Humpback Whale - Megaptera novaeangliae

Humpback Whale
Megaptera novaeangliae

Other Names: Hump-backed Whale

Habitat: Inshore and offshore

Status: Rare

Population: 12,000-15,000

Threats: Entanglement in fishing nets, pollution, and human disturbance

Group Size: 1-3, large groups at feeding and breeding areas

Fin Position: Far behind center

Newborns: 13'1/4"-16'1/2"(4m-5m), 1-2 tons

Adults: 37'3/4"-49'1/4"(11.5m-15m), 25-30 tons

Diet: Krill or other crustaceans and fish

Baleen: 270-400 baleen plates on each side

Description

Dorsal fin:

- pronounced hump in front of fin
- low, stubby fin (highly variable) with broad base

Flukes:

- blue-black or black upper sides
- black and white patches on underside (variable)
- distinct notch in middle
- S-shaped trailing edges
- broad with irregular, knobbly trailing edges

Flippers:

- exceptionally long flippers, with knobs along leading edges
- atlantic humpback - flipper usually white on both sides, some with black markings

Head:

- prominent splashguard
- baleen relatively short and wide: maximum length 28-39 in (70-100 cm); maximum width 12 in (30 cm)
- rounded projection near tip of lower jaw appears to increase in size with age
- throat grooves

Head (from above):

- 2 distinct blowholes
- single indistinct ridge from blowhole to near tip of snout
- knobs along central ridge and in haphazard arrangement elsewhere

Other characteristics:

- knobs on top of head and lower jaw
- head slender in profile
- blue-black, black, or dark gray upper side
- large, stocky body
- male may be scarred from fights (usually around dorsal fin)
- relatively narrow tail stock
- underside may be completely black or white, but usually partially white
- 12-36 widely spread throat grooves
- may be small circular scars from barnacles and white marks on head
- rounded projection near tip of lower jaw

Behavior

- may breach, lobtail, and flipper-slap several times in a row
- often spyhops
- may lie on its side or back, holding one or both flippers in the air
- shows little fear of boats and may be highly inquisitive
- slow swimmer
- dives usually last 3 to 9 minutes (sometimes up to 45 minutes), followed by 4 to 8 blows at 15 to 30 second intervals; at breeding grounds, usually blows 3 to 6 times between dives
- males can be very aggressive toward one another when competing for females
- has many different feeding techniques

Distribution

- widely distributed in all oceans from the poles to the tropics
- wide-ranging but with distinct seasonal changes in distribution
- spends winter in high-latitude, cold-water feeding grounds and summer in low-latitude, warm-water breeding grounds, migrating thousands of miles between the two
- appears to be divided into at least 10 geographically distinct populations, though apparently with some mixing; southern and northern hemisphere populations, however, probably never mix
- population in northern Indian Ocean may be resident year-round, or may migrate to and from Antarctica
- northeast Atlantic population as low as a few hundred
- spends much of year fairly close to continental shores or islands, breeding and feeding on shallow banks, but migrates across open seas

e-mail questions, comments, and/or suggestions to
wcrc@sci.tamucc.edu

Internet Coordinator: Candice Orca Mottet

e-mail questions, comments, and/or suggestions to wcrc@sci.tamucc.edu

e-mail questions, comments, and/or suggestions to
wcrc@sci.tamucc.edu