Where do the whales go from here ?
Southern Right Whales travel between 2000 – 3000 kilometers from their sub-Antarctic feeding waters to South African breeding and mating waters each year. This migratory journey can take about six weeks.
From June until November – December Southern Right Whales can be found in South African waters and from January to May they are in the sub- Antarctic waters with some moving up the West Coast of Southern Africa.
These whales travel between 2000 – 3000 kilometers from their sub-Antarctic feeding waters to South African breeding and mating waters each year. This migratory journey can take about six weeks.
The mother will not commence on her migration unless she intuitively senses that the calf is fit for the journey.
FEEDING
Southern Right Whales feed entirely on zooplankton (Copepodas & Euphasiids ( Krill) )
Feeding takes place when the whales are in higher latitudes where the water is cooler and more biologically productive, such as the Antarctic and up the West Coast of Africa. They are not known to feed here but will take the opportunity if food is available.
Southern Right Whales are “skim feeders” meaning they feed by slowly swimming on the surface through swarms of small zooplankton with their mouths open, removing the krill from the water using their baleen. The krill gets trapped on the baleen plates and the whales flush the prey items out of the baleen before swallowing it.
Southern Right Whales need to feed on 600-1600kg of food daily to sustain themselves during their fasting period down in the southern African waters.
KRILL ( Euphausia superba)
Antarctic krill are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins – but they have another important role.
About 380 million tonnes of Antarctic krill call the Southern Ocean home, playing a vital role in carbon storage and nutrient distribution as it removes up to 12 billion tonnes of carbon from Earth’s atmosphere.
But Antarctic krill isn’t just whale food.
Most alarming are concerns about the future of krill in a rapidly changing climate. That’s a worry because of the many roles performed by krill.
For starters, it’s a core part of the diet of whales, seals, penguins, squid, and fish. But that’s the obvious bit. Beyond that, krill is a key component of what is known as the biological pump, which gets carbon dioxide out of the atmosphere and sequesters carbon at the bottom of the ocean.
It works like this:
Single-celled phytoplankton near the ocean’s surface take up carbon dioxide during photosynthesis and store the carbon. Then the krill eat the phytoplankton or other organisms that have consumed phytoplankton. So now the krill have the carbon.
Then comes the miracle of krill poo. It is particularly dense and heavy, and falls rapidly to the bottom of the ocean, taking tonnes of carbon with it.
Any carbon that the krill doesn’t excrete is likely to be taken up by its predators, such as whales, which also go to the bottom of the ocean where they die, sinking even more carbon.
Krill faeces account for the majority of sinking carbon particles found in both shallow and deep waters in the Southern Ocean.
“The Southern Ocean is one of the largest carbon sinks globally, so krill have an important influence on atmospheric carbon levels and therefore the global climate.”
It isn’t all about carbon sequestration either. Antarctic krill also distribute nutrients such as iron, both in their faecal pellets and when shedding their shells.
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