Why is there more white sheep than black sheep

Why is there more white sheep than black sheep?

Once upon a time there was a sheep farmer named Fred Dagg who only wanted white sheep in his paddocks. He used his special powers by casting a spell on all the rams so that they only produced lambs with white wool.

Unfortunately, the spell wore out and some lambs were born with black wool. Big Joe, the farmer from down the road who really liked black sheep, would sneak down in the middle of the night to steal the black sheep that were born. He was worried that Fred Dagg would kill them. Big Joe had friends who also liked black sheep so he shared them around and that is why we now have some black sheep all around New Zealand.