4 weeks ago I found a 6 week old baby squirrel dragging himself along side the road. I brought him home, warmed him up,rehydrated him and bought esbilac. I didn't want to mess with him too much because he was terrified, screaming at me, so I left him in a cat carrier with a heating pad and fed him every three hours. Had a swollen face and he would move his feet, just kept his hips tight. Noticed an already healing broken leg. Two days later many Abscessed puncture wounds appeared. Put him on amoxi for one week and cleaned and treated the wounds. He did great. Very Tip of his tail had exposed bone which fell off in a bout two weeks. He's been in a cage that I've used before to rehab squirrels and he's thriving. He gets around perfectly even with a slightly crooked leg. However today I noticed that his tail is losing fur and perhaps he doesn't have much use in his tail. One of the puncture wounds was near tail on his lower back. It is not completely limp but he does not curl it like a normal squirrel. I'll attach a picture of what the skin looks like. Just wondering if it's a skin condition or that he has no circulation and will lose more of his tail.
Thank you for taking care of this little squirrel! It's certainly possible that he may lose more of his tail if the circulation has been compromised.
Since he does not seem to have full use of his tail, the hair loss may be due to breakage of the hair shafts by rubbing against objects in his cage, especially if he is dragging his tail. It's also possible he may be chewing his tail if there's any discomfort at all.
Parasites, such as mites, may cause hair loss. Fungal infections can cause skin lesions as well.
If you haven't already, I would recommend visiting your veterinarian (who is comfortable with wildlife) for a checkup on this guy. That way, the hair loss can be addressed further and changes or treatments can be made to correct the problem.
I hope this gives you a little direction as to what the problem may be. For the best answer, I would consult with your veterinarian who can give a complete examination of the squirrel.
Thank you for your question and for including the picture! If you have any other questions, please let me know.