What is your advice for students interested in a career in marine science?
If a student was interested in working with krill, or in the ocean they would need to:
- get an undergraduate degree in a biological science (Tracy has a degree in zoology);
- then obtain a masters degree in a marine science;
- volunteer work helps (As a student, Tracy worked as a volunteer in Antarctica); Volunteer work isn't always exciting, but it is the start to getting more and more responsibility.
- positive relationships with teachers: professors have lots of students. It is very helpful to have a good reference which means the professors need to know who you are.
Tracy believes that it was because of her Antarctic experience that she was hired for her current position. Her employer needed a person with experience working with live krill which she had done in Antarctica. Since Tracy had been a volunteer she not only got experience, but feels that she was chosen because of her experience. Any scientist will tell you that it is with experience and exposure that opens doors to careers in marine science.
Where do you study krill?
Tracy has studied in both the Arctic (Bering Sea) and Antarctic. She also studies off the Oregon Coast. Tracy goes to sea off the coast of Oregon every couple of weeks for a ten hour research trip. She also goes to sea one to two times a year on larger research vessels. There are also two Bering Sea trips a year: one for 40 days, and one for 30 days. It is hard being away from home for so long, but with internet even the longer trips are not so bad. Tracy works both in the lab and in the field. Being at sea is more of an adventure, but some lab work is very important so you can be ready to go to sea. When at sea you are 100% in a scientific world, your daily life revolves around what you are studying. When in the lab you still go home at night and do regular things.
Do you drill in ice or melt ice to get krill?
Krill are usually caught in nets, and the nets are typically towed behind the research vessels. It is difficult to collect krill from under the ice. Because ice freezes slowly krill are not trapped in the ice, but they do like to hang out underneath the ice. Under the ice there are algae (phytoplankton) which the krill like to eat. When you drill a hole in the ice, the krill move, which is why it is easier to catch them by pulling a net behind the ship as it breaks up the ice.
Are krill being affected by global climate change?
Scientists are studying krill right now, and they are starting to see that krill are possibly moving and found in different places as the temperatures of the oceans change. Some of the krill populations are getting greater and some are fewer, this is what scientists are studying. There are certain species of krill that have a narrow range of temperatures, if the water gets too warm or cold, the krill will move, and be in a new place that they possibly had not been in before. So, krill distribution is affected by the temperatures of the larger ocean.
What is the difference between krill and zooplankton?
"Most animals that are considered zooplankton have some ability to swim (copepods, jellies, etc.), but they are not strong enough swimmers to be in control of where they are in the water column. There is some debate about whether krill should truly be considered zooplankton, since the term suggests that they are being passively pushed around by the water when we know that they are able to swim down 100+ meters deep every day and back to the surface every night. Krill have five sets of swimming legs, called pleopods, and are pretty strong swimmers."
Are the Poles important ecosystems for krill?
Krill are found in the polar and temperate oceans, but not in tropical waters. They are very important to marine ecosystems, lots of animals eat krill. Pretty much everything in Antarctica eats krill. "Antarctica doesn't have large schools of pelagic fish like those found in the Arctic. In the Arctic, the schooling fish (like herring or pollock) eat the krill and the larger predators like seals, whales, etc. eat the fish. In the Antarctic the krill grow much larger than the Arctic krill and the penguins, seals, whales, etc. eat them directly. Antarctic krill (Euphausia superba) are easily twice the size of adult krill in any other ocean." "Krill are important in both the Arctic and Antarctic. Most higher trophic level predators in both ecosystems depend on krill, either directly (predator eats krill) or indirectly (predator eats something that eats krill). Both ecosystems have certain areas that are important to krill production, but you couldn't say that one is more important than the other. "