By Kayla Heinze, Communications Specialist
Shaking off his snowy slumbers, a grizzly bear emerged from his den in early March and found his way to a bison carcass that had been decomposing in Yellowstone National Park’s Pelican Valley. Spotted by a park biologist on March 7, the adult male marked the year’s first confirmed sighting of a grizzly in the park.
While not as consistent as other spring milestones like the equinox or Daylight Savings, this first sighting is a useful way for all of us invested in the well-being of bears to stay attuned to the shifts in their annual cycles.
An outsize, Western version of the famous Pennsylvania groundhog Punxsutawney Phil, the first grizzly’s awakening clues us in that the hard days of winter (when other species rule the landscape) are melting away. Yellowstone’s announcement informally denominates the end of hibernation, prompting park officials to start promoting bear safety precautions and begin seasonal closures in heavy bear-use areas.
But, just like the gradual greening of the still-frosty landscape, the emergence of grizzlies comes in waves. Male bears, like the early bird recently seen in Yellowstone, are typically the first to snap out of their winter torpor. Having depleted much of their hibernation fat stores, they quickly make their way to early-season foods — typically ungulate remains, like elk and bison, leftover from the harsh, cold months, or fresh plant shoots just beginning to poke out of the snowpack.
As park officials reminded in their news release, vigilance by humans is especially important right now since hungry bears can react aggressively while feeding on carcasses. After months of happily slaloming the ski slopes while grizzlies rested, this time of year can catch us by surprise. Getting back into good habits of bear-safety recreation is as essential as any other spring cleaning project, and is one way we can be good neighbors to wildlife while still enjoying the beautiful and bountiful ecosystems we share with them.
Climate impacts on grizzly recovery
Later in April and early May, sows with their newborn cubs will take their initial steps out into the lengthening spring sun. Cubs are typically born in January, making them still highly vulnerable when they exit dens with their mothers.
Coincidentally falling on the same day as last year’s first sighting, the Yellowstone bear report last week nevertheless occurred in a world where seasons are less certain. Writing about this topic last year on the Vital Ground blog, conservation writing intern Lena Beck noted that the date grizzlies exit their dens is tied to local weather patterns. This means warmer and earlier spring weather brought about by climate change could alter denning behavior and lead to first sightings sooner in the year. U.S. Fish and Wildlife Service biologist Wayne Kasworm said that these earlier emergences are most concerning in their potential to increase cub mortality, as the young bears would have fewer weeks to develop within the safety of their dens.
Grizzly cubs are precious individuals, offering hope for the long-term recovery of the species. As a mammal with relatively low and slow reproductive rates that also faces genetic diversity problems in some populations, increased cub mortality from changing weather patterns could be truly threatening to grizzlies’ species-level health in the Lower 48.
Whether solitary males eager to get outside and look for food and mates or mothers tending carefully to their offspring, all bears and all species benefit from protected habitat. Projects like our capstone effort at Bismark Meadows and our recent easement at Salmon Prairie offer just two examples of wetland areas with early spring plant growth now conserved with the help of conservationists like you.
These places and many more Vital Ground projects will permanently protect areas that provide ample spring forage for bears and other wildlife — giving these stunning creatures a fighting chance as they open their eyes to an ever-changing world.