Antarctic Krill, Southern Ocean Swimmer

Antarctic krill is a small swimming crustacean in the Southern Ocean. It grows to 6 centimetres long.

Antarctic krill gather in swarms reaching densities of 10,000 to 30,000 per cubic metre. One swarm covered 450 square kilometers.

They shed their exoskeleton regularly to grow.

Six thoracopods form a feeding basket with openings only 1 micrometre wide.

Special rake-like setae scrape ice algae from the underside of pack ice. One krill clears a square foot every 10 minutes.

Bioluminescent organs on the eyestalk emit yellow-green light for up to 2 to 3 seconds. A built-in flashlight with a reflector.

The cumulative biomass of Antarctic krill reaches approximately 500 million metric tons. That is a lot of shrimp cocktail.

Crabeater seals eat over 63 million tonnes of krill yearly. Their multilobed teeth sieve it from water.