Navegando por Autor "Vogt, Richard Carl"
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Item A large scale analysis of threats to the nesting sites of Podocnemis species and the effectiveness of the coverage of these areas by the Brazilian Action Plan for Amazon Turtle Conservation.(Journal for Nature Conservation,, 2021-06) Fagundes, Camila Kurzmann; Fath, Franciele; Cortes, Lara Gomes; Uhlig, Vívian; Andrade, Paulo C´esar Machado; Vogt, Richard Carl; Pezzuti, Juarez Carlos Brito; Marco Júnior, Paulo DeWe evaluated the vulnerability of nesting sites (sandbanks) available to Podocnemis expansa, P. unifilis and P. sextuberculata to human threats and the coverage of these areas by a public policy created to conserve turtles. Species distribution models were used to identify potential nesting areas in the Brazilian Amazon, where sandbanks were mapped through satellite imagery. Values of threats (deforestation, mining, dams and density of human communities) were normalized from 0 to 1 and summed in each 100 km2 pixel. We calculated the mean value of threats and sandbanks area for each basin. Basins with the greatest values for those variables were considered as the most vulnerable. We calculated the coverage of turtle nesting sites that have conservation actions in relation to the sandbanks available and if they are located in the most vulnerable basins. The areas of greatest gaps in conservation actions and vulnerability are located in the Tocantins-Araguaia basins and in rivers such as: Branco, Guapor´e, Amazonas, Solimoes, ˜ Madeira, Tapajos ´ and Xingu. Nesting sites included by the public policy covered 15.17 % of the number of basins and about 21 % of total sandbank areas, encompassing 11 % of the most vulnerable basins and 43 % of their sandbanks. We suggest the prioritization of conservation actions in areas of greatest gaps in conservation activities and vulnerability. In addition, we propose the articulation among institutions and the increase of initiatives of community-based conservation management to increase the geographical coverage of the greatest impacted regions.Item Don’t put all your eggs in one basket(Biological Conservation, 2019-10) Eisemberg, Carla Camilo; Vogt, Richard Carl; Balestra, Rafael Antônio M.; Reynolds, Stephen J.; Christian, Keith A. A.The Brazilian Government established the Amazon Turtle Project (Projeto Quelônios da Amazônia – PQA) in 1975 to monitor and protect the main nesting sites of Amazon River turtles. The PQA has become the largest-scale and longest-term wildlife conservation initiative in the Brazilian Amazon. We evaluated the outcomes of the PQA across 11 protected localities over 30 years (1977–2008). Inside the protected localities, one population of Podocnemis expansa has declined and four have seen an increase in numbers. The PQA conservation efforts for P. unifilis were not as successful as those of Podocnemis expansa, but were sufficient to stabilize or increase populations. These results suggest that there is a minimum effort necessary for positive conservation outcomes, which was not achieved for Podocnemis sextuberculata. Given the lack of correlation between initial nesting numbers and positive population trends, the current level of success in a given locality cannot be used as a tool to prioritize future protection efforts. We recommend that the PQA should maintain or increase its coverage due to the high levels of local unpredictability. If current harvest trends are maintained, it is likely the only surviving populations of P. expansa will be within protected areas. Considering the scope of the PQA and the period that it has been operational, it is surprising how little recognition it has received; the lack of national and international awareness of its achievements may be one of the main reasons behind the lack of support from the Brazilian Government. © 2019 Elsevier Ltd- Espécies-alvo do Plano de Ação Nacional para Conservação dos Quelônios Amazônicos(Ibama, 2019) Vogt, Richard Carl; Ferrara, Camila Rudge; Fagundes, Camila Kurzmann; Bataus, Yeda Soares de Lucena; Balestra, Rafael Antônio Machado; Lacava, Roberto Victor; Balestra, Rafael Antônio MachadoO capítulo 2 do Plano de Ação Nacional para Conservação dos Quelônios Amazônicos aborda a espécie Podocnemis expansa, conhecida como tartaruga-da-amazônia. Descreve suas características físicas, como a cabeça com escudo interparietal grande e variações de cor entre machos, jovens e fêmeas adultas. Também menciona a coloração da carapaça e do plastrão, destacando que é a maior espécie do gênero Podocnemis.
Item Population ecology of the freshwater turtle Mesoclemmys vanderhaegei (Testudines: Chelidae)(Herpetological Conservation and Biology, 2018-07-31) Brito, Elizângela Silva; Vogt, Richard Carl; Valadão, Rafael Martins; França, Leonardo Fernandes; Penha, Jerry Magno Ferreira; Strüssmann, ChristineWe sampled Mesoclemmys vanderhaegei in the Upper Paraguay River Basin, in the Cerrado ecosystem of Central Brazil. Populations were sampled between 2010 and 2013, and we used capture-mark-recapture methods to determine the catchability, density, population size structure, and sex ratio of the populations. We sampled two protected areas (Chapada dos Guimarães National Park [CGNP] and Serra das Araras Ecological Station [SAES]) and we captured 300 individuals (77 at CGNP and 223 at SAES) and made 343 recaptures in the two areas. Some individuals were recaptured more than once. We estimated population sizes to be 90 turtles at CGNP and 245 turtles at SAES. Sex ratio was not significantly different from 1:1 at CGNP, whereas at SAES there were more females than males. The population structure varied significantly between the two sampled populations with carapace lengths of turtles at CGNP normally distributed but not at SAES. Although both areas occur within the same ecosystem and are close to each other (180 km straight line distance), the populations possessed distinct demographic characteristics, possibly resulting from local patterns of environmental conditions and biological interactions.Item Roteiro para Inventários e Monitoramentos de Quelônios Continentais(Biodiversidade Brasileira, 2016) Balestra, Rafael Antônio Machado; Valadão, Rafael Martins; Vogt, Richard Carl; Bernhard, Rafael; Ferrara, Camila Rudge; Brito, Elizângela Silva; Arias, Robinson Botero; Malvásio, Adriana; Lustosa, Ana Paula Gomes; Souza, Franco Leandro de; Drummond, Gláucia Moreira; Bassett, Luis Antônio Bochetti; Bernhard, Rafael; Lustosa, Ana Paula Gomes; Souza, Franco Leandro de; Drummond, Gláucia Moreira; Bassetti, Luis Antônio Bochetti; Coutinho, Marcos Eduardo; Ferreira Junior, Paulo Dias; Campos, Zilca Maria da Silva; Mendonça, Sônia Helena Santesso Teixeira de; Rocha, João da Mata Nunes; Luz, Vera Lúcia FerreiraEm razão da falta de material específico de consulta que consolide as principais referências científicas e o acúmulo do conhecimento técnico sobre as metodologias de amostragem, coleta e análise de dados relativos aos quelônios continentais brasileiros, materializou-se este trabalho, há muito almejado pela sociedade interessada no assunto. Houve um grande esforço para compatibilizar metodologicamente as particularidades das espécies e ambientes em áreas com lacunas de amostragem, cujos parâmetros se adequam prioritariamente aos inventários e, em áreas com ocorrência conhecida de espécie(s) alvo de estudos de maior duração, aos monitoramentos populacionais. Sendo assim, essencialmente, este guia metodológico ou manual técnico inédito se constitui em roteiros de procedimentos fundamentados pela consolidação do estado da arte do conhecimento técnico-científico e pelas perspectivas, harmonizadas, dos principais grupos de pesquisa e entidades conservacionistas que atuam com esses animais. Essa iniciativa é oportuna, pois favorecerá a tão esperada padronização instrumental e analítica, segundo orientações validadas pelas experiências práticas dos autores, a serem adotados de forma consonante por diversas instituições ou grupos de pesquisa. Em consequência, poder-se-á integrar diferentes bancos de dados, compilar informações de séries históricas de dados de projetos correlatos, e assim, desenvolver análises comparativas das variáveis decorrentes dos componentes de pesquisa e conservação realizados de forma sistematizada por espécie, família, região, bioma etc., por meio de diferentes fontes de informação. E ainda, esta publicação tem o propósito de estimular a realização de estudos de caracterização do estado de conservação do grupo animal foco, especialmente em áreas protegidas, por meio da promoção de pesquisas básicas relativas à dinâmica de suas populações- Vulnerabilidade dos sítios de desova das espécies-alvo do PAN Quelônios Amazônicos e efetividade de políticas públicas(Ibama, 2019) Fagundes, Camila Kurzmann; Fath, Franciele; Côrtes, Lara Gomes; Guimarães Júnior, Robson; Andrade, Paulo César Machado; Vogt, Richard Carl; Pezzuti, Juarez Carlos Brito; Marco Júnior, Paulo de; Lacava, Roberto Victor; Balestra, Rafael Antônio MachadoO capitulo aborda a conservação e manejo de quelônios na Amazônia, destacando a importância de estudos locais e de longo prazo para propor soluções efetivas de mitigação e compensação ambiental. Ele menciona a sincronia entre o regime de vazante dos rios e o comportamento de nidificação da tartaruga da Amazônia, além de discutir a precisão dos modelos de distribuição de espécies. Também são abordadas variáveis climáticas importantes para a conservação, como índices de umidade, e o impacto de mudanças na legislação ambiental brasileira.
Item Vulnerability of Giant South American Turtle (Podocnemis expansa) nesting habitat to climate-changed-induced alterations to fluvial cicles.(Tropical Conservation Science, 2016) Eisemberg, Carla Camilo; Balestra, Rafael Antônio Machado; Famelli, Shirley; Pereira, Fernanda Freda; Bernardes, Virgínia Campos Diniz; Vogt, Richard CarlA change in seasonal flooding cycles in the Amazon may negatively impact nesting success of the Giant South American Turtle (Podocnemis expansa). Our aim was to devise a technique that could be replicated in the entire Amazon basin, for monitoring alterations in fluvial cycles and their effects on turtle nest mortality. We mapped the spatial distribution and height of P. expansa nests and tested the effects of different inundation scenarios within the Trombetas River Biological Reserve, Para state, Brazil. We also used historical data on water level and hatchling production to test whether the sharp decline in the Trombetas River P. expansa population over the past thirty years was related to detected changes in the flood pulse. Our models indicate that an increase of 1.5 m in the water level is sufficient to decrease the time of exposure to less than the minimum required for incubation and hatching (55 days above the water) in 50% of the nesting area. This model explains the low hatchling production in dry seasons when the total nesting site exposure was less than 200 days. Since 1971, there was na average decline of 15 days per decade in sandbank exposure during the nesting season (a total of 62 days from 1971 to 2015). However, the decrease in sandbank exposure was not significantly correlated with the sharp decline in hatchling production. Changes to the water cycle in combination with the main sources of decline (overharvest, construction of dams, and dredging of riverbeds) might have an accumulative effect on P. expansa populations.