Humpbacks use at least two methods of feeding. If krill is centred near the surface of the water they use a method called lunge feeding. At high speed the whales lunge up from below breaking the surface with vast mouths agape; taking a huge gulp of krill and water.
Bubble-net feeding is another method used by the Humpbacks in their quest for food. Their technique is to dive beneath a swarm of krill and blow a series of bubbles which has the effect of concentrating the krill. The humpback, or two humpbacks working in tandem, will then spiral up to the surface in the centre of the bubbles, with mouths and upper belly fully extended, catching everything in their wake. Many a sea bird has been taken in the rush for food. Humpback whales have skin grooves on the lower jaw and upper breast plates which allows them to expand their upper body which, when full of krill and water, resembles a huge balloon.
ABOVE: Whalers knew that where they found Krill they would find whales, the darker sections of this map show concentrations of whale kills, the lighter sections show known areas where Krill can be found.
(Image source: The Natural History of Whales and Dolphins, Evans 1987)