Humpback whale head breach photographed off Cape Ann, just 15 miles out of Gloucester. The humpback whale is a baleen whale and a rorqual whale that performs complex and cooperative feeding techniques. The humpback has a bulky head with bumpy protuberances (tubercles), each with a bristle. Humpbacks are acrobats of the ocean, breaching and slapping the water. They live in pods and have 2 blowholes. The name humpback describes the motion it makes as it arches its back out of the water in preparation for a dive. Humpback whales grow to be about 52 feet (16 m) long, weighing 30 - 50 tons (60,000 - 100,000 pounds). The females are slightly larger than males, as with all baleen whales. The four-chambered heart of the average humpback whale weighs about 430 pounds (195 kg).