Ecologia e conservação da raposa-do-campo (Lycalopex vetulus) e interações com canídeos simpátricos em áreas antropizadas do Brasil

Abstract

Wild canids have the widest distribution than any other group of carnivores on the planet. Such characteristic makes them an important part in the dynamics of a variety of ecosystems. To better understand the evolutionary history of South American canids and how they share resources along disturbed areas, this study aimed to describe the spatial organization of hoary foxes Lycalopex vetulus, and examine part of their interactions with sintopic canids, besides identifying threats to its survival. To contribute to the standardization of sampling strategies to monitor wildlife, capture technique was evaluated, and also trapping potential and success in monitoring canids through high frequency collars (VHF). We obtained 470 capture events using box traps baited with sardines. Of these, 347 (74%) corresponded to wild canids captures (mean success of 10.7 captures per 100 trap* night). Hoary foxes showed higher capture rates than other species, but were captured almost exclusively by medium-sized traps, while crab-eating foxes had high capture rates on medium- and large-sized traps. The maned wolf had high capture rates in large-sized traps. To allow additional monitoring of hoary foxes by camera trapping and register new individuals, we developed a technique to identify foxes through marks on the tail of these animals. During this study 73 wild canids were monitored by radio-collars and was possible to estimate that mean home range hoary foxes is 2.68 km2, of crab-eating fox 8.23 km2, and of maned wolves 66.54 km2. It is known that there is a wide variation in the social system of canids and that this is directly linked to how species are organized in space. The results presented reinforce that small South American Lupinae canids live in monogamous and territorial social systems. The three species were active mainly during the night and used up to 11 different types of shelters (n = 417 records). Yellow armadillo holes (Euphractus sexcinctus) were the most used shelter by the hoary fox while, while crab-eating foxes and maned wolves used more often clumps of tall grass. The main causes of canids deaths in the study area are result of human actions (41.3%) as road kill, domestic dog attacks, poisoning and shooting. Intraguild predation of smaller canids by pumas is the second most frequent cause of death. The third chapter also contains an assessment on the risk of extinction of the hoary fox, where after a wide review, the species was classified as vulnerable to extinction. In the Cerrado, a priority ecosystem for biodiversity conservation, landscapes altered by human action represent the current scenario. To better understand how species have been dealing with these changes it is urgent to increase studies in this direction.