I was thinking that they have a border collie behind them and the shepherd ready to close a gate. My Uncle only had geese once. They are so dirty. Yes they do make good watch dogs. Ducks not much.
Shole Creek is about 3 miles from here has a whole gaggle of em' that expect us to bring them food & chase us & even nip on occasion, & leave droppingson the walkway. yuk, but still everyone loves em.