We aimed to compare body condition, urine profiles, and survival times between red foxes (Vulpes vulpes) that were infected with sarcoptic mange and others that were uninfected. First we compared the relative body mass, chest girth, fat reserves, and urinary urea nitrogen:creatinine (UN:C) ratios of red foxes in three infection classes: uninfected, class I (no hyperkeratotic mange), and class II (hyperkeratotic mange present). Infected foxes had lower relative body mass and lower fat reserves than uninfected foxes. Both fat reserves and urinary UN:C data suggested that class II infection was more severe than class I infection. Urinary UN:C in class II foxes was significantly higher than in uninfected and class I foxes, indicating accelerated muscle catabolism in class II foxes. Elevated urinary UN:C has never been recorded in wild canids, indicating that these animals had been subjected to a period of prolonged starvation or chronic undernourishment. We also estimated the survival time of foxes once infected with mange from capture–mark–recapture data. Twenty-five foxes were caught at an early stage of infection and had a known date of death. Although some were treated once with ivermectin they did not recover, and their survival time was no longer than that of untreated infected foxes. Untreated infected adults survived for up to 271 days after capture, which is longer than previously suggested. Overall, the survival time of infected foxes was roughly one-fifth of that of uninfected foxes (matched by age and sex).

S. 2003. Changes in red fox habitat preference and rest site fidelity following a disease-induced population decline. Acta Theriologica 48: 79-91.The habitat preferences of red foxes Vulpes vulpes (Linnaeus, 1758) in Bristol, UK, were compared during periods of high and low population density following an outbreak of sarcoptic mange (Sarcoptes scabiei). These periods are termed 'pre-epizootic' and 'post-epizootic', respectively. Habitat preferences were compared between periods during nocturnal activity and diurnal inactivity using compositional analysis. Back gardens were the most preferred habitat for pre-epizootic foxes during periods of activity; back gardens and allotment/woodland habitats were equally preferred by post-epizootic foxes, with a trend for allotment/woodland to be the most favoured. During periods of inactivity, pre-epizootic foxes selected back gardens for diurnal rest sites, compared with allotments/woodland in the post-epizootic period. Post-epizootic foxes also showed a significant decrease in rest site fidelity, such that they were very unlikely to re-use a rest site more than once. In comparison, pre-epizootic foxes were often very faithful to one or a small number of sites. Such changes in habitat preference and rest site fidelity could have been facilitated by: (1) changes in food availability, (2) a decrease in intra-specific competition, (3) the requirements of defending larger territories post-epizootic, or (4) an avoidance of habitats that might increase the likelihood of mange transmission. The management implications of these results are discussed.

No abstract

No abstract