I too had 3 geese, all boys but during the breeding season they were vicious, one of them got hell from the other 2. I used to seperate them but they would fly to where the others were. I seperated them at night and then weeks later we locked them up together and in the morning the bullied one had been badly beaten up again. After the breeding season calm was restored.
The one that was bullied was eventually caught by the fox as he must have been the weakest of the 3. As much as I care for them and have a lot of time for them they can be bad buggers though!