As winter warms, bears can’t sleep
By Kendra Pierre-Louis, New York Times
There are certain axioms about the natural world we learn as children. The sea is salty. Plants grow toward light. Bears hibernate in winter.
But as climate change leads to warmer winters, later falls and earlier springs — which can disrupt both food supplies and biological rhythms — American black bears are changing their hibernation routines, scientists say. In some cases, bears are not hibernating at all, staying awake all winter. In others, bears are waking from their slumber too early.
For every one degree Celsius that minimum temperatures increase in winter, bears hibernate for six fewer days, a study found last fall. As global temperatures continue to rise, by the middle of the century black bears may stay awake between 15 and 39 more days per year, the study said.
It’s my belief that here in the Tahoe Basin, and I have plenty experience with urbanized black bears in the winter, that it’s not so much about global warming as it is about lazy humans providing access to human food and trash 52 weeks a year. A black bear dens because in nature they generally don’t have access to natural food sources in the winter, where as these urbanized bears are being provided a food source year round…………by HUMANS!