Australia v England.

Up and down they go on the river Avon. Every morning, the black swan chases the mute downstream to the hatches, they turn, and its a chase all the way upstream to the bridge. About a 1000 yards. The black swan will just not accept any intrusion on his territory.
The amount of energy they use up in this game is huge. And what puzzles me is never seen the blacks fly. There are about a dozen of them on the upper river around here, they just can`t stand the natives.