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.
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.
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.
“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.”