Calgary

Yes, Alberta does have native rats — and one man can't get rid of them

The rodents have caused thousands of dollars in damage by nesting in and under one Crowsnest Pass resident's property, leaving behind a skunky trail of destruction.

Experts say bushy-tailed woodrats are extremely smelly and attracted to shiny objects

Vern Emard says he's been battling invading, and very stinky bushy-tailed woodrats  on his property in southern Alberta Rockies since at least the 1990s.
Vern Emard says he's been battling invading — and very stinky — bushy-tailed woodrats on his property in the southern Alberta Rockies since at least the 1990s. (Submitted by Vern Emard)

Crowsnest Pass resident Vern Emard said pack rats, also known as bushy-tailed woodrats, have been scurrying around inside the walls of his homes and wreaking havoc on his property for more than two decades. 

The rodents have caused thousands of dollars in damage by nesting in and under his homes, leaving behind a skunky trail of destruction. 

"They like your bedding," he said. "They'll go right for your beds and they will [urinate] and [defecate], making a nest in your beds."

Emard says the pack rats destroyed a mobile home on his property in a remote mountain valley north of Blairmore, Alta.

"They chewed it so bad we couldn't salvage it," he said. "And because of the smell and the deprecation in the walls, we didn't want to."

Rats in Alberta

Alberta has been defending its borders against invasive rats for more than 70 years. Even pet rats are strictly forbidden.

However, bushy-tailed woodrats occur naturally in the Rocky Mountains and southern parts of the province, according to Alberta's rat control program. 

Ord's kangaroo rats, an endangered species, are also found in the province, in a small area near Medicine Hat, according to Environment Canada.

WATCH | The history of Alberta's rodent enemy: 

How Alberta keeps rats out

57 years ago
Duration 1:41
The province maintains its rodent-free status in 1968 by employing 250 pest control officers.

Emard built his next mobile home on cement to block the invading woodrats from tunnelling in. But eventually, they found a way to dig underneath the structure. 

He thinks the critters are attracted to the heat, and says they're smarter and harder to kill than many household pests. 

"A mousetrap or rat trap rarely can catch a pack rat," he said. "They'll take the bait, they'll spring the trap, and then they'll just laugh at you."

Stinky, crystallized rat urine offers a window to the past

Scottie Potter, with the Alberta Institute for Wildlife Conservation, says pack rats create overwhelming odours by peeing on their nests to make them more durable. 

"They are famously quite smelly," she said. "From personal experience,… you [can] smell them from a good three metres away. More than that really." 

Pack rat nests, or middens, offer important research opportunities, said Potter, for those who brave the stench. 

This baby woodrat 'hitched' a ride on a vehicle returning to Calgary from the mountains and is now in the care of the Alberta Institute for Wildlife Conservation. The plan is to release the rodent back in its natural environment later this summer, the institute said on Monday, July 17, 2017.
The Alberta Institute for Wildlife Conservation cared for an orphaned baby pack rat in 2017, eventually releasing it back into the wild. (Alberta Institute for Wildlife Conservation)

When built in caves or dry locations, they can survive for tens of thousands of years, according to the North American Packrat Midden Database

Scientists have extracted ancient insect DNA, and mummified plant and animal remains from middens around North America.  

"These pack rats can tell us a whole lot about the climatic changes, what to expect from vegetation, what to expect from animals as well," said Potter. "It's probably the most important thing about them."

Home infestations very rare

Jun Bukht, an entomologist with Major Pest Control, says pack rat infestations are very rare, and he's never seen one in over 12 years spent working with pests. 

But the animals are attracted to shiny objects, like car keys or jewelry, which can occasionally draw them into vehicles or buildings, he said.

"They're not dangerous like other rats.… They're mostly outside," said Bukht. "However, if they get into the house, they can do electrical damages and damages to the structure itself."

Alberta's rat control program receives about one phone call a month about woodrats.  

A rat poster in Alberta
Poster released by the Alberta Department of Public Health circa 1948 (A17202b/ Provincial Archives of Alberta) (A17202b/Provincial Archives of Alberta)

"What usually happens is people spend a lot of time in the foothills of Alberta," said Karen Wickerson, Alberta's rat and pest specialist. 

"Bushy-tailed woodrats quite often hitch rides on the vehicles. And [people] bring them back to an urban centre and they find that something has taken up residence in their garage." 

Pack rats are designated a nuisance animal in Alberta, which means people can trap and kill them on their properties, said Wickerson. 

After spending time in the mountains, she recommends inspecting under vehicle hoods and checking trailers for holes to keep unwanted hitchhikers from tagging along. 

Emard said he harbours no ill will toward the bushy-tailed woodrats, and enjoys seeing wildlife around his property.  

"It's just part of rural life.… I've lived with mice my whole life too," said Emard. "They're actually a very cute critter, and they could probably be sold in a pet store if they didn't stink so bad."

ABOUT THE AUTHOR

Brendan Coulter is a reporter for CBC Calgary. He previously served as CBC British Columbia's Kootenay pop-up bureau reporter. He has also worked for the CBC in Kamloops and Edmonton. Reach him at brendan.coulter@cbc.ca.