Why Did Pygmies Fight Cranes?

Pygmies were an African tribe who  lived on the southern shores of the great, earth encircling river. They were engaged in eternal war with flocks of migrating cranes. Pygmies were short, dark-skinned men who grew to be the foot of one pygmy. Pygmy was a unit of measure from the length of a man's elbow to knuckle bone (about 1 and 1//2 ft). The pygmies lived in India and sub-Saharan Africa

Picture: http://www.theoi.com/Phylos/Pygmaioi.html