I read this and thought to myself - hmmmm. "when have my ferrets started biting (or gone from lick,lick,nibble to lick,lick,CHOMP!)" I've actually thought about this quite a bit since 1997. And I have decided that there are three (or two, depending how you count it) obtuse signs that *something* isn't quite right with a precious little one. We all know that lack of appetite or lack of energy can be a very serious sign that something is wrong with any pet. My three signs are parasites-like fleas (where there hadn't been any before), the change from lick, lick nibble to lick, lick, CHOMP; and new biting behavior. When I look at it that way, Miji and Nanna gave me a couple of month's notice that something was wrong. I just wasn't listening. When I was in college, I had a cat that spontaneously got fleas and lost his hair on his rump when I moved in with this 'friend.' None of the other animals had fleas (or at least not as many). And of course, the others had their hair. Not more than a month after I moved out of that house did my cat get rid of the fleas (mostly on his own, since nothing I had done earlier seemed to make any difference), and he grew back his hair. He was just stressed living there (not that I blame him at all!) Trixie started biting much more after I boarded her and the others for a weekend while I was out of town. The rest of my 'business' didn't mind the stress of being moved, of being away from 'mommy' and not getting the out time they were used to. But it was just too much for little sensitive Trixie. In my mom's ferrets, two of them displayed severe aggression in addition to the other signs of adrenal, as well as becoming more nippy. After their surgeries, they both returned to normal. And I believe that my Miji and Nanna warned me something was wrong with their biting behaviors. I should have had them given tests for cancer, if I had known. So, to make a long narrative longer, I would suggest looking to see if something in his environment has changed (did you get a new stereo and maybe play music more loudly than before? A new house guest? New furniture?) and also seriously consider giving him a full medical check up. Good luck. Love to all fuzzies. Trish & Crew [Posted in FML issue 2929]