| Southern
Right Whales. |
The SOUTHERN RIGHT WHALE has a circumpolar distribution and
inhabits sub antarctic water between about 30° and 55° south.
The whales migrate south during the summer months when supplies
of krill are more prolific, and north during winter and spring
to mate, calve and rear their young. They appear around the
South African coastline from May to December. They can be seen
interacting in the sheltered bays and coves close inshore and
near river mouths.
Today, the NORTHERN RIGHT WHALE is virtually extinct. In the
southern hemisphere populations show a slow increase since
international protection in 1935. There are estimated to be
about 3 000 - 4 000 SOUTHERN RIGHT WHALE at present, with South
Africa receiving the major percentage visiting its coasts
annually.
Present populations of SOUTHERN RIGHT WHALES are a fraction
of estimated initial stocks.
The SOUTHERN RIGHT WHALE can be distinguished from other
whales by its V-shaped 'blow' and the callosities which appear
on and around its head. Although many people mistake these
callosities for barnacles and although barnacles and other sea
life live on these patches on the whale's head, the callosities
are actual outgrowths of tough skin which form different
patterns on each individual and which are a useful form of
identification.
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| The
"blow" |
The
"blow" is a cloud of vapour produced largely by
condensation when warm breath comes into contact with cooler air
and drops of water from around the blowhole being forced up with
the rush of air as the whale breathes. It also contains oily
mucus from the respiratory tract of the whale.
As yet, knowledge about whales and the role they play in the
marine ecosystems is fragmentary. However initial benign
research indicates that whales are of greater benefit alive than
dead to man. For this reason, if for no other, they need our
protection.
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| COURTSHIP
AND MATING |
Courtship behaviour in whales can be very spectacular.
Displays of breaching and tail slapping are common, and the
whales touch each other frequently.
Courtship of a female whale may take many days. Mating
appears to occur in deeper water, and the females may mate with
more than one male.
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| PREGNANCY
AND BIRTH |
| After
a successful mating the female SOUTHERN RIGHT WHALE has a
gestation period of about 12 months.
The 5 - 6 metre calf is born tail-first, and is gently nudged
to the surface (often assisted by a 'midwife' whale) to take its
first breath. The calf will then find the mother's nipple and
she will squirt the milk into the calf's mouth.
The milk is very rich, and calves add 50kg per day to their
initial weight of 1000kg. At 10 to 12 months the calf is weaned
off its mother and will begin to eat small krill.
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| HOW
DO THEY BREATHE ? |
| As
we know, SOUTHERN RIGHT WHALES are mammals and so they need to
breathe air, unlike fish. The SOUTHERN RIGHT WHALE has two
nostrils or blowholes, fairly widely separated. This is the
reason for the distinctive 'V' shaped blow. When on the surface
whales breathe once every minute or so, for 5 to 10 minutes, and
then dive again. Up to 60 minutes below water has been recorded,
but this is unusual, and 10 to 20 minutes is more common. |
| WHALE
DESCRIPTION AND FACTS |
Black
Colour with occasional white markings along back and underside;
the body is stocky and fat, smoothly rotund without a trace of
dorsal fin or any ridge along the back.
The length varies between 14 and 18 metres, with a mass of 40
to 80 tons (average of 54).
The SOUTHERN RIGHT WHALE has a cruising speed of around 5 - 8
km/h or 2 - 3 knots and it's lifespan is estimated to be 90 -
100 years.
Whales are large brained and sensitive creatures. Strong
bonds exist between females and their calves. In normal
circumstances they are non-aggressive and gentle towards man.
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| Whale
Hotline |
People
can now phone from anywhere in the world to find out where the
whales are along our coast. The Whale Hotline's office is in
daily contact with all the information offices on the whale
route from Plettenberg Bay to Lambert's Bay.
The Hotline can be reach by phoning their toll-free number -
Tel 0800 228222.
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