I had a similar experience with one of my ferrets. Her tail is squared off instead of tapered and covered with a fur tip. You can actually see the skin at the end of it. I got scared as the fur got shorter and thought she might have some terrible disease so I rushed her to my vet. After a careful exam under bright lights he laughed and asked me which one of the ferrets was a barber! Turns out someone is clipping her tail short. I haven't caught the culprit yet and there is no chewing or biting just a nice neat clip. He suggested bitter apple but you wouldn't want to use that on whiskers. Laurel [Posted in FML issue 2359]