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URI permanente desta comunidadehttps://bdc.icmbio.gov.br/handle/cecav/1401

Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios

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Resultados da Pesquisa

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    Using genetics to plan black rat (Rattus rattus) management in Fernando de Noronha archipelago, Brazil.
    (Perspectives in Ecology and Conservation, 2020) Gatto-Almeida, Fernanda; Pichlmueller, Florian; Micheletti, Tatiane; Abrahão, Carlos R.; Mangini, Paulo R.
    Invasive mammals such as rats are associated with negative impacts on native fauna and their eradication on islands around the world has been proved to result in substantial conservation gains. Fernando de Noronha is an archipelago located off the north-east coast of Brazil and has records of native fauna negatively impacted by introduced rats. We used D-Loop sequences and 14 microsatellite markers to investigate gene flow between three populations of Rattus rattus across two islands of Fernando de Noronha. Using both methods we found very great differentiation between the two islands, indicating very low or no gene flow. Our findings suggested if Rata Island were cleared of rats it would have a low probability of reinvasion occurring from the main island. Thus, we recommend an eradication program be implemented on Rata Island following the successful program on nearby Meio Island. © 2020 Associac¸ ao˜ Brasileira de Ciencia ˆ Ecologica ´ e Conservac¸ ao. ˜ Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).
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    Diet of invasive cats, rats and tegu lizards reveals impact over threatened species in a tropical island.
    (Perspectives in Ecology and Conservation, 2020) Gaiotto, Juliana Vallim; Abrahão, Carlos Roberto; Dias, Ricardo Augusto; Bugoni, Leandro
    Vertebrates introduced in non-native habitats have contributed to several extinctions in the modern era, with direct effects mainly over birds, mammals and reptiles on islands. Fernando de Noronha Archipelago, in tropical Atlantic Ocean, is a World Heritage natural site, holding the most diverse breeding seabird community off Brazil, in addition to endemic landbirds and reptiles. It also holds invasive black rats (Rattus rattus), tegu lizards (Salvator merianae) and feral cats (Felis catus), among the 26 exotic species reported in the archipelago, all of which are species with potentially high impact upon native fauna. Aiming to assess the role of exotic vertebrates on the fauna, we investigated their diets through stomach content and scat analysis, and stable isotope analysis (SIA) followed by isotopic mixing models. The main food items for tegu lizards were fruits, with relative importance (Prey-specific Index of Relative Importance – %PSIRI) of 41.3%, and the endemic Noronha skink (Trachylepis atlantica; 19.6%) and for black rats was Noronha skink (30.3%). The diet of feral cats was composed by rodents (31.6%), birds (28.6%) and Noronha skink (18.8%). SIA and Bayesian mixing models provided evidences that invasive species use marine matter to synthesize tissues, probably derived directly or indirectly from seabird colonies. This study demonstrated that exotic species feed on other exotic, as well as endemic species. The most heavily impacted species was the endemic Noronha skink. We demonstrated the predation pressure of exotic fauna upon endemic vertebrates, and strongly recommend the implementation of an invasive species control and eradication plan.