Toward the end of each summer, grizzly bears in Alberta’s Rocky Mountains gorge on the tart red berries of a shrub called Canada buffaloberry (Shepherdia canadensis). Lacking the salmon of coastal populations, the feast is the largest caloric event on an Alberta grizzly bear’s menu. This is the time when individuals gain much of the weight needed for hibernation.
But our latest research, published in the journal Nature Climate Change, shows that rising temperatures are advancing the development of plants like buffaloberry, pushing forward the timing of this annual buffet.
By the year 2080, buffaloberries in the Rockies will ripen nearly three weeks earlier than they presently do. We predict this change will alter the behaviour of the region’s grizzly bears, and perhaps threaten the reproductive rates of this vulnerable population.
Our work is based on a horticultural principle well-known among Canadian gardeners: that plant development is tightly linked to temperature accumulation. A plant needs a certain amount of heat to proceed from one phenological stage to the next—from flowering to fruiting, for example.
Continue reading at University of Alberta.
Image via University of Alberta.