Coyote populations across the United States are influenced by a number of factors, but surprisingly their abundance is found to be higher in areas that allow hunting of the predator, according to research by a University of Utah wildlife biologist and colleagues in other states.

As U.S. landscapes became increasingly plowed and paved over the past couple centuries, wildlife has become less abundant thanks to the loss and fragmentation of habitat. But not coyotes, North America’s most successful mid-sized predator, which have expanded their range despite eradication campaigns and rapid urbanization.

Coyotes are bold generalists, eating anything from seeds, trash, roadkill, rodents, deer fawn, even pets, and fill niches left vacant by the elimination of bears, wolves and cougars, according to co-author Austin Green, a researcher with the U’s Science Research Initiative and former graduate student in the School of Biological Sciences.

It is reasonable to expect hunting to reduce species abundance, especially in conjunction with other anthropogenic factors that spurred the wave of Holocene extinctions. Unregulated hunting, after all, resulted in the disappearance of the passenger pigeon, dodo and monk seal, and near-extinctions of many other now-rare species, including iconic megafauna such as the American bison and white rhinoceros.

Coyotes, on the other hand, have displayed a pronounced resiliency in regions, such as Utah where hunting and trapping these predators is heavily subsidized and barely regulated, according to the findings based on extensive camera surveys.

“This is corroborating a lot of other evidence that direct hunting and intervention is actually not a really good way to manage coyote populations, if the goal is to decrease their abundance,” Green said.

The new study, which was funded in part by the U’s Global Change and Sustainability Center, was led by the University of New Hampshire (UNH). It relied on data compiled by Snapshot USA, a sprawling collaborative campaign to sample wild mammal populations with motion-triggered trap cameras arrayed in transects each fall.

“The impressive Snapshot USA project provides a yearly glimpse into our nation’s wildlife thanks to hundreds of researchers and the coordination by the Smithsonian and the North Carolina Museum of Natural Sciences,” said lead author Remington Moll, an assistant professor in UNH’s Department of Natural Resources and Environment in a university press release. “By combining data from cameras with satellite-derived habitat metrics and advanced statistical models, we got an unprecedented look into continent-scale trends for this fascinating species.”

Green, Moll and their research partners conducted a three-year study using cameras to assess critical factors for coyote abundance. Nearly 4,600 camera trap sites arranged in 254 arrays were deployed across the contiguous United States. Six arrays were in Utah, including the four Green maintains near Salt Lake City in the Wasatch Mountains and along the Jordan River. The sites included upper City Creek and Red Butte canyons.Two other arrays were deployed  near St. George by biologists at Utah Tech University.

Each array covered a transect 10 to 15 kilometers long with a camera placed every 500 meters, usually affixed to a tree about 20 inches off the ground, with 15 to 20 cameras per transect.

“It’s literally a snapshot into wildlife behavior before they either do their migration or bears go into the den,” said Green, who also works as a conservation ecologist with the Utah-based nonprofit Sageland Collaborative. “It’s a look in this small window where if we repeat it time and time again, year after, we can get really good information about how things are changing over time.”

Snapshot USA has compiled photographic wildlife data every fall for the past seven years and is expected to release an updated dataset through 2024.

For the coyote study, observations were recorded during the fall months of 2019 to 2021, and then statistically analyzed, with 22 separate factors, or covariates, considered. These included: urban development, biome type (e.g. forest, grassland), biome edge (e.g. forest-shrub edge), presence of food sources (e.g. small prey, soft mast), an abundance of competing species (e.g. black bears, pumas), coyote colonization period, location (latitude and longitude) and coyote hunting.

After analyzing more than 3,100 coyote detections across the camera trap network, the researchers modeled their significant observations in relation to their chosen covariates at 100-meter and 5-kilometer scales. The findings detected strong negative abundances for urban development, colonization time and latitude. Conversely, coyote abundance is more positively associated with separate biome covers, and in regions with coyote hunting. The 97% positive abundance for hunting at a 100-meter scale heavily implies that coyotes thrive in the face of hunting pressure.

“Because they’re such territorial animals that if you remove the most territorial one,” Green said, “two or three take their place, start breeding, and you lead to actual increases in coyote population.”

These findings come in stark contrast to the effects of hunting on other carnivore populations, such as wolves, cougars and other big cats, which have been extirpated from most of their native ranges. Regulations for coyote hunting are far looser than for other wildlife species, often bearing no seasonal restrictions, bag limits nor even a license requirement. In Utah, several thousand coyotes are killed every year under a bounty program authorized by the Legislature in 2012 that pays members of the public $50 for a set of ears.

The researchers hypothesize that hunting lowers the average age of coyotes, leading to less competition for food, which increases litter sizes. Coyotes also demonstrate a keen ability to find food sources and naturally roam in search of new territories, traits that enable populations to rebound in places where they have been eliminated.

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Published in the January edition of the journal Ecography, the paper “People or predators? Comparing habitat‐dependent effects of hunting and large carnivores on the abundance of North America’s top mesocarnivore” was co-authored by Remington Moll of the University of New Hampshire; Roland Kays of North Carolina State University; and Maximilian Allen of the University of Illinois. Funding came from the USDA National Institute of Food and Agriculture and the state of New Hampshire, with additional support from the Illinois Natural History Survey, the University of Illinois, the Global Change and Sustainability Center at the University of Utah, Sageland Collaborative and the National Science Foundation.

• Brian Maffly Science writer, University of Utah Communications
  801-573-2382 brian.maffly@utah.edu