62 research outputs found

    The northernmost haulout site of South American sea lions and fur seals in the western South Atlantic

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    We present estimates of the seasonal and spatial occupation by pinnipeds of the Wildlife Refuge of Ilha dos Lobos (WRIL), based on aerial photographic censuses. Twenty aerial photographic censuses were analysed between July 2010 and November 2018. To assess monthly differences in the numbers of pinnipeds in the WRIL we used a Generalized Linear Mixed Model. Spatial analysis was carried out using Kernel density analysis of the pinnipeds on a grid plotted along the WRIL. Subadult male South American sea lions (Otaria flavescens) were the most abundant pinniped in the WRIL. Potential females of this species were also recorded during half of the census. The maximum number of pinnipeds observed in the WRIL was 304 in September 2018, including an unexpected individual southern elephant seal (Mirounga leonina), and a high number of South American fur seal yearlings (Arctocephalus australis). However, there was no statistically significant difference in counts between months. In all months analysed, pinnipeds were most often found concentrated in the northern portion of the island, with the highest abundances reported in September. This study confirms the importance of the WRIL as a haulout site for pinnipeds in Brazil, recommends that land research and recreational activities occur in months when no pinnipeds are present, and encourages a regulated marine mammal-based tourism during winter and spring months.Fil: Procksch, Natália. Universidad de Vale do Rio dos Sinos; BrasilFil: Grandi, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Ott, Paulo Henrique. Universidade Estadual Do Rio Grande Do Sul; Brasil. Grupo de Estudos de Mamíferos Aquáticos Do Rio Grande Do Sul (GEMARS); BrasilFil: Groch, Karina. Instituto Australis de Pesquisa E Monitoramento Ambiental. Projeto Baleia Franca; BrasilFil: Flores, Paulo A. C.. Centro Mamíferos Aquáticos, Currently at Área de Proteção Ambiental; BrasilFil: Zagonel, Marcelo. Universidad de Vale do Rio dos Sinos; BrasilFil: Crespo, Enrique Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Machado, Rodrigo. Grupo de Estudos de Mamíferos Aquáticos Do Rio Grande Do Sul (GEMARS); BrasilFil: Pavez, Guido. Universidad de Valparaiso; ChileFil: Guimarães, Murilo. Universidade Federal do Rio Grande do Sul; BrasilFil: Veronez, Maurício. Universidad de Vale do Rio dos Sinos; BrasilFil: de Oliveira, Larissa Rosa. Grupo de Estudos de Mamíferos Aquáticos Do Rio Grande Do Sul (GEMARS); Brasil. Universidad de Vale do Rio dos Sinos; Brasi

    Unexpected species diversity in electric eels with a description of the strongest living bioelectricity generator

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    Is there only one electric eel species? For two and a half centuries since its description by Linnaeus, Electrophorus electricus has captivated humankind by its capacity to generate strong electric discharges. Despite the importance of Electrophorus in multiple fields of science, the possibility of additional species-level diversity in the genus, which could also reveal a hidden variety of substances and bioelectrogenic functions, has hitherto not been explored. Here, based on overwhelming patterns of genetic, morphological, and ecological data, we reject the hypothesis of a single species broadly distributed throughout Greater Amazonia. Our analyses readily identify three major lineages that diverged during the Miocene and Pliocene—two of which warrant recognition as new species. For one of the new species, we recorded a discharge of 860 V, well above 650 V previously cited for Electrophorus, making it the strongest living bioelectricity generator. © 2019, The Author(s)

    Pervasive gaps in Amazonian ecological research

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