Avaliação e implicações do estresse do turismo de interação e intervalo de referência bioquímica do sangue de Melanosuchus niger e Caiman crocodilus no Parque Nacional de Anavilhanas, Amazônia Central brasileira

Abstract

Crocodilians are individuals with complex and cryptic biology, top predators, and are of great economic and ecological importance in the natural systems where they occur or when they are introduced. The equatorial region is home to the greatest diversity of crocodilians in the world. Brazil is one of the countries with the greatest diversity of crocodilians. There are five species with a wide natural distribution, which are popularly called caimans. Four of these species occur in the Brazilian Amazon region, two of which, the Black caiman (Melanosuchus niger) and the Spectacled caiman (Caiman crocodilus), are the most abundant and most studied to date. Historically, they are important in the production chain, as they have been subject to legal/illegal economic exploitation in the state of Amazonas for more than half a century, albeit in a destructive way in order to make use of their by-products. Today, wildlife tourism is an alternative for non-destructive economic exploitation combined with conservation. In this sense, the growing demand for interaction tourism with Amazonian caimans has raised concerns about the effects of interaction tourism on caimans. However, it is difficult to assess these effects due to the lack of appropriate and applied methods, as well as due to the lack of reference intervals for blood biochemical parameters for M. niger and C. crocodilus, which are of parameters importance when it comes to assessing the direct effects not only of tourism or other human interventions, but also in veterinary clinical analyses as well as in the interpretation of animal biological status. In this context, the present thesis investigated the effect of tourism on caiman interaction and recorded reference intervals for 11 blood biochemical parameters of M. niger and C. crocodilus populations in the Anavilhanas National Park, on the lower Negro River. The first chapter presents an assessment of the direct physiological stress of tourist interaction with M. niger and C. crocodilus. The second chapter establishes reference intervals for 11 blood parameters for M. niger and C. crocodilus. Finally, the results found in this thesis can support decisions that can direct the course of sustainable, non-destructive caiman management, caiman interaction tourism, as well as assist veterinarians and wildlife biologists in clinical diagnoses and assessment of the physical condition of caimans. I hope that this thesis will encourage further research as a result of the findings presented here.