Well, that wasn't until Brian Mulroney's overly extended stay on Sussex Drive (the prime minister's residence) back in the 1980's. It was under Brian Mulroney's reign that the "Loonie" (Canadian one dollar coin) came into existence. Prior to that we had paper dollars...and there were a few silver dollars minted now and then...but they were not called "Loonies". The Loonie is called the Loonie because it has the image of a loon on its front side, and the Queen, of course, on the back side as usual.

A loon is not precisely a duck, but it is a water bird.