While government scientists have documented a huge array of food resources available to omnivorous grizzlies, it is worth noting that one food source is not necessarily equivalent to another in quality and availability. Steak does not equal celery.
There are also temporal and spatial aspects to the food resource that must be considered, as well as caloric and vulnerability costs associated with obtaining alternative food sources.
Of four main food sources two, whitebark pine and cutthroat trout, have completely collapsed and their recovery is doubtful. Another important food source, Army cutworm moths, are only available at very high altitudes and well documented climate change trends threaten to curtail their availability
Changes in food resources are driving grizzlies to consume more meat which in turn is putting them at greater risk of conflict with hunters and livestock with the prospect of unsustainable levels of mortality.
We believe that food source disruptions are symptomatic of climate change and that further disruptive ecosystem-wide changes are not only possible, but likely, and will significantly impact grizzly bears