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Have you ever wondered where exactly a #grizzlybear dens up during long, cold winters in the Rocky Mountains? It might not be where you think-- a thread.
Before we get into showing you some den locations, what have other researchers already found? What does the science on den selection look like? @KEPigeon and team give us a good idea- low disturbance, dry, steep, mountainous terrain, w/ good spring food. https://academic.oup.com/jmammal/article/95/3/559/877570
Previously, @LanaCiarniello compared denning in mtns vs plateau in BC Rockies. Mountian females spent longer in their dens (200 days versus 164 days). Mountain dens were up high, on rocky slopes, plateau dens were under trees with good roots. https://bioone.org/journals/ursus/volume-16/issue-1/1537-6176(2005)016%5B0047%3ADBADSS%5D2.0.CO%3B2/Denning-behavior-and-den-site-selection-of-grizzly-bears-along/10.2192/1537-6176(2005)016[0047:DBADSS]2.0.CO;2.short
Let's see some winter 2019/2020 mountain den locations from the Rockies-- they will likely be in much more rugged terrain than you would've guessed. Take EVGF46 for example, a 5 yo female:
Or EVGF78, an 8 yo female with 1 cub:
EVGF57, a 6yo female (likely will have cubs this year), but didn't last year:
EVGF87, young female. This area is less rocky than the others, but that slope is high and deceivingly steep.
All of these dens are >2000 m in elevation and are all facing west, or north-west. The bears are looking for stable snow (no avalanche, but persistent snow) to cover their den all winter without major freeze-thaw. Hence why they don't den on lower, or more southern slopes=warm
