The Fox and the Wolf: an Unlikely Duo
Scientists have found evidence that indicates that a resurgence of wolf populations in North America could be suppressing the dominance of coyote populations, allowing for red foxes to gain the upper hand in a long-observed rivalry.
According to a study published in the Journal of Animal Ecology, fur trapping records across North America indicate that red fox populations are on the rise where growing wolf populations are present.
For wolf-claimed regions such as Alaska, Yukon, Nova Scotia, and Maine, this data is demonstrating what researchers from the Oregon State University Department of Forest Ecosystems and Society are calling the "wolf effect."
The wolf effect shows how the presence and absence of wolves in a region can affect two other primary predators, coyotes and red foxes.
"As wolves were extirpated across the southern half of North America, coyotes dramatically expanded their range," research leader Thomas Newsome explained in a statement. "They were historically located in the middle and western United States, but they dispersed all the way to Alaska in the early 1900s and to New Brunswick and Maine by the 1970s."
This was bad news for red foxes, who could hunt and scavenge in peace in wolf territory, as the apex predators largely ignored their presence. Coyotes on the other hand, share more of the same prey as the red fox, and are far less tolerant of their presence. This resulted in an average three to one ratio, with coyotes heavily outnumbering red foxes.
However, according to Newsome and co-author William Ripple's work, the recent resurgence of wolf populations has resulted in a sudden tilt of the scales in favor of red foxes, resulting in fox populations outnumbering coyote populations four to one in regions reclaimed by wolves.
"This study gives us a whole other avenue to understand the ecological effects of wolves on landscapes and animal communities," Ripple said.
He adds that the strong correlation between fox and wolf populations cannot be ignored. It's not exactly a "friendly" agreement between the two predators, he explained. It is more-so just an ecological balancing act trying to reset to how things were more than a century ago.
Whether an ecology that has gone so long without high fox numbers can sustain this sudden population spike - not to mention a reintroduction of wolves - remains to be seen.