Do they just use the fur when they fur trade?
Beaver fur fibers, by itself, is used for making felt hats but that is a small portion of the overall trade. Sometimes the entire animal is utilized in some form so that nothing is wasted. For example, farm-raised mink also produce a very nice oil which is used in cosmetics. And a trapper will enjoy a beaver steak from the beaver he has hunted and caught. Otherwise they dispose of the bodies and just use the fur.