Researchers are developing a system to warn grizzly bears about approaching trains in response to climbing death rates, which have some fearing for the future of the species. Some 51 bears were killed in Montana's Northern Continental Divide Ecosystem, including Glacier National Park and parts of the Flathead and Blackfeet reservations, in 2019. The same number of deaths were reported as a record high in 2018, up from 29 deaths in 2017, reports the New York Times. While some deaths were attributed to wildlife management, poaching, and collisions with cars, eight bears were run over by trains, about 25 of which pass through the grizzly bear recovery zone each day. Five bears were killed by trains on the Blackfeet reservation in October alone, though the Times reports "the long-term average for grizzly deaths by train is two a year."
The bears were reportedly enticed by cow carcasses near the tracks that weren't reported expeditiously. A wildlife biologist notes trains "are amazingly quiet on the downgrade and there are a lot of times the sound is blocked, coming in and out of the valleys." Amid fears that too many deaths could prevent a merging of the region's bears with those in the Greater Yellowstone Ecosystem—"considered critical for the long-term genetic viability of grizzlies in the Lower 48," per the Times—University of Alberta researchers are testing an alarm activated by train vibrations. After all, a 2019 study identified train strikes as a leading cause of death among grizzlies in Alberta's Banff National Park. But Montana state biologist Cecily Costello suggests train deaths are tied to "way more bears" in the region. She says the population remains sustainable at 1,051, up from about 400 in 1975. (Read more grizzly bear stories.)