You may have noticed a common theme at the dinner table: Grandpa has spotted the fox in the yard again or perhaps your aunt has heard of a coyote in the local nature preserve. These discussions usually lead to a general wonder of whether wild canine populations are on the rise, if they are a positive or negative influence on the local environment and what their presence might mean for the neighborhood.
The Academy wanted to know these answers, too. So, we reached out to Dane Ward, PhD, assistant teaching professor in Drexel’s Biodiversity, Earth and Environmental Science (BEES) department who specializes in urban wildlife ecology, to learn more.
Are these wild canine populations rising, and if so, why?
DW: It’s actually quite hard for us to say if the populations of coyotes or foxes are increasing or rising. Both species tend to be crepuscular or nocturnal in urban habitats. From a scientific perspective, we have certainly observed that the public has gained an increased awareness of urban wildlife since the start of the pandemic. With folks working from home more often, and certain portions of cities seeing less human activity than pre-pandemic years, we have a scenario where urban wildlife might be more comfortable in certain areas with more human observers of wildlife. Even myself, as a wildlife biologist, have noticed during the pandemic that more squirrels, skunks and opossum are passing through my backyard than I previously expected. Much of this is due to my ability to observe my backyard habitat while being on Zoom meetings in my home office.
Can you tell us more about the relationship these canine populations have with humans?
DW: While we can’t be sure that either population has increased, we do know that both species are well adapted to living in the shadows of humans. In urban ecology we call species that thrive near humans as either ‘human-adapted’ or ‘human-exploiting’ species. Both coyotes and foxes are human adapted, meaning they receive indirect benefits from living near humans. More charismatic critters, like rabbits or Canada geese, might be human exploiters. Interestingly, human-adapted wildlife generally does not have antagonistic or negative interactions with humans, which is why they are able to maintain stable populations within urban landscapes and often go unnoticed.
All human-adapted urban wildlife is benefiting from our urban landscape. Perhaps because they can more easily find prey, since these species tend to be omnivorous, the urban landscape is great for them. They can hunt rodents and other small mammals (which we often see as pests), but they can also consume food waste by scavenging scrapes from trash or yards where folks feed their pets outdoors. To note, no one should be feeding their pets outdoors, as they almost certainly are creating a feeding station for myriad urban wildlife.
What about their relationships with other urban animal populations?
DW: The primary food source for foxes is small mammals, rodents, field mice and the like; foxes most certainly reduce rodent population sizes. Coyotes are really interesting; they have been documented to eat deer in early spring or early winter. Generally, they will eat young deer, or old and weak deer. Mostly, coyotes will scavenge roadkill or dead deer.
What is most interesting about coyotes is that their presence in the landscape actually changes deer behavior. So, with coyotes around, deer are generally more cautious and will tend to stay closer to more heavily wooded or vegetated areas, instead of foraying into folk’s yards.
Even more interesting is the relationship between coyotes and foxes. In certain landscapes, a lack of foxes has been documented to increase the incidence of Lyme Disease. Because mice are an integral part of the Lyme Disease transmission, when there are foxes, they eat the mice, thus reducing Lyme transmission. There are some cases where coyotes and foxes co-exist, the coyotes might out-compete foxes which means more rodents (coyotes don’t eat mice all that often, but foxes do) and this results in more Lyme Disease transmission.
What do we do if we spot one nearby?
DW: I think this question should be answered relative to one’s sense of acceptable risk and how well a person perceives their understanding of the animal being observed. For instance, if I see a fox hanging out near my yard and I’m near an urban green space or park I do not worry at all. That’s the fox’s habitat, and so long as it doesn’t behave abnormally or seems to have any mange, then life is good. However, if I observe a coyote in my backyard several times, and I am located in densely populated urban area with little green space, then I think I have an extenuating circumstance.
Both the coyote and fox can move pretty far distances each day and night, and do have site fidelity, meaning they know where particular features in the landscape are relative to their current location. If a coyote is making a stay in my backyard and I’m not near a park or green space (you can get an idea from Google Maps satellite view) then I would evaluate why my yard is attractive to the coyote, ameliorate or remove any attractants and call animal control to report the observations. Generally, there is probably no need to report a singular observation, especially if the animal sees you and takes off.
If you see a coyote or fox, however, who is actively acting atypical, like hanging around the same spot for a while and you see it in the middle of the day or it looks unhealthy, definitely call animal control or 911.
When we see a coyote or fox in our neighborhood, is that a positive sign of ecological health?
DW: Absolutely! Coyotes and foxes should be seen as an extension of our urban communities. While their presence does not necessarily indicate whether the ecosystem is healthy or not, it does fit a storyline across much of human history where canines have existed in rather close proximity to humans.
As a biologist, I am grateful to have coyotes and foxes within our human landscapes; they generally go unnoticed and are quite shy of human encounters. It’s a balancing act for these species. They exist in the human landscape but don’t really want to see us or interact with us directly.