Aargau sees more urban foxes as animals adapt to city life

More residents in the Swiss canton of Aargau are reporting foxes in built-up areas, SRF reported. Experts say urban foxes now live differently from foxes in the countryside and may no longer regularly mix with them.

The municipalities of Würenlos, Birmenstorf and Windisch have warned residents not to put rubbish bags outside too early and not to feed the animals. Feeding can increase the risk of foxes transmitting diseases to one another, said Reto Fischer, a hunting specialist at the Aargau forestry department.

Urban foxes have developed different social behaviour, according to Sabine Kleppeck, co-head of urban development and the environment for the city of Baden. They form a kind of clan led by a female and a male. Young foxes stay for more than a year, and only the dominant pair reproduces while the others help raise the young.

Kleppeck said urban foxes also have smaller brains and shorter snouts than rural foxes because they rarely need to hunt for prey in the ground. Their fur is often spotted or striped, as they have less need for camouflage. The animals increasingly rely on waste from settlements instead of hunting.

These findings are based mainly on research from London. A study comparing fox skulls from urban and rural areas in the early 1970s found that city foxes had shorter, stronger snouts and smaller braincases, features that could reflect adaptation to easily available food such as rubbish and leftovers, said Fabio Bontadina of the Swild research organisation.

However, the London study is the only major study of its kind, and reports of short-snouted foxes in Switzerland remain anecdotal. Further research is needed. Kleppeck also said residents must consider how they handle rubbish and food waste to prevent urban fox populations from growing too large.