Living Door To Door With Foxes: How Urbanization Affects Wildlife
Image Courtesy: RTE
Have you encountered any foxes in your neighbourhood recently? Assumed to have first moved into London in the 1930s, red foxes (Vulpes vulpes) can now be found in almost every UK town. In fact, a 2013 report by the Department for Environment, Food and Rural Affairs estimates that there are roughly 430,000 foxes in the UK and as many as 150,000 could be city dwellers. And they have a reputation.
In 2011, a fox moved into the 72nd floor of the Shard skyscraper as it was under construction and survived entirely on food scraps left by workers. Three years ago, the country cheered as Chief Mouser Larry (the cat) was caught on camera chasing off a curious fox from No 10. London’s foxes are known to be mischievous and daring, willing to eat whatever they can get a hold of, and seemingly unbothered by humans.
In comparison, rural foxes are skittish and shy. Rarely seen near humans, they are hunters, feeding on rodents and birds as well as a selection of fruit and vegetables.
Some believe that cities have made foxes more sly. It seems reasonable that the proximity to humans, opportunities for scavenging, and complexity, if not danger, of the urban environment could have favoured bolder and smarter individuals. However, a study published in 2023 seems to disprove this idea. By setting up puzzles for foxes to solve for food in 104 locations across the country, researchers attempted to assess foxes’ daring and intelligence. They found that while urban foxes were indeed more likely to approach the puzzle, they were not any more likely to solve it.
Indeed, findings from recent years suggest that urban foxes’ brain capacity has shrunk. In 2020 researchers analysed 111 skulls of London foxes and found that there were significant differences in their shape compared to countryside foxes. According to the findings, urban foxes have shorter and wider snouts with smaller braincases. They also found male and female foxes’ skulls differed less among urban populations. These changes, so the paper states, mirror the structural changes that occur with domestication.
“Domestication syndrome”, first introduced by Charles Darwin, describes a phenomenon in which domesticated animals seem to have a set of traits not found in their wild counterparts. It appears that animals that live with humans, do not only look “cuter” (think floppy ears and curly tails) but are also less fearful of humans and more willing to engage in social interactions. One hypothesis for why this happens is that these traits are genetically linked through embryonic stem cells called “neural crest cells”. When humans select animals based on how easy they are to get along with, other physical features may come along with that trait.
Though urbanization evidently has a significant impact on city foxes, they appear to be thriving despite it all – even looking a little scrawnier than their rural cousins. Unfortunately, however, not all animals fare so well under human influence.
Continuously expanding cities mean many natural habitats are becoming smaller and fragmented. Urban environments are unique in their increased noise and light pollution, as well as available food sources. This in turn affects wildlife’s diets, circadian rhythms, reproductive behaviours, as well as the dynamic between predator and prey animals. Many animals cannot cope with the conditions of our cities. In particular, larger-bodied animals like deer and elks or larger predators like cougars have a hard time adapting to the challenges of urban life. For them, entering urban areas often leads to conflict with humans. Reports of wildlife-vehicle collisions, property damage, and attacks to people are increasing globally. It is estimated that by 2100 urban expansion will lead to 11-33 million hectares of natural habitat loss. With urban environments accommodating only a fraction of native species, we are bound to experience a profound loss of biodiversity.
Fortunately, there is hope yet. Maintaining green spaces and wildlife corridors have been shown to help animals to adapt to cities and allow them to move between habitats. Some cities are now also encouraging wildlife-friendly home construction. By involving ecologists early on in urban planning projects, wildlife-inclusive urban design could go a long way to enable environments where humans and animals both can thrive.