Phy-to-plankton

We study phytoplankton!  When you hear this, an image of Plankton from Sponge Bob may pop into your head:

Image credit: Sponge Bob’s artist.

But don’t think for a moment that stealing a crabby patty recipe is the extent of the plankter’s purpose of life. It gets much more riveting and exciting than that. The story of life in the ocean begins on the micron scale with strikingly beautiful phytoplankton. No, not fido-plankton. We’re talking gorgeous, sunlight-harvesting life forms!

Diatoms, a type of phytoplankton, are the base of the food chain here in the Ross Sea, Antarctica. While alive, they are collecting energy from the sun (which shines 24 hours a day in the Antarctic summer!), using it for photosynthesis, and creating organic compounds.  When phytoplankton are consumed, they are a source of energy for an amazing collection of organisms that live in this icy world.  Not only does their presence support the ocean’s food web, but they also play a global role in oceanic carbon export to bottom water. They are found living in salty channels (brine channels) of the ice at the surface, floating in the upper layers of the water column, and it turns out, they can be the primary component of the sediment as well.

Despite their huge role in the ecosystem, these single-celled, plant- like organisms are very small.  This makes fieldwork – to be frank – boring.  Typically, if the ship instrumentation tells us we have high fluorescence levels in the water, we get a happy rush, knowing there is likely a lot of phytoplankton in the water. We sample seawater from the CTD (contraption with bottles that is lowered into the water to collect at different depths), and filter away. A brown, stinky filter is the slightly anticlimactic result, and the pattern occurs day after day.

 

Best described as a very cold version of the movie Groundhog’s Day, where the main character wakes up every day to a very similar version of the previous, time here becomes a blur. The disappointment almost makes us wish we worked with charismatic mega fauna (like this beautiful Emperor Penguin who visited us the other day).

The visiting Emperor Penguin who posed for 10 minutes on the ice before jumping in for a swim. Photo credit: R. Dunbar.

But before we let our minds slip too far into this silliness, the monotony of phytoplankter harvesting is broken by Christina Riesselman, Golden Pancakes, and the Smith-MacIntyre Sediment Grab.

Dr. Riesselman, from University of Otago, has been collecting water, ice, and sediment samples for microscopy to identify the species of phytoplankton present. We were caught looking over her shoulder all the time with wide, bright eyes, and were invited to participate in the sampling of ice and sediment.

Image of pancake ice during a sampling trip on the zodiac. The brown color between pancakes is from all of the phytoplankton living in this ice. Photo credit: R. Dunbar.

Amanda and Christina look at some of the water from the sediment grab sample on deck. Photo credits: R. Stevens.

Jacob and Rachel sample the sediment. Photo credits: A. McLenon.

When we helped collect a sediment grab of what looked like clay completely void of structure or life, Dr. Riesselman assured us it was full of diatoms. When she placed the first slide on the microscope and brought it into focus, those of us in the room were amazed at the beauty and intact shapes of various diatoms. Some looked like sand dollars, some like pillboxes, all with detailed silicate “shells” that held together all the way to the bottom of the sea.  We have to say it was the highlight of the trip thus far.

Amanda looking into the microscope. Photo credit: R. Stevens.

Image of diatoms under the microscope.  Photo credits: C. Riesselman.

Sometimes we need to be reminded why we are out here- risking our lives and sanity in the name of science.  And why we love phytoplankton.

—Amanda and Rachel of the DiTullio Lab


PS Check out Andrew's blog post, on the RSMAS blog, to the Billfish Foundation:
http://www.rsmas.miami.edu/blog/2013/03/07/thanks-to-the-billfish-foundation-costa-del-mar-from-the-ross-sea-antarctica/ 

Total Insanity: Exercise at Sea

People who work on boats might say that you get enough of a workout just living and working on a boat. Keeping your balance as the boat pitches and heaves requires some legwork for sure. But lately we’ve been mostly in the ice and at times our research vessel, the Nathaniel B. Palmer, is so smooth on the water that it hardly feels like we are moving at all. Operating heavy machinery and manually working on the boat could keep us strong, but most of us don’t. Instead we toil away in labs not very different from those we have at home. Occasionally we get to help out with deck work or even jump into a zodiac, but those experiences are true novelties. Our daily exercise is usually limited to lifting jugs and bottles of water. All that lifting is making my shoulders buff, but what about my cardio?

Cassandra filtering water for particulate organic carbon (POC), or “POC’ing” as she refers to it. Check out those guns! Photo credit: C. Riesselman.

Fortunately, we are surrounded with opportunities for staying fit. From the first day, the captain initiated a push-up tally sheet, encouraging everyone on board to participate so we could stay strong. We are supposed to do 25 push-ups each time a piece of scientific equipment goes in and comes out of the water. That’s 50 push-ups for every camera tow, net tow, or CTD (Conductivity, Temperature and Depth Recorder) we put in the water, all of which might collectively happen more than ten times a day. I vouched for five, rather than 25 but I still haven’t kept up.

Allison doing push-ups on the bridge. Some of the science crew need more motivation than others… Photo credit: C. Brooks.

On an average day I might make ten treks to the bridge, which entails climbing five flights of stairs. Other days I attempt to go for a walk, but confined by the ship, I don’t ever get very far. For those who like to run, we have a treadmill tucked away in an unused corner of the helicopter hanger. We also have a gym on board, fully equipped with an exercise bike, stairmaster and weights. When that isn’t enough, a small group of us engage in “Total Insanity” workouts, which entail 30-45 minutes of intense plyometrics that really get the blood pumping. But the most physically rewarding activity is when we have yoga classes in the third floor conference room, led by Amanda.

Cassandra running on the treadmill in the helicopter hanger (note the crew members working on the catwalk above). Photo credit: C. Riesselman.

Amanda adjusting Rachel during a yoga class in the third floor conference room. Photo credit: C. Brooks.

Antarctica is a world of extremes; it’s the coldest, windiest and most remote place on Earth. We work seven long days a week: science doesn’t sleep. Surrounded by superlatives, there is comfort in a ritual of daily exercise. It grounds us and reminds us how simply human we are.

View from the front of the Nathaniel B. Palmer – penguins on the left! Photo credit: C. Brooks.

—Cassandra