Modelando densidade e recrutamento de duas espécies de roedores da Caatinga durante maior evento de seca dos últimos 40 anos

• Autor(a) principal: Barreto, Rebeca Mascarenhas Fonseca
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/4953
• topic: Capture-mark-recapture; Spatial explicit capture-recapture; Population dynamic; Micro refuges; Captura-marcação-recaptura; Captura-recaptura espacialmente explicita; Dinâmica populacional; Micro refúgios; Roedores - Brasil, Nordeste; Roedores-Caatinga; Mudanças climáticas; Biodiversidade; CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA::ECOLOGIA APLICADA

Advances in research with rodent species from the Brazilian Caatinga Biogeographic Domain are concentrated, over the last decades, in Taxonomy and Phylogeography, raising questions about the need of better knowledge of their ecology strategies in dynamic populations. Studies carried on in arid, and semiarid environments around the world indicate that small rodent populations can maintain low levels of density and population growth for long periods. Such strategies occur mainly during periods of extreme drought when annual precipitations fall to atypical levels. Thereby, rainfall regime is a key factor to understand such process once rainfall stimulates primary production changing habitat and the spatial distribution of resources. In the present study, we first conducted a literature review to check the current knowledge status about the ecology of small rodents that inhabits the Caatinga Domain. In chapters 2 and 3 we analyzed, by traditional and spatial explicit capture-mark-recapture models, which processes may affect survival, recruitment and density of these two species during a drought event influenced by El Niño Southern Oscillation (ENSO), from 2012 to 2015. In chapter 1, according to the bibliographic search, we verified that the majority of publications including rodent species that occur in the Caatinga are about their Taxonomy and Systematic Phylogeny. Studies about Ecology are scarce, showing that there are knowledge gaps about small rodents ecological studies. So, the real priority is to focus studies about the ecological relationship and the process that mold their life histories, mainly because of the global climate change. We chose two species of endemic rodents of Brazilian semiarid region, the equimyid punaré rat (Thrichomys laurentius) and the cricetide red-nosed mouse (Wiedomys pyrrhorhinos). We found evidence that occasional rainfalls are the most important exogenous effect to maintain the studied species populations. However, these two species use distinct strategies to support their populations even under extremely low population growth rates. We noted that both species show different strategies to habitat spatial occupation through dry and wet seasons. Both species population densities fluctuate spatially which indicates the occupation of favorable micro refuges during dry periods. So, the understanding of particular climatic processes and the knowledge about a process which conduct the micro refuges selection of the small rodents of Caatinga Domain are key points to understand the population dynamic and maintenance of this group during drought events