Rattlesnake health? No great shakes
THREATENED: Researchers fear encroaching development hampering conditions for Okanagan’s rattlers
Rattlesnake country can be a treacherous place, even if you’re a rattlesnake.
As the hot desert sun beats down and folks flock toward the south Okanagan’s myriad wineries and resorts, the Northern Pacific rattlesnakes slither toward refuge, away from the threat of frightened and curious humans.
The snakes are listed as “threatened” federally and blue-listed provincially — which means it’s illegal to harm, kill or capture them — but researchers continue their mission to determine how to ensure the population doesn’t dwindle as humans move in on their turf.
Emily Lomas, a researcher based in Kamloops, recently investigated the effects of human disturbance and habitat development on a population of rattlesnakes in B.C.
After examining the length and weight of hundreds of snakes, her team found that those using “disturbed sites” had significantly lower body condition than those in areas left alone by humans.
Lomas said more research is needed to determine what’s causing the snakes’ diminished condition but she offered some explanations.
“It could be that the food is lower quality or that there isn’t as much of it in these disturbed sites. It could be that the places they lived in caused more stress and that’s causing a physiological response for them.”
Lomas is concerned the affected rattlesnake population will have difficulty recovering, in part because females take several years to mature, mate only every two or three years and have small litters.
“Just the death of one or two mature females in a population can have quite a big impact,” she said.
“The destruction of an entire den or hibernaculum would be pretty devastating to a population, especially if it was a fairly active den.
“I think it’s concerning that they’re potentially not doing that great, because snakes need to have good body condition to survive the winter.”
Karl Larsen, a professor in the department of natural resource sciences at Thompson Rivers University who worked with Lomas, is also concerned about encroaching development.
“You can do a lot of interesting things to try and keep rattlesnakes present in the face of development but ... just because you see a rattlesnake doesn’t mean it’s doing well,” said Larsen, noting that Environment Canada has played a vital role in the long-term study of the snakes.
Larsen said there remains a need to educate those unfamiliar with rattlesnake country about conservation and about how little threat the snakes pose to humans when dealt with properly.
Jared Maida, a snake biologist at the Nk’Mip Desert Cultural Centre in Osoyoos, is among those doing such outreach.
“There’s a lot of misconceptions about rattlesnakes and snakes in general,” said Maida, adding he’s handled hundreds of rattlesnakes without a bite.
“A rattlesnake, specifically, is way more scared of you than you are of them. A snake would rather not be seen and not be bothered than anything. It just uses its rattle as a defence mechanism to make it look scary, when essentially what it’s doing is trying to find cover to hide from someone.”
Stephanie Winton, one of Larsen’s graduate students, recently began a two-year study into the impacts of road mortality on rattlesnakes along a five-kilometre stretch of road in White Lake Basin in the southern Okanagan.
“The hypothesis that we’re testing is during the evening, when the temperature starts to decrease, the snakes will move on to the road as it’s a warmer surface and it will help them thermoregulate,” she said.
Winton is monitoring a population of about 220 snakes and counted about 20 killed on the road during May and June, she said.
One concern is how many of those killed are reproductive-aged females, but Winton said the research may also help determine if driver education could play a part in protecting the snakes.
Larsen said he’s planning a pilot study with local vineyards to build “little islands of refuge” where rattlesnakes can linger safely, away from workers.
Such work may prove invaluable for the employees at B.C.’s 252 licensed wineries, which grew in number from 182 in 2010.
A WorkSafe B.C. claim filed in May revealed a commercial vineyard worker in the Interior was bitten while kneeling down on to an adult rattlesnake.
Spokesman Scott McCloy said WorkSafe B.C. couldn’t share details about the case, but noted employers are expected and required to train and supervise workers in B.C.’s rattlesnake-prone areas.
“We expect the employer to have done a risk assessment of the safety issues involved,” McCloy said. “We expect workers to wear proper protective equipment and, first and foremost, sturdy boots with no exposed skin.”
WorkSafe B.C. tallied six claims involving workers bitten by snakes between 2010 and 2014, none of which were fatalities.