First, some terminology.
Some wild animals are labeled ‘synanthropic species’. These species live near humans and directly benefit from human-altered environments like gardens, garbage dumps, and farms. Such areas provide critical resources such as cover (think sheds, under porches, barns), and food (for example, bird feeders, our garbage, the rodents attracted to our garbage, and non-native garden plants that provide fruit year round). Examples of synanthropic species are raccoons, skunks, foxes, coyotes, and certain rodents. These species have learned how to exploit human-created habitats, and they thrive in a mosaic of suburbs and cities next to woodlots and fields, which provides some distance from humans, but also the close proximity that benefits them as well.
The red fox is also known as an ‘edge species’, which means they naturally occur at the borders between two habitat types, which is called an 'ecotone'. These ecotones, such as woodlands transitioning into grasslands, offer them different resources that they need to survive, which is why red foxes do not select just woodlands as their habitat. Water sources and corridors, like creeks, are also important in habitat selection. Den sites are usually found within at least 1 to 2 miles of a water source. As we will see below, humans have created habitats very similar (gardens and yards that back up to brushy or densely forested areas as an example) to their natural habitat; our human-modified environments mimic the transition zones of these selected habitats.
Why aren't red foxes true forest species and why do they prefer a transitional zone of two habitats?
As mentioned earlier, it’s a common misconception that the reason we see an influx of foxes and coyotes in our suburbs and cities is because we have supplanted their woodland homes with our development. Although habitat loss for some species is a real issue that has forced animals from their territories, synanthropic species, like the red fox, are seldom true forest animals by nature, but rather “edge species”. But why? With red foxes it has a lot to do with their primary prey.
Red foxes are opportunistic omnivores but they are primarily hunters of rodents, such as mice and voles, which live in grassy fields. In addition, insects, rabbits, hare, and birds also make up their menu; these species tend to favor the shrubby and weedy edges between forest and fields. However, red foxes also require cover and den sites that may not be available in open areas. Forests, with dense brush at its edge and hollow logs offer possible den sites and shelter. Therefore, where forest meets grassland is the ideal natural environment for the red fox. Similarly, a neighborhood with human shelters, creeks and ponds, corridors (like a road, railroad or ditches) they can travel to get from one habitat patch to another, lawns, fields of grass meeting the edge of a fragmented forested area or green space, basically provides the same resources that a natural ecocene of forest and grassland provides. And they have an added bonus of even more food resources by staying close to humans: our food waste and the rodents it attracts.
So what does all this have to do with why they are in my town?
The conclusion is that through our own expansion, city developments, and agricultural practices we have created an induced ecotone that mimics in many ways the natural ecotones where red foxes are found naturally in the wild. Human-modified areas often provide a mosaic of habitats: grass and fields where they can hunt, ditches, parks with trees and fragmented woodlands that provide cover and safety, corridors, and even denning opportunities in our green spaces and sometimes under our sheds and houses (Note: it is thought that Red Foxes may prefer a more natural setting away from high human traffic for dens, unless the lack of resources or green space is high, then they will be more likely to den under/in human infrastructure). And of course as mentioned previously, don't forget that living among humans, or in close proximity to humans, means even more food resources via our trash and the rodents drawn to it.
It's no wonder the red fox is drawn to such human-disturbed areas. And, it's no wonder they are here to stay.
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