Humpback Whale

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Humpback Whale by Sharon Salmi

Humpback Whale – Megaptera novaeangliae

Conservation Status: Endangered
Length: New-born calves 4 to 5 metres, Adult Females 11 to 15 metres, Adult Males 11 to 18 metres.
Weight: Birth weight is about 1 to 2 tonnes. Adults weigh up to 50 tonnes.

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Humpback’s love to breach

Breading
Humpbacks breed every 2 to 3 years. Mating and calving season in Australia is between June and October. Gestation lasts eleven months.  Birth weight is about 1 to 2 tonnes. They reach sexual maturity between 4 and 10 years of age and physical maturity between 12 and 15 years.

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A Humpback and calve

Diet / Feeding
Fish, krill and/or other crustaceans.
Humpbacks feed by taking a large mouthful of water and food such as Krill. They then push the water out of their mouths using their tongues. Their mouths contain baleen plates which filter out the food which can then be swallowed.

Humpbacks have also developed a unique way of working together to feed know as Bubble Feeding. To do this they deep dive together then swim back to the surface in a corkscrew pattern releasing bubbles as they do. The bubbles form a net that scares and concentrates the prey into a tight space which they can all take a huge mouthful of as they reach the surface.

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A Humpback Whale feeding by Teresa Byrne

Description
Humpbacks are one of the easiest species to identify. Their have the largest flippers of any of the whales reaching up to a third of their body length. They have unmistakable knobbly heads and throat grooves which expand when the whale is feeding. Individual Humpbacks also carry unique black and white markings on the underside of their fluke (tail).

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Humpback Calve

Field ID

  • Dark grey in colour with white markings
  • Very long pectoral fins with bumps along the leading edge – longest pec fins of all the whales
  • Bushy shaped blow from two blow holes
  • Small stubby dorsal fin two thirds of the way along their backs
  • Tail fluke markings and colour individual to each animal (like a human fingerprint) and used to identify each animal. May raise tail when deep diving
  • Slim head or rostrum covered knobs and throat groves underneath
  • Highly acrobatic – often seen breaching, slapping tail and pec fins, spy hopping
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A Humpback calve on the surface

Song
Humpbacks are famous for their songs. Only the males sing these long and complex songs that can last for hours and can be heard hundreds of kilometres away. Each population has its own distant song.

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A Humpback chin slap

Behaviour
Humpback whales are natural show-offs! They seem happy to entertain whale watchers by breaching; spy-hopping; lobtailing and flipper-slapping. Hardly surprising that humpbacks are the most popular whales on whale watch trips, and probably create more great photo opportunities than any other cetacean species. Their dives usually last less than 10 minutes but can be up to 45 minutes long. Males can be quite aggressive towards each other during the breeding season and they sometimes have scars on their skin from fighting.

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Humpback Breaching

Tail Fluke ID
Like a human finger print the patterns on the underside of the Humpbacks tail (or tail fluke) are unique to each animal, making them extremely useful in identifying and tracking individual animals.

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Individual Humpbacks can be identified by the marking on the underside of their tails which are unique to each animal.

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Individual Humpbacks can be identified by the marking on the underside of their tails which are unique to each animal.

Humpback Population Groups
World wide there are 14 distinct humpback population groups. Humpbacks are listed as endangered worldwide, with the Northwest Africa and Arabian Sea populations in particular trouble.

1. West Indies
2. Northwest Africa (Cape Verde Islands) – Endangered
3. Western North Pacific – Threatened
4. Hawaii
5. Mexico
6. Central America  – Threatened
7. Brazil
8. Southwest Africa (Gabon)
9. Southwest Africa (Madagascar)
10. Western Australia
11. Eastern Australia
12. Oceania
13. Southeastern Pacific
14. Arabian Sea – Endangered

Information NOAA Humpback Groups

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A Humpback calve comes to the surface

Migration
Humpback whales make some of the longest migrations of any animals from their feeding grounds (usually in cooler waters) to their breading grounds (usually in tropical waters). Humpbacks in Oceania migrate from their feeding grounds in the cold, rich waters of the Southern Ocean off Antarctica, to the warm tropical waters off northern Western Australia and Queensland in Australian waters and places like Tonga in Oceania to have their calves as the calves are born without the thick insulating bubbler layers to protect them from the cold. Over the breeding season the Humpback mothers use the time to train their calves to swim and to give them time to gain weight and the thick insulating bubbler layers so they will survive the return trip to the Southern Ocean.

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Humpback Migration Map by Garrettsen Eckerson

Humpbacks can swim at up too 8 kilometres per hour.
Humpback whales have been protected in Australian waters since 1965.

Humpbacks of the Northern Pacific travel between feeding grounds off Alaska to breed in the warm waters around Hawaii.

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Humpback Mother and Calve in Tonga

 

Information Source – NSW Government.