Scottish Fairy and Folk Tales, by George Douglas, [1901], at sacred-texts.com
THE fox is very wise indeed. I don't know whether it is true or not, but an old fellow told me that he had seen him go to a loch where there were
wild ducks, and take a bunch of heather in his mouth then go into the water, and swim down with the wind till he got into the middle of the ducks, and then he let go the heather and killed two of them.