Humpback whales were given this common name because of the shape of their dorsal fin and how they arch their back as they dive; this motion emphasizes the hump before the dorsal.
The scientific name, Megaptera, means "large winged" and refers to their long, white, wing like pectorals which may be as long as one third of the whale's body length.
Each whale has a unique pattern on the underside of its tail fluke, which can be used as a fingerprint for researchers to identify individual whales. Humpback whales can live up to 70 years of age, the average being approximately 50. The females are larger than the males, and can measure from 45 to 50 feet (13.7-15.2m). A male measures from 40 to 48 feet (12.2 to 14.6m) They can weigh from 25 to 45 tons ( 22,680 to 36,287 kg). They reach sexual maturity at 6-8 years of age. A female may give birth once every 2 to 3 years, the gestation period being 12 months. A calf will nurse from 8-11 months of age and, once weaned, they are 24 to 27 feet in length. They will leave this mother-calf bond generally following the next spring migration to feeding grounds.