Just watched some of the bears feeding on salmon and noticed they don't eat the whole thing. After reading up on it, it seems they only the high-fat parts such as the brain, skin and eggs. Another interesting thing about bears is that they don't urinate or defecate for the whole winter while in hibernation. Quoting the site I was reading, they "plug their anuses with a mixture of feces, hair and bedding material called a ‘tappet.'" And the females give birth while asleep.