Why are my geese so mean to my runner?

[bock]

I have 9 female ducks, 1 male duck, and 2 unsexed chinese geese, all 13 weeks old, from Metzer Farms.

A few weeks ago I caught the White Chinese goose pinning down the female Black Indian Runner in the water, until it seemed like she was drowning.

Today I heard a bunch of quaking, and my Brown Chinese Goose had the black Runner by the neck, and was thrashing her around.

I ran in the pen and had to take the goose off the duck. After they were seperated the goose kept on choking on all the feathers it had pulled out. The duck does not seem to be lowest in the pecking order, she is always one of the first to the food and in the pool. I have seen no other agresion in this flock, just between the geese and the black Runner I really don't understand it, why are they doing this? Is there anyway to get them to stop? Thanks, I appriceate it.

 

[CMV]

Are your geese ganders? I think you might be seeing some confused mating behavior. I had a batch of geese that constantly targeted one duck in the same way. It got to the point where I had to remove the geese from the situation. Upon butchering the geese I discovered that all the geese that were problematic were males including one I had pegged as a female. After finding out they were all male it became clear that their behaviors were attempts at mating. I just thought the geese didn't like the duck before that.

 

[bock]

That is what I thought when I saw the goose pinning her down in the pool, but they are only 13 weeks old. Isn't that a little young to start mating?

I am thinking both the geese are ganders though

, I guess I will Have to get some females next year.