I have a flock of 7 geese and 8 ducks that I currently keep together in one pen. They've gotten along well for nearly a year now, with the geese typically staying in their own group for most of the day and intermingling here and there. However, one goose has suddenly started isolating from the rest of the group. He (I think he's a gander) stays far from both the geese and ducks throughout the day. His feathers have also started to look super wet while the rest of the geese look fine, despite the rainy weather. I didn't think much of it until I put them away the other night and saw the main gander attack him, biting at his wing with no intention of stopping. Now the soaking wet gander refuses to go in the pen with the others or even be near them at all. I'm not sure if this is mating season behavior or if the wet gander might be sick or what I could do to help. I don't want to isolate him from his flock, but it seems like he's too afraid to let me put him in with the rest of the birds. I can't think of what else to do at the moment but keep him separate, though this can't be a permanent solution.