Krill Project

Post written by Charlie:



Tonight was not as eventful as other nights, but I did get to do a few things of note. Like yesterday I woke up in time to eat dinner. Again, like yesterday, after dinner I went up to the bridge deck to take in the nice day, only unlike yesterday, the weather was not so nice. In fact, it was downright chilly, so I didn't stay up there for very long at all. I then came down to the science labs and helped out Calvin a little more with the NAS, but there wasn't much to do so we finished up rather early. I was able to help out doing little odd tasks for my lab director, but nothing spectacular.

There were, however, a couple of cool things that I did get to do. It seems that the bird watcher guys found a real gem of a bird: the short tailed albatross. From hearing them excitedly talk about it, it is apparent that there are only a couple thousand left and to be able to see one at all is very fortunate. I got to see one. It pretty much flew in behind the ship and landed on the water and there it sat until we pulled too far away to see it anymore. I did get a decent look at it through some binoculars though and it was a fairly large darker colored bird. The bird watcher guys said that it was still a juvenile due to the darker colorings on it but they were very excited about the sighting since neither of them have ever seen one in all their years of bird watching. I was also able to watch the sunset out here. Sunset comes around one in the morning up here and I was able to take a couple of photos. It was very beautiful and slow, but didn't seem to be accompanied by very many colors like reds, purples or other ones, such as I would see back home. The waves are a little larger than yesterday though and looking down from the bridge deck it almost looked like the water had an almost leathery appearance to its surface. It was all very beautiful to witness. [Webmaster note: We haven't received any pictures from Charlie yet, so I have attached a picture that I took of a sunset in the Bering Sea aboard the Healy from June 2007 for you to get an idea of how beautiful it is. Hopefully the Healy 2008 cruisers will be able to send pictures soon.]

Other than that, we filtered some more sea water and did a few more odd things for the rest of the night. Near the end we were preparing to cut the eyes off some of the krill captured in our bongo net run the same evening. Perhaps I should explain just exactly why we're cutting the eyes from these krill. It's a little long winded but I'll try to summarize. Aging animals, such as crabs or krill, can be difficult as there are really no physical parts to their body to determine their age. The old way of aging them was to measure their shell, but that is often inaccurate because these animals often grow at different rates from each other. For example, you could have a runt of a crab and a huge crab and while they are the same age as each other, they grew differently, so we cannot accurately find their age by measuring their carapace (shell) length. Knowing the age structure of a krill population is very important for understanding how they live and grow, and how climate change might affect krill populations. As a dominant food source for higher trophic levels like whales, seals, etc., krill are small but important! Fortunately all of these animals make these chemicals called lipofucsins as a by-product of oxidative metabolism, by dissolving free radicals in the lysosomes of cells. These products accumulate in a roughly linear fashion per time, so by measuring how much of this lipofucsin has been produced and stored, we can figure out how old the krill was. Krill store these lipofucsins in the neural tissues of their eyestalks so we are able to pull out these lipids by cutting out their eyes and going in there to get them. Unfortunately the krill were still alive and were just not ready so we'll get to practice our cutting tomorrow night right after supper. As for me, it's been a long night and I'm pretty tired so I'll sign off for now. Stay tuned.