The soils can collapse easily unless the top four inches are frozen, so bears must wait, usually until mid-October, for a hard freeze before excavating their dens. Brown bears on the Refuge are faced with a long winter hibernation and limited food resources. As a result, they have small bodies, low reproduction rates, and slowly maturing young. This northernmost population has remained remarkably stable, however. The only enemies these monarchs have are old age, other brown bears, and occasionally man.
Brown bears are plentiful on the Refuge.
Without these magnificent animals, the special wilderness quality of the Arctic Refuge would be greatly diminished.