The Humpback Whale (Megaptera novaeangliae) is a species of baleen whale. It is a rorqual; a member of the family Balaenopteridae. Adults range in length from 14–17 m (46–56 ft) and weigh up to 40 metric tons (44 short tons). The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. It is known for breaching and other distinctive surface behaviors, making it popular with whale watchers. Males produce a complex song typically lasting 4 to 33 minutes.

Found in oceans and seas around the world, humpback whales typically migrate up to 16,000 km (9,900 mi) each year. They feed in polar waters and migrate to tropical or subtropical waters to breed and give birth. Their diet consists mostly of krill and small fish, and they use bubbles to catch prey. They are promiscuous breeders, with both sexes having multiple partners. Orcas are the main natural predators of humpback whales.

Like other large whales, the humpback was a target for the whaling industry. Humans once hunted the species to the brink of extinction; its population fell to around 5,000 by the 1960s. While numbers have partially recovered to some 135,000 animals worldwide, entanglement in fishing gear, collisions with ships, and noise pollution continue to affect the species.

The humpback was first identified as baleine de la Nouvelle Angleterre by Mathurin Jacques Brisson in his Regnum Animale of 1756. In 1781, Georg Heinrich Borowski described the species, converting Brisson's name to its Latin equivalent, Balaena novaeangliae. In 1804, Bernard Germain de Lacépède shifted the humpback from the family Balaenidae, renaming it B. jubartes. In 1846, John Edward Gray created the genus Megaptera, classifying the humpback as Megaptera longipinna, but in 1932, Remington Kellogg reverted the species names to use Borowski's novaeangliae.[5] The common name is derived from the curving of their backs when diving. The generic name Megaptera from the Ancient Greek mega- μεγα ("giant") and ptera/ πτερα ("wing") refer to their large front flippers. The specific name means "New Englander" and was probably given by Brisson due to regular sightings of humpbacks off the coast of New England.

Humpback whales are rorquals, members of the Balaenopteridae family, which includes the blue, fin, Bryde's, sei and minke whales. A 2018 genomic analysis estimates that rorquals diverged from other baleen whales in the late Miocene, between 10.5 and 7.5 million years ago. The humpback and fin whale were found to be sister taxon. There is reference to a humpback-blue whale hybrid in the South Pacific, attributed to marine biologist Michael Poole.

Images in this gallery are mainly from the Pacific Coast off Monterey California. Older images are from Alaska, Commander Islands and the Atlantic Humpbacks of Svalbard.