This way they can track individuals as they migrate thousands of miles. Each animal's fluke is unique, like our fingerprints. Males can sing for a half an hour at a time. Since it happens in the breeding grounds, it is thought to be a courtship ritual. Scientists speculate this behavior can rid them of skin parasites, but it is probably just fun.
Humpbacks migrate each year from polar water feeding grounds to tropical water breeding grounds.
They typically travel in groups of four to 12 individuals. In the cold water, humpbacks feed on krill, sardines, anchovies and other small schooling fishes. Smarter than the average bear, humpbacks encircle fish schools with nets of bubbles. Individuals swim around the school, blowing columns of bubbles, which herd the fish into a tight ball. Cooperative feeding among gentle giants.