Two grizzly bear cubs thought possibly struck and killed by a train in Banff National Park last fall have shown up alive and well.
Canadian Pacific train crews reported striking one, possibly two, young-of-year cubs last October in the Muleshoe area about 10 kilometres west of the Banff townsite. An extensive search failed to turn up any physical evidence of a strike and footage from a camera mounted on the locomotive was inconclusive.
Parks Canada officials say there have been recent sightings, including along the train tracks, of female bear 130 with yearling cubs. Recent photos of the bear family provided additional confirmation the cubs are alive.
“The outcome of that train incident was uncertain. I did see some camera footage from the train and I personally felt it was unlikely those cubs had survived,” said Steve Michel, human-wildlife conflict specialist with Banff National Park.
“I’m pleasantly surprised they’re alive. It’s great news.”
CP sent an email response to the news. “CP is happy to hear that these bear cubs have emerged,” wrote spokesperson Salem Woodrow.
Grizzly bears are a threatened species in Alberta.
Trains are the single biggest killers of grizzly bears here, with at least 17 bears killed on the tracks since 2000, taking a toll on the slow-reproducing population of about 60 bears.
Bear 130, a somewhat wary animal, has had a tough time raising cubs in the busy Bow Valley. She lost two yearling cubs on the train tracks in October 2012, also in the Muleshoe region – an area referred to as a “killing field” for bears.
Then, in 2014, a large male bear killed her two cubs. “She lost two cubs of the year to infanticide,” said Michel.
Meanwhile, Parks Canada has confirmed two other grizzly bears have shown up this spring with new cubs, including bear 138 with two in the Lake Louise area, and an unmarked female with one cub spotted at Lake Minnewanka.
Remote cameras scattered throughout Banff, Yoho and Kootenay national parks shows there are, on average, about 20 grizzly bear family groups. In an average year, there are about five female bears that have cubs of the year.
It’s also not known about other bears deeper in the backcountry because Parks has not yet collected the camera data.
Parks has confirmed 142, 143, 148 and 160 have not had cubs this year. This time of year is the heart of breeding season, and some of these bears have been observed breeding with males.
Implementation of fertilized eggs, however, is delayed until the start of denning season, typically in November. If a female does get enough body fat or weight during summer and fall, the embryos will not implant in the uterus.
Michel said female bears need to reach a critical threshold of body fat, ideally about 24 per cent, for successful gestation.
“The worry in the central Rockies is they depend almost entirely on the health of the buffalo berries,” he said.
“If we have a good shepherdia season, that is their primary source to put on necessary body fat. If not, the likelihood of successful reproduction is going to be reduced.”
