It is pretty amazing how a little creature like the krill (which only grows up to be about 6 cm long) can be so important for animals and humans alike. 

For the humans, their use is plenty; they can be used in fish feed, human dietary supplements (extremely rich in Omega-3 fatty acids), soya sauce flavouring, pharmaceuticals, and believe it or not, to clean the paintings of Old Masters.

In the Southern Ocean, they are part of a major food chain for animals such as seals, penguins and whales and snow petrels.

Stephen Nicol, a krill expert at the Australian Antarctic Division, said; "The krill catch is projected to go up with other countries getting involved. But there's a lot of concern because this is a keystone species - whales, penguins and seals depend on it. But part of that dependence is because there's a lot of krill."

The estimated Southern Ocean stock of Krill is anywhere from 100 million to 500 million tonnes.

Source:

The New Zealand Herald