We have quite a few geese around our local pond and a couple of great blue herons that visit regularly to fish. Mostly they get along but one day when, I guess, one of the geese got closer than the heron liked, he assumed an aggressive posture and it was interesting to see how quickly the goose backed off. The geese are much heavier and sturdier looking birds but the heron was much more fierce looking.
https://365project.org/gardencat/365/2014-08-05