MAQUA) maqua.com.br ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] New publication: Humpback Whale (Megaptera novaeangliae) Resighted Eight Years After Stranding
On behalf of my co-authors I would like to share our recent note on a successful rescue of a humpback whale published in Aquatic Mammals. Mariana C. Neves, Hugo G. Neto, Ana L. Cypriano-Souza, Berenice M. G. da Silva, Shirley P. de Souza, Milton C. C. Marcondes, and Marcia H. Engel. (2020). Humpback Whale (Megaptera novaeangliae) Resighted Eight Years After Stranding. Aquatic Mammals, 46(5), 483-487. DOI: https://doi.org/10.1578/AM.465.2020.483 Abstract: Refloating is a common strategy to deal with stranded whales, but resighting reports are rare, especially after long periods of several years. Here, we report the longest known period between rescue and resighting of an adult male humpback whale (8 years) identified through DNA analyzes. The whale stranded in a beach (Ubatuba, São Paulo state, Brazil) in the end of the breeding season (November 2000), and was resighted after eight years within the main Southwest Atlantic breeding area (Abrolhos Bank, Bahia state, Brazil) as part of a competitive group (July 2008). The novel refloating procedure involved the use of a rope behind the pectoral fin region. Our report provides useful information for similar operations and clarifies conditions under which refloating of large cetaceans is worth-attempting, such as whale’s physical condition, site characteristics,equipment availability, and adequate procedures. The note is available at <https://doi.org/10.1578/AM.46.5.2020.483> Please email me if you have any questions or difficult in assessing it: maricne...@gmail.com Best regards, Mariana -- Msc. Mariana Cappello Neves Ph.D. student Programa de Pós-graduação em Oceanografia, Universidade do Estado do Rio de Janeiro - UERJ Laboratório de Mamíferos Aquáticos e Bioindicadores (MAQUA) Rua São Francisco Xavier, 524, Rio de Janeiro - RJ, Brasil 20550-013 Tel: +55 21 99867-9542 <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail> Livre de vírus. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail>. <#m_1479554834122672321_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
