Livros e Publicações
URI permanente para esta coleçãohttps://bdc.icmbio.gov.br/handle/cecav/1481
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Item Thermal constraints explain and distribution of the climate telict lizard Colobosauroides carvalhoi (Gymnophthalmidae) in the semiarid Caatinga.(South American Journal of Herptology, 2018) Recoder, Renato Sousa; Magalhães-Júnior, Arnaldo; Rodrigues, Juliana; Pinto, Hugo Bonfim de Arruda; Rodrigues, Miguel Trefaut; Camacho, AgustínWithin the semiarid Caatinga of Brazil, a biome dominated by a xeric arboreal-arbustive vegetation, many lizards are restricted to forest remnants associated with highlands. Although critical for conservation, data to understand the constraints on the distribution of those potential climate relicts are almost nonexistent. Here, we studied aspects of the ecology of the relict forest lizard Colobosauroides carvalhoi (Gymnophthalmidae) in the Caatinga of southern Piauí, northeastern Brazil. We combined data obtained through active sampling with voluntary thermal maximum (VTM) and measurements of environmental temperatures made in different habitats, microhabitats, and seasons to test the prediction that thermal constraints explain the local distribution and abundance of this species. In four field trips, we captured 22 individuals in pitfall traps and 93 in active searches, all in canyon-like valleys covered with semi-deciduous forests. Using plot sampling, we observed that density decreased as distance from rock cliffs increased. Density did not differ among sampling localities but varied among seasons. Field body temperatures were similar to soil temperatures under the leaf litter and lower than air and surface temperatures. Environmental temperatures in forests were lower than the VTM estimated for C. carvalhoi, especially under the leaf litter. Nevertheless, environmental temperatures usually exceeded the VTM at forest borders and in caatingas, in which the species was absent. Our results confirm that C. carvalhoi is spatially constrained to patches of semi-deciduous forests and suggest that its low thermal tolerance likely prevents it from occurring or dispersing through xeric habitats that predominates in Caatinga.Item Assessing Brazilian turtles’ vulnerability BY USING species distribution models AND dispersal constraints(Biodiversity and Conservation, 2024-01-27) Pinto, Hugo Bonfim de Arruda; Valadão, Rafael Martins; Andrade, André Felipe Alves de; Batista, Flavia Regina de Queiroz; Marco Júnior, Paulo DeMost assessments of the conservation status of Brazilian turtles use the IUCN geographic range criteria performed by the Minimum Convex Polygon (MCP). This technique often leads to over- or under-estimating the geographic distribution of rare, vulnerable, or endangered species. We aimed to demonstrate that using Species Distribution Models (SDM) on the geographic range assessment of turtles could be more accurate than using the minimum polygon convex. We reduced overestimation of species’ extent of occurrence by adding dispersal constraints, which avoids under- or over-estimating the impact of threatening events. The extent of occurrence derived from MCP was 31% higher than SDM on average, ranging from 4 to 311% higher. Using remaining habitat variables, we found that habitat loss within the predicted extent of occurrence increased by 79% from 1985 to 2019, and inferred population fragmentation increased by 161%. The distribution of turtles Acanthochelys radiolata, Acanthochelys spixii, Hydromedusa maximiliani, Hydromedusa tectifera, Mesoclemmys vanderhaegei, Phrynops williamsi, and Ranacephala hogei is severely fragmented, with most of their extent of occurrence being split into patches that are unavailable to the species persistence. Our findings highlight the importance of using SDM combined with dispersal constraints, which may further benefit from future information about the dispersal capacity of turtles. Furthermore, adding environmental layers to this combination makes it possible to discuss processes affected by habitat fragmentation, such as the fragmentation of species populations, an aspect essential to evaluate population viability and local extinctions.