We have four embden goslings, about one month old, just starting to get real feathers on their shoulders, and the ledge where the wings rest. At night they are closed into their hutch, and during the day they are on grass. Night and day, they have access to grain and water. The last several days, they have started to develop bald patches on either side - right where the feathers are coming in where the wings rest. The skin looks irritated, and I can see stumps (some of them red) where feathers have been pulled out. We never see them pulling feathers, but it seems to get worse over night. What is going on? Are they likely pulling eachother's feathers or their own? What can we do about this?