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Researchers believe they know the reason a pack of coyotes launched a rare fatal attack on a Canadian woman in 2009. Blame it on moose.

Coyote approaching a small child

Rare fatal coyote attacks

Coyote attacks against humans are rare. Fatal attacks are even rarer. In fact, only two fatal coyote attacks on humans have been confirmed to date. The first occurred on August 26, 1981. A coyote grabbed a three-year-old girl named Kelly Keen in the driveway of her father’s home in Glendale, California and dragged her across the road. Her father rescued her by chasing the animal away and rushed her to Adventist Health Medical Center, but she died in surgery due to blood loss and a broken neck.

The second fatal attack has long puzzled experts. On October 27, 2009, two eastern coyotes mauled a 19-year-old singer-songwriter named Taylor Mitchell at Cape Breton Highlands National Park in Nova Scotia. She was on a break from her concert tour when they stalked and chased her down the Skyline Trail. An air ambulance airlifted Taylor to Queen Elizabeth II Health Sciences Centre, but she died a few hours later after midnight from severe injuries and blood loss that were sustained during the attack. The attack was puzzling because the victim was an adult – much larger prey than coyotes would normally attack. Now, wildlife researchers have completed a study that may settle the question of why the coyotes launched an unprovoked fatal attack on the young woman.

Analysis of coyote diets and movements hints coyotes forced to prey on moose

By analyzing coyote diets and their movement in Cape Breton Highlands National Park, where the attack occurred on a popular trail, the researchers concluded that the coyotes were forced to rely on moose instead of smaller mammals for the bulk of their diet – and as a result of adapting to that unusually large food source, perceived a lone hiker as potential prey.

Coyote with a typical throat hold on a domestic sheep

The findings essentially ruled out the possibility that overexposure to people or attraction to human food could have been a factor in the attack – instead, heavy snowfall, high winds and extreme temperatures created conditions inhospitable to the small mammals that would normally make up most of their diet.

“The lines of evidence suggest that this was a resource-poor area with really extreme environments that forced these very adaptable animals to expand their behavior,” said lead author Stan Gehrt, a wildlife ecologist at The Ohio State University.

“We’re describing these animals expanding their niche to basically rely on moose. And we’re also taking a step forward and saying it’s not just scavenging that they were doing, but they were actually killing moose when they could. It’s hard for them to do that, but because they had very little if anything else to eat, that was their prey,” he said. “And that leads to conflicts with people that you wouldn’t normally see.”

The death of 19-year-old folk singer Taylor Mitchell is the only fatality resulting from a coyote attack on a human adult ever documented in North America.

Still, coyote attacks are extremely rare

Gehrt, who leads the Urban Coyote Research Project that has monitored coyotes living in Chicago since 2000, was consulted by media for his expertise after the attack. In urban areas like Chicago, where thousands of coyotes live among millions of people, injuries from coyote-human encounters are very rare.

“We had been telling communities and cities that the relative risk that coyotes pose is pretty low, and even when you do have a conflict where a person is bitten, it’s pretty minor,” said Gehrt, a professor in Ohio State’s School of Environment and Natural Resources. “The fatality was tragic, and completely off the charts. I was shocked by it – just absolutely shocked.

“A lot of people began wondering if we were at the front edge of a new trend, and if coyotes were changing their behavior. And we didn’t have good answers.”

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Gehrt expanded an initial investigation of the fatal attack – and a few dozen less severe human-coyote incidents in the park before and after Mitchell’s death – into a detailed field study. Between 2011 and 2013, he and colleagues captured 23 adult and juvenile coyotes living in the Cape Breton park and fitted them with devices to document their movement and use of space.

How coyote diet was analyzed

To obtain dietary information, the team also snipped whiskers from the live-captured coyotes and from the bodies of coyotes implicated in the fatal attack and in other human-coyote incidents. For comparison, the researchers collected fur from potential prey – southern red-backed voles, shrews, snowshoe hare, white-tailed deer and moose – and hair from local barbershops that served as a proxy for human food.

Coyote at Seedskadee National Wildlife Refuge carrying small prey

Seth Newsome, professor of biology at the University of New Mexico and corresponding author of the study, analyzed stable isotopes of carbon and nitrogen in these whisker and hair samples to determine what the coyotes had been eating in the months before they were captured or lethally removed from the population.

The analysis showed that, on average, moose constituted between half and two-thirds of the animals’ diets, followed by snowshoe hare, small mammals and deer.

“This dietary evidence was the critical piece to it,” Gehrt said. “Their diets changed because they’re taking advantage of whatever different food items are available at the time. We’re used to seeing big oscillations across the segments of whiskers depending on the season. But in this system, for these coyotes, we don’t see that – they flat line at the moose end, so there’s very little variation in their diet.”

Samples from the coyotes that were confirmed to have been involved in the fatal attack showed they had been eating only moose, “and their diet wasn’t changing,” he said. An analysis of coyote droppings confirmed the isotope findings. The researchers found only a few examples of individual animals having eaten human food.

Coyote movement shows they tend to avoid populated areas – if possible

Beyond the dietary analysis, Gehrt and colleagues did test for the possibility that coyotes were familiar with humans, and therefore not fearful around people. The movement patterns showed that while the coyotes’ space use was extensive – likely related to the need to search far and wide for prey – the animals largely avoided areas of the park frequented by people and were more active at night during periods when daytime human use was at its highest. Prohibition on hunting and trapping in the park also removed a human threat.

Coyote howling

“It’s a big area for these coyotes to live in and never have a negative experience with a human – if they have any experience at all,” Gehrt said. “That also leads to the logical assumption that we’re making, which is that it’s not hard for these animals to test to see whether or not people are a potential prey item.”

In cities and most other wilderness areas where coyotes live, food of all types is plentiful – suggesting only areas low on natural prey, like islands and remote northern climates, would pose a similar risk for coyote-human interactions, Gehrt said. Their survival in Cape Breton, he said, is attributable to their remarkable ability to adjust to their environment.

“These coyotes are doing what coyotes do, which is, when their first or second choice of prey isn’t available, they’re going to explore and experiment, and change their search range,” he said.

“They’re adaptable, and that is the key to their success.”

Image Credits

In-Article Image Credits

Coyote with a typical throat hold on a domestic sheep via Wikimedia Commons by US Department of Agriculture with usage type - Public Domain. January 2008
Coyote at Seedskadee National Wildlife Refuge carrying small prey via Wikimedia Commons by USFWS Mountain-Prairie with usage type - Creative Commons License. October 20, 2018
Coyote howling via Wikimedia Commons by USFWS Mountain-Prairie with usage type - Creative Commons License. October 19, 2011
Coyote approaching a small child via Wikimedia Commons with usage type - Creative Commons License. January 4, 2012

Featured Image Credit

Coyote approaching a small child via Wikimedia Commons with usage type - Creative Commons License. January 4, 2012

 

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