Picture a healthy forest that serves as home to a diverse range of species: Birds are fluttering among the tree branches, salamanders are slithering through the leaf litter, and wolves are tracing the scent of deer in the understory. Each of these animals has a particular role, and most ecologists would contend that the loss of any one of these species would be detrimental to the overall ecosystem.
Regrettably, whether due to [reasons not specified], [reasons not specified] or [reasons not specified], [species disappearance details not provided]. Meanwhile, other species have [arrival or change details not provided].
[Author’s statement], I’m intrigued by what these alterations signify for ecosystems – can these newly arrived species functionally substitute the species that were previously present? I examined this process in eastern North America, where some top predators have vanished and a new predator has emerged.
A primer on predators
Wolves once roamed across every state east of the Mississippi River. However, as the land was developed, many people regarded wolves as threats and [actions not specified]. Currently, a combination of [wolf types not specified] and [wolf types not specified] persists in Canada and around the Great Lakes, which I collectively refer to as northeastern wolves. There is also a small population of red wolves – [details not provided] – on the coast of North Carolina.
The disappearance of wolves might have provided coyotes with the opportunity they required. Starting around 1900, coyotes began [expansion details not provided] and have now colonized almost all of eastern North America.
<
So, are coyotes the new wolves? Can they fulfill the same ecological role that wolves used to? These are the questions I aimed to answer in my paper published in August 2025 in the [journal name not provided]. I focused on their role as predators – what they consume and how frequently they kill large herbivores, such as deer and moose.
What’s on the menu?
I began by reviewing every paper I could locate on wolf or coyote diets, recording what percentage of scat or stomach samples contained common food items like deer, rabbits, small rodents or fruit. I compared northeastern wolf diets to northeastern coyote diets and red wolf diets to southeastern coyote diets.
I discovered two notable differences between wolf and coyote diets. First, wolves ate more medium-sized herbivores. Specifically, they consumed more beavers in the northeast and more nutria in the southeast. Both of these species are large aquatic rodents that impact ecosystems – [beaver ecosystem impact not specified], sometimes unfavorably for landowners, while nutria are non-native and [nutria details not provided].
Second, wolves have a more restricted diet overall. They eat less fruit and fewer omnivores such as birds, raccoons and foxes compared to coyotes. This implies that coyotes are likely performing some ecological functions that wolves never did, such as dispersing fruit seeds in their feces and suppressing populations of smaller predators.
<
Killing deer and moose
But diet studies alone cannot provide the full picture – it’s usually impossible to determine whether coyotes killed or scavenged the deer they ate, for instance. So, I also reviewed every study I could find on [deer or moose] mortality – these are studies that tag deer or moose, track their survival, and assign a cause of death if they die.
These studies uncovered other significant differences between wolves and coyotes. For example, wolves were responsible for a substantial proportion of moose deaths – [19% of adults and 40% of calves], while none of the studies documented coyotes killing moose. This means that all, or nearly all, of the moose in coyote diets is scavenged.
Coyotes are proficient predators of deer, though. In the northeast, they killed more white-tailed deer fawns than wolves did, [28% compared to 15%], and a similar proportion of adult deer, [18% compared to 22%]. In the southeast, coyotes killed [40% of fawns but only 6% of adults].
Rarely killing adult deer in the southeast could have implications for other members of the [ecosystem not specified]. For example, after killing an adult ungulate, many large predators leave some of the carcass behind, which can be [beneficial details not provided]. Although there is no data on how often red wolves kill adult deer, it is likely that coyotes are not supplying food to scavengers to the same degree that red wolves do.
Are coyotes the new wolves?
So, what does all this mean? It means that although coyotes eat some of the same foods, they cannot completely replace wolves. Differences between wolves and coyotes were particularly evident in the northeast, where coyotes [relationship with beavers not specified] or beavers. Coyotes in the southeast were more similar to red wolves, but coyotes likely killed fewer nutria and adult deer.
The return of wolves could be a [benefit not specified] for regions where wildlife managers wish to reduce moose, beaver, nutria or deer populations.
Yet even with the [recovery details not provided], wolves will probably never fully regain their former range in eastern North America – there are too many people. Coyotes, on the other hand, [status not specified]. So, even if wolves never fully recover, at least coyotes will be in those areas partially fulfilling the role that wolves once had.
Indeed, humans have changed the world so much that it [comparison not specified] to the way things were before people significantly altered the planet. While some restoration will surely be possible, researchers can [investigate details not specified] the extent to which new species can functionally replace missing species.
, Postdoctoral Associate – Wildlife Ecology,
This article is republished from under a Creative Commons license. Read the.
