Tuesday, May 27, 2014

In Search of...Water

"Wish you were here."

Another beautiful morning off the coast of Oregon.  The plan for today: search for water the is high in phytoplankton biomass and low in pH.  To do this, the iron fish was deployed over the starboard side of the R/V Melville.  At this stage in the cruise, deploying equipment over the side has become routine.  Once the fish was deployed, the R/V Melville sailed slowly, allowing the fish to pump water onboard. As the water reaches the lab, it is immediately checked for nutrients, pH, and iron concentration.  We are expecting water that is high in phytoplankton biomass and low in pH.  By analyzing the nutrients in the water, we can determine of the phytoplankton has taken them in.  If the nutrient levels are low, that could possibly mean that they have taken in their "food," and that their early stages of growth have passed.  So as the day carried on, so did the "fishing." When Dr. Wells walks through the lab and says "fish time," we know it's time to grab a life vest and helmet.  We are proud to get dirty and wet.

The iron fish.
To deploy the fish, we need at least five people on deck, and one person (from the R/V Melville, operating the ship's boom). The restech, Keith Shadle, communicates with boom operator and the bridge by using hand signals and a radio.  Dr. Wells and I lower the fish over the side, hand over hand.(which is a difficult task due to the drag caused by the currents).  Dr. Wells enjoys yelling "shoulder workout" as we let out the line. The fish is a hosed-vane, that pumps water back to the ship.  Keeping the fish vertical, is a weight that resembles a torpedo, and hangs below the vane.  It's very heavy and awkward to handle, especially when the ship is tossing.  Two other people on deck serve as our safeties, holding onto the line in case one of us slips, and lose grip of the fish. When the time comes to retrieve the fish, we end up wet and smelling like...fish.  

The fish is towed alongside
the R/V Melville.  The white hose
carries water onto the ship's lab.
As the R/V Melville  searched for the right kind of water, we got caught up on things inside the lab.  I read chlophyll samples in the dark room while Trey filtered samples for Brian Bill's domoic acid experiment.  We also took samples from the "Terminator," a large incubator that allows us to continually culture phytoplankton on deck.  Unlike the other incubators in which the sampled water is kept within bottles, the water in the Terminator is free to move around.  The capsules inside rock back and forth to continually agitate the cultured cells with water pumped in, maintaining a constant temperature.  I enjoy filtering and processing these samples because it gives me an opportunity to see how quickly phytoplankton can grow.   Next time someone says something to you about seawater being green, tell them it's a good thing--it's algae!

Dr, Wells, Dr. Trick, Dr. Cochlan, and Dr. Trainer.
Other than sampling, we used today to calibrate our gauges and equipment.   The PIs spent most of late afternoon up until suppertime to decide what to do next.  We were not able to find the water we needed.  Instead, we were in water that was moderate in phytoplankton biomass and at a slightly higher pH than we wanted.   Trey and I ended the day by preparing for tomorrow and getting caught up on our blog writing.  The Internet out here has been slow and spotty at times, which makes writing in between sampling a challenge.   

Getting work done before the end of the evening.
We are currently steaming north at full speed toward Cape Kiwanda.  Unlike other nights, the sea is calm, making our transit so far, very smooth.  After breakfast, we will once again deploy the fish to survey for the water we are looking for  We will also sample all of our cultures, break down experiments and plan to start all over again for one more experimental run before reaching Seattle.   Tomorrow is going to be a long day.  We are ready!  

Happy birthday Rachel Carson.
 Working at sea - in your memory.
A view of the Terminator.

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