Dados do Trabalho

TÍTULO

CAMERA TRAPPING AS A TOOL FOR DETECTING DISEASE IN WILDLIFE

Resumo

Camera traps have become ubiquitous in wildlife ecology research, being widely used to gather data on the abundance and habitat preferences of rare species. The ongoing modernization of camera traps allows for numerous applications, and several fields of research have arisen from camera trapping. However, could camera trapping also be a tool applied for disease detection in wildlife, as well as the study of possible transmission between species? In order to test this idea, we deployed 45 camera traps at two sites of Mirador State Park (the worldwide stronghold for the northern tiger cat): Mel and Cágados outposts. We laid out cameras so that all individuals of the target species (domestic dog, crab-eating fox, and northern tiger cat) within the study areas had a nonzero detection probability. In order to estimate the proportion of diseased animals we identified as many individuals as possible of domestic dogs, crab-eating foxes, and northern tiger cats. We checked for visual signs of disease and health condition: marks, scars, and overall body condition. To inspect the potential for disease transmission, we compared overlapping activity patterns between domestic dogs and the two wild carnivores, using the overlap package in R. Domestic dogs were detected at both study sites, we managed to identify 15 individuals at Mel and 7 at Cágados, with disease signs present in 20,0% and 28,6% of individuals respectively. We identified 12 crab-eating foxes at Mel and 21 at Cágados, of which 58,3% and 50,0% respectively had visible signs of disease. Foxes showed neat spots on their skin, clear visible signs of dermatophytosis, while domestic dogs showed non-specific signs, mainly very low body score. Activity overlap between domestic dogs and tiger cats was 57%, while that of domestic dogs and crab eating foxes was 79%. These numbers illustrate the potential for disease transmission between domestic and wild carnivores at the park, which represents a concern for the worldwide threatened northern tiger cat. This work has also shown the potential of camera trapping in assessing wildlife health condition, though it is worth noting that camera trapping alone cannot substitute laboratory analyses. Finally, the high prevalence of disease among domestic dogs and crab-eating foxes and the high activity overlap between domestic dogs and tiger cats represents a threat to the park’s tiger cat population. Thus, serious conservation actions will be required to safeguard the northern tiger cat in its key worldwide-protected area.

Palavras-chave

Northern savannas Brazil; Population assessment; Northern tiger cat; Domestic dogs; Crab-eating fox.

Financiamento

The Mohammed bin Zayed Species Conservation Fund