I can do you one better there. My wife and I used to be zookeepers. We had an island at the zoo that housed spider monkeys that was surrounded by a moat containing Australian black swans. One of their favorite hobbies was chasing geese (and people) out of the immediate area and they're large enough that they bruised several of us when they were on eggs and we had to go over to the island (twice daily) or had to bring them in for vet care or transport.