SAILING: Whales are sometimes
seen to lift their tails out of the water for long periods.
HEAD: The head is large and
covered with wart-like bumps called callosities. These differ in
size and position and are often used to identify individuals.
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THE SOUTHERN RIGHT WHALE
was so named because it was considered to be the 'right'
whale to catch. Rich in oil and baleen (the large food
filter plates which hang from the roof of its mouth) and a
whale which floated in the water when killed, this
slow-moving leviathan became one of the most ruthlessly
hunted of all species of whales. 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 whales 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 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.
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. To hear a whale 'blow' is
like hearing the breath of life. The blow is a cloud of
vapour produced largely by condensation when warm breath
comes into contact with cooler air. It also contains oily
mucus from the respiratory tract of the whale. 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. 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.
Facts about
Whales
Colour black 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.
Length: 14 - 18 metres
Mass: 40 to 80 tons,
averages about 54
Cruising Speed: 5 - 8 km/h
or 2 - 3 knots
Gestation: About one year.
Calves 5 - 6 metres at birth. Growth rate about 3cm a day.
August is the best calving month. Pregnancy every 3 - 7
years. Lactation 4 - 8 months.
Longevity: Estimated to be
90 - 100 years.
WHALE COMPARISON CHART
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