Canadian Rockies Wildlife

Grizzly Cub of the Year in Hyperphagia

The Fall months witness Grizzly Bears eating and drinking almost nonstop to put on weight in preparation for winter hibernation. During this stage called "hyperphagia", Grizzly Bears may consume ten times as many calories as they need during the spring and summer if they are going to den up in good condition. This shows the same Grizzly Bear Family as they were this past July and now much larger during hyperphagia, very actively digging for what we think might be tubers. Large amounts of water are needed to process these large amounts of food and rid the body of nitrogenous waste.

After hyperphagia, when metabolic processes start to change in preparation for hibernation, Grizzly Bears eat less but continue to drink to purge body wastes. Resting 22 or more hours per day just before hibernation(often near water), sleeping heart rates begin to fall from 66-80 beats per minute to less than 22 beats per minute.