Potential risks to human and animal health rise when people experiencing homelessness are forced to seek shelter in the same secluded, inner-city landscapes as urban coyotes, a new study cautions.

The research, published in Frontiers in Ecology and the Environment, a peer-reviewed scientific journal, is the first study to examine the relationship between homeless encampments and urban coyotes. It used Edmonton’s river valley as a case study for these close encounters. 

The study from the Edmonton Urban Coyote Project — a collaborative research initiative led by the University of Alberta — found that unhoused people and coyotes often live in close proximity.

The competition for space and resources creates a potentially dangerous dynamic, increasing the risk of human-coyote conflict and the spread of infectious diseases from animals to people. 

A losing equation

“This is a lose-lose-lose situation,” said Sage Raymond, a University of Alberta researcher who was the study’s lead author.

“We’ve got coyotes accessing food and encampments, which is not good for them, and we’ve got people being exposed to potential disease agents.”

Raymond believes the dynamic is also unfolding in other North American cities where extreme poverty and urban coyotes co-exist.

The number of people without access to shelter and incidents of human-coyote conflict are both rising, Raymond said. Yet, that co-existence remains largely unexplored by researchers, she said.

The study found that people sleeping rough near coyote dens face an increased risk of dangerous encounters with those animals. They also have a higher risk of contracting infectious diseases, including a parasite currently proliferating through Alberta’s coyote packs.

Coyotes living near encampments, meanwhile, could get displaced or habituate to human food, raising the probability of them growing aggressive and becoming a nuisance to nearby neighbourhoods.

Raymond said the study’s findings should not instigate further crackdowns on homeless people nor urban coyote culls.

Instead, she said, there needs to be more targeted conservation efforts, along with awareness campaigns and improved accessible medical care among vulnerable populations.

The study relied on 15 years of research by the Edmonton Urban Coyote Project, which has monitored the city’s coyote population since 2009.

According to the project, as many as 3,000 coyotes are in Edmonton. The urban packs rely on the city’s North Saskatchewan River valley as a key habitat — the same expansive parkland where thousands of homeless encampments are erected each year. 

Estimates by Homeward Trust suggest there are as many as 5,000 unhoused people in Edmonton, and 1,000 — one fifth — sleep rough every night. Municipal government reports say the City of Edmonton cleared more than 5,600 encampments last year.

Colleen Cassady St. Clair, a wildlife biologist who leads the coyote research project, said the overlap has been evident in their fieldwork for decades and prompted work on the encampment study.

She and her research team frequently encountered encampments while searching for sites to live-trap or collar coyotes, or monitor their dens.

St. Clair recalled seeing a coyote den constructed beneath an abandoned shopping cart and dens dug out from sleeping ledges people carved out of the steep river bank. Trail cameras deployed at coyote dens have captured people building their homes out of tarps and blankets. 

During fieldwork for a 2023 study, which saw them track 120 dens in Edmonton, St. Clair’s team came across 73 vacant encampments.

She said they will often find telltale signs that coyotes had fed on garbage and debris left behind, including coyote tracks in the snow and their distinct teeth marks on discarded bedding and garbage.

“The things that people would seek, if they were in that circumstance of needing shelter outdoors, and the things that coyotes would seek are actually really similar,” she said, noting that both tend to seek out densely forested areas, far from traffic, trails and people.

“Both coyotes and people are looking for places that are secure enough that they can let their guard down.” 

But encampments are an ecological danger, because they attract coyotes, giving them easy access to human food and making them less wary of people, St. Clair said.

The study also raises the concern of people’s exposure to diseases carried by coyotes, particularly alveolar echinococcosis, a parasitic infection spread through a tapeworm, which has been found in more than half of Edmonton’s coyotes. 

The tapeworm’s microscopic eggs, known as Echinococcus multilocularis, are shed in coyote feces — which, field research shows, are heavily concentrated near encampments.

According to the study, the parasite spreads through contact with coyote scat, so people living outdoors face severe exposure risk, which is exacerbated by less access to hygiene facilities and a higher prevalence of immunocompromised individuals.

‘A hotspot’ for infection

Darcy Visscher, a biologist and Canada Research Chair in urban ecology, agrees that Edmonton’s unhoused population faces a heightened risk, noting the infection is considered 90 per cent fatal in humans.

The parasite’s larvae form tumor-like masses that primarily invade the liver, laying dormant for five to 15 years before severe symptoms surface.

The tapeworm strain was first detected in Western Canada in 2012. Since then, cases have surged, with more than 50 recorded in Alberta, including 20 in the Edmonton region, he said.

“Within the North American context, Alberta is a hotspot,” Visscher said. 

We just hope to raise awareness that a vulnerable population of people might be even more vulnerable than we realized.– Colleen Cassidy St. Clair

Visscher hopes the study will prompt an examination of local infection rates and improved outreach with frontline agencies.

When asked what measures are being taken to track or limit the parasite’s spread in the province, officials with Primary and Preventative Health Services said Alveolar Echinococcosis is under laboratory surveillance, meaning only laboratory-confirmed cases are reported to provincial health officials.

Typically, “only one or a few cases” are recorded each year and public health case investigation is not conducted for every case. Therefore, risk factor data, such as housing status, are not collected, the ministry said.

The study calls for health-care programs to better diagnose infectious diseases, hygiene supplies for encampments, and education on safe “hazing” techniques to restore coyotes’ natural wariness.

Although, St. Clair said the ultimate solution remains giving everyone access to secure housing.

“We just hope to raise awareness that a vulnerable population of people might be even more vulnerable than we realized,” she said. 

In a statement to CBC News, officials with Alberta’s Ministry of Mental Health and Addiction said encampments pose “several dangerous risks” to their residents and the province continues to work closely with the City of Edmonton, community organizations and frontline partners to help vulnerable Albertans connect with housing and supports.

Dr. Louis Francescutti, an emergency room physician and longtime advocate for Edmonton’s unhoused populations, said the study is further evidence of Alberta’s homelessness crisis and its potential consequences.

Infectious disease is just one of the myriad harms to which people living on the street face, he said.

“The focus should not be on better medical treatment; the focus should be on, ‘Why are people living in encampments in the first place?’” he said.