Krill are shrimp-like ocean creatures that grow to 2-3” long. They are one of the most abundant animals in the world, representing 500,000,000 tons of biomass worldwide (about half that of humans). They are a critically important food source for fish, squid, seabirds (including penguins) and whales. About half of the world’s krill end up as food for other creatures.

In the past two decades, commercial harvesting of krill has grown dramatically. Krill are harvested for use in food supplements and as feed for farmed fish. Efforts are underway to develop food products for human consumption using krill as a base.

It takes 2-3 years for a newly hatched egg to develop into a sexually mature adult. In one species of krill endemic to Antarctica, Euphausis superba, the female can lay clutches of a thousand eggs several times a year. The eggs are fertilized externally by the male and then fall to the bottom of the ocean. After the eggs hatch the young go through a several-step process of transformation and eventually return to the surface of the ocean.  At the surface, they feed upon algae growing on the underside of sea ice. The amount of sea ice is diminishing around the world and as a consequence, krill are having greater difficulty finding food. It is expected that sea ice in the north polar region will practically disappear in years to come and when it does the remaining ice in Antarctica will become the sole remaining feeding area for krill. 

Some efforts are underway to bring together marine regulatory agencies in countries that have interests in harvesting krill to coordinate efforts to preserve krill populations. There is a need for research to better understand the role of krill in marine ecosystems and to establish guidelines for harvesting to insure the long term sustainability of these unique organisms.