Genetic structure and dispersal of red foxes (Vulpes vulpes) in urban Melbourne

This study sought to investigate the potential for gene flow and dispersal between three sampled populations of urban Melbourne foxes (Vulpes vulpes). Five highly polymorphic canine microsatellites were used to investigate the population structure of foxes. The dispersal of 14 foxes, captured and radio-collared as cubs, were monitored periodically over two years. Dispersal estimates for males and females were also calculated from published regression equations that related social group density to dispersal distance. Genetic differentiation between urban populations was greater than between more widely spaced rural populations and was also greater than that found between San Remo and Phillip Island populations, which are separated by a water barrier. A deficiency of heterozygotes was detected in the total Melbourne population, but not at any of the field sites. Mean dispersal distances after 24 months (male = 3.5 km, female = 2.0 km) compared well with published accounts of dispersal in British cities. Dispersal distance estimates for female foxes from all sites were lower than straight-line distance for all but one site. Both the genetic and ecological data suggest a restricted ability for foxes to disperse between sites within urban Melbourne.