Two cougar kittens were struck by a train and killed last week in Banff National Park in Alberta, bringing the total number of cougar deaths in the area to five this year.
The collision occurred on a stretch of railway track that runs west of the Banff townsite near Vermilion Lakes on March 18, Parks Canada resource conservation manager Bill Hunt told CBC News on Friday.
CP Rail reported the incident to Parks Canada, which investigated and, according to Hunt, discovered that the dead cougar kittens were male, about five months old, malnourished and likely alone.
"They were emaciated, near starvation. So what this would suggest is that the mother had either abandoned them for some reason, or has been killed, and is no longer able to hunt for them," Hunt said.
"They were in bad shape, and that may have affected the fact that they were struck by a train — either their ability to hear the oncoming train or perceive it, or to get out of the way in a timely manner."
Cougar deaths on railway tracks 'rare'
Two years ago, a pilot project in Banff National Park was established that cut escape trails along a rail line to reduce wildlife mortality rates.
Experts said that train speed and track curvature make it difficult for wildlife to detect trains, while being close to water hinders their ability to get off the tracks before being hit.
However, Hunt said the cougar kittens were struck on a section of railway track that is straight and along good sight-lines.
And unlike bears or wolves, cougar deaths on railway tracks are a rare occurrence. Wary of noise and extremely elusive, cougars are typically nimble, fast and astute, Hunt said.
But the necropsy performed on the kittens suggested that before they were killed, they were already near death — which, according to Hunt, could have blunted their ability to perceive danger.
An important factor in their deaths is that there were no signs of an adult cougar nearby, and at their age, Hunt said the kittens should have been learning to hunt from their mother.
They can spend upwards of their first 26 months learning those survival skills, and still sometimes struggle in the wild as "teenagers" on their own for the first time.
"They haven't learned hunting skills well enough to take down other wildlife, like a deer or things like that," Hunt said.
"These kittens were much younger than that; they were much smaller, and certainly at an age where they would be capable of going after small prey like a snowshoe hare or something, but would be relying on the mother to feed them."
Keeping people out of wildlife corridors key, expert says
The kittens are the fourth and fifth cougars to die in Banff National Park in 2021.
A malnourished adult had to be euthanized after it was hunting in the townsite on Jan. 13.
Two weeks later, the body of a young cougar was discovered on Tunnel Mountain.
The same day, an adult female died of respiratory failure while recovering from a radio collar fitting procedure, and officials said testing determined that she had a pre-existing lung condition.
While Hunt said park officials do not believe the cougar kittens were related to those that have died so far, they will be testing their DNA to look for connections.
And in spite of these deaths, he said the park's cougar population numbers remain healthy.
"Three of those [deaths] were young of year, and so it's not uncommon for these young carnivores to have high mortality in that first year, where they're struggling to learn to feed and forage on their own, and have a lot of potential risks out there," Hunt said.
"For me a key piece is just that sort of struggle with maintaining wild, wary carnivores if all the prey is hiding in town. It speaks back to that part of keeping people out of wildlife corridors and keeping wildlife out of residential areas."