Tuesday, April 5, 2011

What does Antarctic phytoplankton look like?

Home in sunny California I had planned to keep this blog going and tell you all about our exciting findings back in the lab and while analyzing the data. However, of course, analyzing Antarctic data is far less exciting than gathering Antarctic data, so writing about it is less exciting too. I’ll try to keep writing about exciting bits and if you have any questions, please send them my way and I’d be happy to write about it. First, some things I still wanted to write about on the boat, but ran out of time. Antarctic Phytoplankton Soup (photo Dave Munroe) What does Antarctic phytoplankton look like? During the last weeks on the “NB Palmer” we got the camera on the microscope to work and were able to take some pictures of the algae we’re studying. Taking pictures of microscopic organisms on a vibrating ship is not ideal, so they are not the best pictures, but the phytoplankton are beautiful to look at nonetheless. It also makes the difference in sizes clear. What we see as green pea soup contains phytoplankton cells with relative size differences of a goldfish and a blue whale. And if you are a krill counting on phytoplankton for lunch, size matters. Some phytoplankton cells are too small to provide any nutrition, others are too big to take up. And some phytoplankton try to stick together in order to get too big to be eaten. So you will see diatoms in chains of up to 20 cells, making them much bigger. Phaeocystis, another abundant phytoplankton species, excretes gel to form a sort of balloon in which the tiny cells are embedded. In this way, a single species can span the relative size differences of the goldfish and the blue whale. Phaeocystis colonies. The green specs are the cells in the colony matrix, the biggest colony has a diameter of approx 3 mm.
Different chains of diatoms, the biggest cell has a diameter of aprox 0.05 mm (50 micrometer).The smallest dots are Phaeocystis cells (2-3 micrometer in diameter)
Cool diatom cells!