Ecologia dos gatos-maracajás (Leopardus wiedii) e questões de conservação na Amazônia: Fatores de impacto, uso do habitat, atividade e relações interespecíficas na perspectiva da ecologia do medo

Abstract

The degradation of natural environments tends to alter the occurrence, distribution, and persistence, as well as existing coexistence and segregation relationships, which has led many to critical levels close to extinction. The problem becomes even more worrying when dealing with groups, such as carnivores, who naturally have low densities and require large larger extensions for survival. Even in areas of conservation units such as those in the Amazon region, there is still a bibliographic gap when dealing with ecological studies, such as distribution, co-occurrence patterns, structure, and dynamics of communities, which do not match the importance of species of this group not even with the biome. The subgroup of the small carnivores is even more disadvantaged due to their geographical overlap with larger species (e.g., Panthera onca) which receive greater investment in research projects and conservation plans. Given this, in this thesis, I investigated how biotic and abiotic predictors influenced spatiotemporal patterns in the occurrence and distribution of some small Amazonian carnivores and how they relate to the species focus of the study, the little threatened feline, the margay Leopardus wiedii. This knowledge was generated from a database that used the camera traps method, the result of a collaborative approach between national and international institutions, aiming to pioneer long-term and large-scale studies with terrestrial vertebrate species in areas of relevant interest for the conservation of the Amazon biome. Specifically: 1) I evaluate activity patterns, plasticity levels, and temporal overlap between five species of Amazonian mesocarnivores and their prey in a disturbance gradient that included 17 Protected Areas; 2) the use of habitat and subsequent spatial co-occurrence between two species of small amazonian felines using a hierarchical approach with occupancy models and, finally 3) the comparative use of habitat by the feline focus of the study and other members of the assemblage of mammals among different Amazonian forest types, represented here by the flooded forests of igapó and unflooded forests of terra firme. The main conclusions were that: 1) although the standards of activity displayed by species are shaped by long-term evolutionary forces, they also appear to be adjusted in the short term for some species in response to current environmental changes, possibly to maximize the foraging efficiency and reduce the chances of agonistic encounters; 2) The results of interactions between small carnivores Leopardus wiedii and Leopardus pardalis were mediated by environmental (elevation) and anthropogenic (accessibility by humans) factors associated with the space partitioning structure of these felids, a finding that is in line with competitive exclusion principle. The study also shows the importance of a collaborative approach by combining local databases for a better understanding of coexistence mechanisms at broader scales, such as the ones addressed in this study; and 3) even poor areas in nutrients, such as igapó flooded forests, are critical environments for maintenance not only of the focus species of the study but also in the structuring of the mammalian assembly as a whole. The results also highlight the importance of maintaining the mosaic of natural habitats on the scale of the entire landscape, with large drainage basins representing management units that provide large enough areas to support a series of ecological processes. This thesis thus sought to elucidate some of the intriguing coexistence strategies of a group of small carnivores in a highly relevant biome for their conservation and the need for collaborative approaches for standardized monitoring as an essential tool for understanding structuring processes community and potential effects of environmental changes.