Baby goose fights big duckling for reasons unknown

From my YouTube channel from a while back.
Before getting some baby Chinese Swan Geese, I had never seen baby geese fight before. That was weird.
That goose child there is half Chinese Swan Goose. His name is Calvin. When he grew his adult feathers in they were a beautiful black grey and white splotchy pattern. Breeding white geese and darker colored geese together make for fantastic looking descendants.