I have 2 American toads. 1 male, 1 female. Within the last 2 weeks I've noticed that the males throat becomes partially inflated, it's not huge, just kind of a small bubble. It's not like that when I feed them, it seems to only be when he's just sitting around. I have no idea why it's doing this, and I was wondering if there is possibly something wrong? I've never hibernated them, so I know it doesn't have anything to do with breeding. Any ideas what could be causing it? Should I be concerned?