Page 77 - KBHA BULLETIN 4

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When they are too hot they will do a bit of sailing, they drop their heads down and float along

with the current leaving their tail up in the air. Whales have an extremely good blood supply in
their tails and by doing this they cool themselves off.

They swim at a leisurely pace of about 6 km an hour but can reach up to 11 km an hour -

especially when on their way to Antarctica where they find their food supply. These whales eat
for only 4 months of the year and for the rest of the time they do not eat at all. When they are in

the krill fields in Antarctica getting their annual food supply, they plough through the krill-laden

water with their mouths open. The krill and water flow into the mouth and are caught up in the
fringes inside the mouth. When their mouths are full they will close off their throat which is only

about 30 cm across, and as they close their mouth the water then flows out through the plates at

the bottom of the mouth and they then swallow the mouthful of food.

Depending on their size they will eat between 600 kg to 1,5 tons of krill per day. Whales have
four stomachs. There are two main stomachs. The first one acts like the crop of a fowl and the

second stomach has the gastric juices which then start to break down the krill. The whales have
to build up a layer of blubber of at least 30 cm thick so that they will be able to survive during

the time when they do not get any food at all.

Whales communicate under the water with one another by grunting and groaning. These noises

travel quite far. The 30 metre long Blue whale can be heard over 100 miles away. A Killer whale
pod sounds like a farmyard and the Humpback male can sing continuously for several hours.

Whales in False Bay today

The reason why whales come to False Bay is that it is far too cold for them to calve in Antarctica
so they come to the bays in South Africa where the waters are warm and safe with lovely sand

bottoms. They calve between Plettenberg Bay and False Bay. The cows start arriving in late June
to give birth to their calves which they have carried for a year. The peak period for calving is

between late August to mid-September. The calves weigh about 1,5 tons and are about 5 metres

in length at birth. The teats are situated on either side of the genital slit underneath the body.

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