Researchers from NASA and the medical professions are very interested in denning physiology. They are trying to figure out how bears can sleep for up to 8 months without eating, drinking, urinating or defecating, yet when they awaken they have lost little bone mass or muscle tone and have no signs of uremia. Understanding this could help astronauts during extended space flights or patients who are bedridden. They actually spend more time eating grass, plants and berries than meat. Fish are an important part of their diets, but few Kodiak bears expend the time or effort necessary to chase and kill mammals.
Bears use the most nutritious parts of their food to maximize their weight gain.
Grass and forbs are only used while they are rapidly growing in the spring and early summer. Brains, flesh and eggs are preferred parts of the salmon. Internal organs of deer, elk and cattle are eaten first when one is killed or scavenged. Berries are used most often when they are ripe and sugars are at their highest level. Because of the rich variety of foods available on Kodiak, bears here have some of the smallest home ranges of any brown bear population.