Thanks, karen. I took him to my wonderful vet, who x-rayed it and watched him for a day before advising that it needed to be removed. She also said it didn't look like a bite, more like he got it caught on something (so bunny was off the hook). We now call him "Stubby Stuart" and you'd never know he was missing anything! I of course miss seeing his beautiful long tail, but he still has enough to provide balance and he gets around just fine.