Evaluating the function of wildcat faecal marks in relation to the defence of favourable hunting areas

Abstract

To date, there have been no studies of carnivores that have been specifically designed to examine the function of scent marks in trophic resource defence, although several chemical communication studies have discussed other functions of these marks. The aim of this study was to test the hypothesis that faecal marks deposited by wildcats (Felis silvestris) serve to defend their primary trophic resource, small mammals. Field data were collected over a 2-year period in a protected area in northwestern Spain. To determine the small mammal abundance in different habitat types, a seasonal live trapping campaign was undertaken in deciduous forests, mature pine forests and scrublands. In each habitat, we trapped in three widely separated Universal Transverse Mercator (UTM) cells. At the same time that the trapping was being performed, transects were conducted on foot along forest roads in each trapping cell and in one adjacent cell to detect fresh wildcat scats that did or did not have a scent-marking function. A scat was considered to have a presumed marking function when it was located on a conspicuous substrate, above ground level, at a crossroad or in a latrine. The number of faecal marks and the small mammal abundance varied by habitat type but not by seasons. The results of the analysis of covariance (ANCOVA) indicated that small mammal abundance and habitat type were the factors that explained the largest degrees of variation in the faecal marking index (number of faecal marks in each cell/number of kilometres surveyed in each cell). This result suggests that wildcats defended favourable hunting areas. They mark most often where their main prey lives and so where they spend the most time hunting (in areas where their main prey is more abundant). This practice would allow wildcats to protect their main trophic resource and would reduce intraspecific trophic competition.

Key Words:

• defence
• faecal marking behaviour
• small mammal abundance
• trophic
• resource
• wildcat

ACKNOWLEDGEMENTS

We would like to thank the Nature Conservation Service of Ourense (Regional Government of Galicia) for providing the permits required to conduct this study in the Montes do Invernadeiro Natural Park, with particular thanks to Víctor Manuel Gil. We are especially indebted to Dr F. Palacios, who kindly provided us with the small mammal traps. We thank A. Gago for his assistance in the analysis of the field data. We are grateful to gamekeepers Ricardo Prieto, Tomás Pérez, Paco Barja, and Antonino Núñez, who kindly provided us with logistical assistance during the fieldwork.