The death toll for black bears in the mountain national parks is rising rapidly.
Six black bears have been struck and killed by vehicles and trains in Banff, Yoho and Kootenay national parks since early June – four on roads and two on the Canadian Pacific Railway line.
Parks Canada officials say the latest human-caused mortality was on Sunday (July 9) when a black bear was hit and killed near the turnoff from the Trans-Canada Highway to Banff’s industrial compound – a few hundred metres from a wildlife underpass.
Jon Stuart-Smith, a Parks Canada human-wildlife conflict specialist, said the number of bear deaths is unfortunate.
“Although this does seem like a spike in a short period of time, it also depends on what happens over the rest of the year,” he said. “It can vary from year-to-year. For example, we lost nine in 2014 and in 2012 we lost 17.”
Black bears primarily use the montane region in Banff National Park – 80 per cent of which lies within the Bow Valley – and that’s the area with the most human activity and development.
Black bears are thought to be more resilient to human-caused mortality and habitat fragmentation than many other carnivores due to higher birth rates, including a younger age of first reproduction than grizzlies, higher population densities and a greater overall tolerance to human disturbance.
But despite this and the fact that the population status for black bears in the Bow Valley has not been quantitatively examined, scientists say that cumulative effects of human activity may be causing mortality to approach a critical threshold.
Tony Clevenger, a Bow Valley-based research scientist who specializes in identifying the effects of highways and other barriers on wildlife connectivity, including analyzing factors that contribute to wildlife-vehicle collisions, points to a population viability analysis more than a decade ago that suggested the Bow Valley was a population sink for black bears.
“I don’t think things have changed here in the Bow Valley to turn that result around,” said Clevenger, noting a sink population is when mortality rates exceed birth rates and immigration exceeds emigration.
“If anything, given the increased tourism in Banff National Park and human footprint in Canmore and Dead Man’s Flats, the sink is going to get wider and deeper and it’s going to be difficult to keep a healthy population of black bears in the valley.”
Black bears don’t seem to be on the radar in the national parks like grizzlies and wolves, but Clevenger said in some ways they may be a better indicator of management success.
The first black bear death of 2017 occurred about four weeks ago on the Trans-Canada Highway west of the Norquay exit. The second mortality was on the train tracks in Yoho just below the Spiral Tunnels on June 16.
Another black bear was killed on the train tracks June 27 near Protection Mountain campground in Banff, while yet another bruin was struck on the Icefields Parkway near Rampart Creek on July 4.
Then on July 5, a black bear was struck and killed on Highway 93 South in Kootenay National Park, near Mount Wardell between Vermilion and Kootenay Crossing.