Fact File
Humpback Whale Megaptera Novangliae
Identification made easy: Look for a stocky body, grey to black
in colour, with a white underside. Raised ‘knobs’
are apparent around the head area. The pectoral fins are up to
1/3 of the body length, often white in colour, and
serrated along the leading edge, as are the tail flukes along
the trailing edge. The dorsal fin ranges from no more
than a slightly raised hump, to a triangular or falcate fin.
Barnacles and whale lice are found around the head and
mouth. Length: Average 13-14 metres, but up to 19 metres. Females
are slightly longer than males.
Length at birth: 4-5 metres.
Weight: Average 22-36 tonnes, but up to 48 tonnes.
Baleen: 270-400 plates on either side of the upper jaw,
reaching lengths of up to 80 cm.
Ventral grooves: Usually 14-22.
Also known as: buckelwal, pflockfish, knurrwhal (German);
bultrug (Dutch); pukkelhval (Danish); knölval,
puckelval (Swedish); knolhval (Norwegian); gorback (Russian);
baleine à bosse, baleine à taquet, jubarte,
mégaptère, rorqual à bosse, rorqual du cap
(French); megattera (Italian); yubarta, ballena jorobada, gubarte,
jorobada, rorcual jorobado (Spanish); jubarte (Portuguese); kampouira
phalaina (Greek); zatokuzira (Japanese);
aghvesiiq (Yupik); muc-mhara-crotach (Gaelic).
Family: Balaenopteridae.
Diet: Mainly krill in the Southern Hemisphere, but also
(especially in the Northern Hemisphere) crustaceans,
sardines, anchovies, mackerel, and other small schooling fishes.
Habitat: Found virtually worldwide, but with apparent
geographical segregation between at least ten populations.
Although some mixing does occur between these populations, there
has probably never been any contact between
the populations from the Northern and Southern Hemispheres. Humpback
whales are strongly migratory,
seasonally migrating from polar feeding grounds to warm temperate
or tropical breeding grounds.
Group size: Usually found alone or in groups of 2-3, but
larger aggregations are found at the feeding grounds.
Sexual maturity: 4-6 years.
Physical maturity: 14-16 years.
Gestation: 11-12 months.
Lactation: 5-12 months.
Reproduction: The calving interval is usually 2-3 years,
however, several female humpback whales in the North
Pacific have been known to produce calves every year over three
consecutive years. Calving usually occurs in
winter.
Longevity: The lifespan of humpback whales is estimated
to be 40-95 years.
Did you know ….
? The humpback whale was first described in 1781 by Borowski.
? The humpback whale is classified by the IUCN (The World
Conservation Union) Red List as ‘Vulnerable’.
? The IWC (International Whaling Commission) gave humpback
whales worldwide protection in 1966.
? The global population of humpback whales is estimated
to be approximately 10,000. The original world
population is estimated to be approximately 115,000.
? The humpback whale is the fourth most numerically depleted
large cetacean worldwide.
? Humpback whales pass by New Zealand on their way to
their Antarctic feeding grounds from late August
through to early December, then again heading north to their
South Pacific breeding grounds through the autumn
months.
? Humpback whales are the slowest rorqual, cruising at
speeds of only 4-14 km/h, but may attain speeds of up to
27 km/h.
? Dives usually last 3-9 minutes, but may last up to 45
minutes. They do not generally dive deeper than 120-150
metres.
? The genus ‘Megaptera’ means great wings.
? During breeding season, the male humpback whales are
known for singing the longest and most complex songs in
the animal kingdom. A typical song lasts from 10-20 minutes,
is repeated continuously for hours at a time, and
changes gradually from year to year. All the males of the same
population sing almost the same song each year.
Humpback whales have been observed using a technique called ‘bubble
netting’ to capture small schooling fishes.
The whale circles below a school of fish, releasing a steady
stream of bubbles, which encircle the fish and trap
them. Up to 24 whales may work co-operatively using this technique.
Material on this page has been made available to us by Project Jonah
Whale Rescue Inc.
Additional information..... http://www.whalerescue.co.nz/text/resources_fact_hump.html
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