October 28: Krill!

Post by W&M undergraduate Domi Paxton.

Luckily, there was a break in the high winds and sea ice, so Kim and I were able to accomplish several things this past week! We were able to go out sampling a few times, allowing me to learn more about our equipment and earn some boating experience.

Antarctic krill Euphausia superba. Photo courtesy of Uwe Kils.
Antarctic krill Euphausia superba. Photo courtesy of Uwe Kils.

So far we have seen several krill aggregations on the echo sounder, and yesterday we were lucky enough to see the krill themselves swimming around under the brash ice! At the moment there are only juvenile Antarctic krill (Euphausia superba) in the area, but later on in the season we expect to see more of the large adults. Antarctic krill can live for 6-8 years and can grow up to 60 millimeters in length.

A group of scientists from the University of San Francisco studying phytoplankton, led by Dr. Deneb Karentz, actually caught some krill in one of their net tows and much to our appreciation, brought them back for us! We measured the krill lengths, which we then use with the acoustic data to calculate krill biomass and abundance. All of the krill measured were smaller than 20 millimeters, which means they are most likely a year old. We have also seen a lot of foraging activity from the penguins and seabirds in the area, it looks like it might be a good year for krill!

Author: David Malmquist

David Malmquist is the Director of Communications at the Virginia Institute of Marine Science, College of William and Mary.