Rapid Urbanization of Red Foxes in Estonia: Distribution, Behaviour, Attacks on Domestic Animals, and Health-Risks Related to Zoonotic Diseases

Urban areas are becoming increasingly important for wildlife as diminishing natural habitats no longer represent a suitable environment for many species. Red foxes (Vulpes vulpes) are nowadays common in many cities worldwide, and in recent years they have colonized urban areas in Estonia. We used a public web-based questionnaire approach to evaluate the distribution and behaviour of Estonian urban foxes, to detect related problems and to assess health risks to humans and domestic animals. In total, 1205 responses were collected throughout the country. Foxes have colonized the majority of Estonian towns (33 out of 47) in a relatively short period of time, and have already established breeding dens in several towns. Despite their recent arrival, the behaviour of Estonian urban foxes is similar to that reported in longer-established urban fox populations: they are mostly active during night-time, often visit city centres and some also have dens in such locations. Certain characteristics of urban foxes serve as a basis for conflict with humans: foxes have entered houses and attacked domestic animals, killing cats and poultry. About 8% of reported foxes exhibited symptoms of sarcoptic mange, a disease that also infects domestic animals, especially dogs. The proportion of mange-infected foxes was higher in large urban areas. In addition to mange, a substantial fraction of red foxes in Estonia are known to be infected with the life-threatening tapeworm Echinococcus multilocularis, the causative agent of alveolar echinococcosis. Therefore, urban foxes may represent a source of serious infectious disease for pets and humans.