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Humpback
Whales |
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| Description |
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 The Humpback Whale
[Megaptera novaeangliae] is enormous, weighing up to 15 tonnes - about the same as that of 600 adult humans or 11 elephants. The average adult is 15m in length with a tail about 5m across.
Adult females can grow to 19 metres, slightly longer than adult males.
Baby whales are known as calves and are
approximately 4 metres and 680 kg
when born. The Humpback Whale is heavier, has larger flippers and is more solid than the other Baleen Whales found in the Southern Ocean.
They have an average swimming speed
of 7 km/hr. Humpbacks are generally black on the back with mottled black areas on its white underside, and numerous grooves under the flippers, although a white whale has been a welcome visitor to Hervey Bay for the past few years. |
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| Identification |
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| Each whale tail has a unique pattern like a human fingerprint and this is how researchers are able to identify them.
The tail fluke is utilised in
photo-identification. The patterned tail fluke underside
is individually unique as is the flank
pigmentation and to a lesser extent the dorsal fin shape. |
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| Communication |
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| Whilst all whales can emit sounds, the
humpback's sounds
which they use to communicate with one
another are unique. Some sounds form patterns known as whale songs. Humpback Whales are renowned for their melodious, song-like
call usually lasting less than 10 minutes, but can sometimes be repeated for hours. |
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| Feeding |
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| Humpbacks generally feed on krill (small shrimp-like planktonic crustaceans that drift in the ocean) and small fish like herring, but these are not caught randomly. The whales work in groups, and use plenty of noise, fin motions, and bubbles to scare the prey towards the water surface. There, the prey are trapped by these bubbles and the whales lunge up with their huge mouths open to engulf these schools of herring or krill. |
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| Numbers |
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| Once,
whales were killed for their oil, and
whale products were used for soap,
lubricants, polishes, margarines as well
as fertilisers and vitamins. They are fairly slow swimmers and made for easy targets by whale hunters especially in the 1800's where harpooning was common.
There were around 10,000 Humpback Whales off eastern Australia in 1952.
After just 10 years of commercial whaling, that number
was reduced to a critically low 100
whales. Hunting ceased in 1962 when the
whaling stations closed and today the east coast population is
increasing and estimated at around 4,000.
Even with the increase, worldwide there
are just 12,000 - about 8% of the original
150,000 Humpbacks. |
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