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SOUTHERN RIGHT WHALES (Eubalaena australis)
WHERE DO I FIND SOUTHERN RIGHT WHALES?
Southern right whales are migratory whales which travel between the Antarctic and the southern coastlines of South America,
Africa (South Africa) and Australia. They spend approximately half of the year (roughly December until May/June) in the
Antarctic region where feeding is their main objective. Following their time spent stocking up on food reserves, the
southern right whales migrate north between 3000-4000km to their mating and breeding grounds. These whales are most
commonly found just along the coastlines in South Africa between July and December.
WHAT DOES A SOUTHERN RIGHT WHALE LOOK LIKE?
Southern right whales are large black whales (some adults may reach between 14-16m in length) that can weigh between 40-70
tonnes. These whales lack a dorsal fin, unlike most large whales. One of the most distinguishing features of the southern
right whales is the scattering of "callosities" on their head. These callosities are simply rough patches of skin
on which barnacles and whale lice live. Each whale has a unique pattern of these callosities on their head, and the patterns
prove useful as mechanisms for individual identification (either visually or by examining photos).
When born, the southern right whale calves average between 4-6m in length, and 1 ton in weight. The whales have large square
-shaped black flippers and a large tail fin that can reach 5m in width. Approximately 4% of Southern right whales are born
mostly white in colour; this colour typically becomes a grey/brindle colour in adults.
When southern right whales are sighted, either at sea or from the coast, their identity is often facilitated by their "
V" shaped blow, due to the positioning of their two blowholes.
WHY ARE THEY CALLED RIGHT WHALES?
These whales got their name historically from early whalers, who determined that these were the "right whales" to
hunt, both for commercial value, but also for their ease of hunting. Southern right whales have a relatively slow average
swim speed (4-6km/hour), they tend to spend a significant amount of their time at the surface of the water, they would float
when dead and many of their calving and mating grounds are close to the coastlines.
Now they are considered the "right" whales to watch, again due to their fondness of the coastlines, and for their
slow swimming speeds.
WHY ARE SOUTHERN RIGHT WHALES ENDANGERED?
Because they were the right whales to catch, the Southern right whale population plunged significantly starting in the late
18th century, right into the 20th century. The whales were initially killed via traditional harpooning but whaling
modernized in the early 20th century and boasted steam powered boats with harpoon cannons, further facilitating the decline
of the whales. The Southern right whales becoming internationally protected in 1935, but numbers were at a drastic low prior
to this. In 1997 the South African population was estimated at 3100 whales, from a total of 7500 in the southern hemisphere,
still only thought to be about 10% of original numbers.
WHAT DO THEY EAT?
Feeding is only thought to occur while the whales are in the Antarctic region. The main food source for southern right whales
is small plankton called copepods. Although each copepod is very small in size, they tend to aggregate in dense groups in the
Antarctic waters, facilitating mass feeding opportunities for the whales. Southern right whales do not have teeth, but instead
have long baleen plates hanging down from their upper jaw (similar in theory to vertical blinds). They can have more than 200
of these baleen plates, which range in length up to over 2m. These baleen plates have a fringe of hairs running down their
sides. The whales swim into the swarms of plankton with the mouth open. To filter out the water they close their mouth, and
use their tongue to push the water between the hairy baleen plates (like a sieve), while still keeping the food in their
mouth. Feeding behaviour is rarely observed while in their mating grounds (with the exception of the nursing calves).
HOW LONG DO THEY LIVE?
Southern Right Whales are thought to be fairly long lived, up to 50 years, but possibly much longer.
HOW OFTEN DO THEY HAVE CALVES?
Most females have been observed to work on a 3 year cycle (one year of pregnancy, up to one year with the calf, and one
year to recover and rebuild food reserves in preparation of a new cycle). The calves nurse from the mother but it is
uncertain for how long this nursing lasts.
References
Best, P. 1997. Whale watching in South Africa. The Southern Right Whale. Marine Mammal Research Institute,
University of Pretoria, Pretoria. 2nd edition. 28pp.
Best, P. 2007. Whales and Dolphins of the Southern African Subregion. Cambridge University Press, Cambridge. 338pp.
© 2008 Dyer Island Conservation Trust
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Southern Right Whales often breach multiple times in a row |
Their tails can get up to 5m in width |
These whales have a very smooth back with
no dorsal fin |
A brindle Southern Right Whale putting its tail on display |
A rare close-up of the baleen plates
hanging down from the upper jaw in the mouth of a southern right whale. |
Small "spyhop" from a Southern Right Whale
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