Q: I have ferret that’s approximately 4 years old. He is starting to show aggression toward my other male ferrets when bedding up. He grabs or chews on their ears, causing them to squeal. I have to pry his mouth open for him to release. Any ideas why he is doing this?
A: At this age, sudden signs of aggression are often related to adrenal gland disease. Make an appointment with your veterinarian to have your ferret checked out.
You didn’t state whether he is picking on ferrets that are new or those that he has lived with for a while. If the ferrets are new to the household, he could be trying to engage them in play.
My best guess, though, is that this behavior is related to adrenal gland disease, especially because your ferret recently started the behavior.