Megaptera novaeangliae (Humpback whale)

boggelrugwalvis [Afrikaans]; Buckelwal, Pflockfish, Knurrwhal [German]; baleine à bosse [French]

Life > Eukaryotes > Opisthokonta > Metazoa (animals) > Bilateria > Deuterostomia > Chordata > Craniata > Vertebrata (vertebrates)  > Gnathostomata (jawed vertebrates) > Teleostomi (teleost fish) > Osteichthyes (bony fish) > Class: Sarcopterygii (lobe-finned fish) > Stegocephalia (terrestrial vertebrates) > Reptiliomorpha > Amniota > Synapsida (mammal-like reptiles) > Therapsida > Theriodontia >  Cynodontia > Mammalia (mammals) > Placentalia (placental mammals) > Laurasiatheria > Ferungulata > Cetartiodactyla (even-toed ungulates and cetaceans) > Whippomorpha > Cetacea (whales, dolphins and porpoises) > Family: Balaenopteridae (rorquals)

Humpback whales, all taken on pelagic trips off the coast of Cape Town, South Africa. [photos Trevor Hardaker ©]
Humpback whale. [Illustration Noel Ashton ©]

Identification

This is a large baleen whale of up to about 21 metres in length (average 14 m) and weighing in at between 35 to 40 thousand kilograms. It has a broad, rounded head, deep grooves in the throat, a robust body and large tail flukes. The most characteristic feature of the Humpback are it’s huge flippers that can be up to 5 meters long.The Humpback posses a small dorsal fin set well back towards the tail, with the fin itself being set on a fleshy hump, a unique feature to this baleen whale. The body is a dark grey and umber brown colour, that lightens towards the belly. It has unique asymmetrical colouring on the head, which may be related to feeding habits. Its blow is a single thin column between 6 and 12 metres high.

Distribution and habitat

Humpback whales may be spotted from the shore off the Northern Kwazulu-Natal coastline. The population whose migratory route passes close inshore of the northerly South African east coast was decimated by whaling operations, that thankfully ceased in the 1960’s. Studies by South African researchers show that the population has since increased substantially.

General behaviour

Humpbacks apparently produce the longest and most varied songs in the animal world, that range from high frequency whistles to low rumbles. Analysis of their sound emanations that can include grunts, moans, moos, rasps and twitters shows that these sounds are organised sequences that last about 10 minutes and which may be repeated over and over again. Apparently these arranged sequences of various sound combinations are population specific, so that all the Humpbacks in one area will sing only the local song.

Conservation

Commercialised whaling has had a tragic and devastating effect on the Humpback population – estimated original populations of hundreds of thousands were reduced to some 2 000 in the Northern Hemisphere and even fewer in the south. Today, the world population is estimated at around 6 000.

Text by Derek Ohland