What are Krill? The Most Abundant Animal on Earth

Euphasia superba
What are Krill? (Euphasia superba)photo from Wikipedia

Or specifically, one of the creatures with the most biomass on Earth (we don’t know for sure though as so much is being harvested by humans or eaten by animals). That would be krill, the small shrimp-like creatures that large whales love to gobble down.

My name is Karl, and I am a krill. I live in Antarctic waters. What is it like to be part of a collective or large group? Well, not only am I small at 2.4 inches or 6cm long, but I live in a swarm of krill. A swarm may be as dense as 10,000 individuals per cubic meter and may stretch for many kilometers. There are 82 kinds of species.

The total biomass, or the total weight of krill is estimated at 379 million tons.
Half of that is eaten by animals such as whales, seals, penguins, squid and fish each year! Blue whales eat 4 tons of us a day! So my life expectancy is less than a year unless I’m lucky and can live up to 5 years. That is if I don’t get caught by a krill fishery either. Krill is used in supplements, aquaculture, aquarium trade, as bait and as food for humans in places such as Japan and Russia.

As a wee lad, I ate microscopic food stuck to the ice. I also depended on the ice for shelter from predators. Climate change is causing the sea ice to melt earlier in the season, and this is a problem for young krill. Some populations have declined up to 80% due to climate change.

Let’s hope climate change doesn’t wipe out my species, as it would be detrimental to animals higher on the food chain like whales and seals.

Also see Krill guide: what they are, and why they are so important

and
Prochlorococcus (Blue-Green Bacteria) are the Earth’s Most Abundant Photosynthesizing Biomass