At Sea with the Bold: Plankton Passion

Two staff members, Margot Perez-Sullivan and Margaret Ford, joined nine environmental scientists and the crew of EPA’s Ocean Survey Vessel (OSV) Bold to document science and research in action. Read the blog posts by Margot Perez-Sullivan from our San Francisco office to get an in-depth look at some of what’s involved in protecting our waters.

Day 4 (9.8.08):

This afternoon, Eugenia used her plankton sampler to take a deep water plankton sample. It’s exciting to have this kind of opportunity because Eugenia usually samples off piers. She’ll use this information to try to figure out plankton characteristics that can be tied to red tides and other bio-toxic occurrences that compromise our ability to each shell fish. VIDEO: See Eugenia sampling.

Photo of CTD instrument being deployed in the waterThe previous shift finished all the grabs, so my shift moved onto using the CTD, which stands for Conductivity, Temperature and Depth. Sieving for critters was fun yesterday, but I was excited to do something new. A CTD measures the water’s characteristics and will be used in conjunction with the other samples to determine how the HOODS site is performing and will give scientists a better idea of water quality in the area. The CTD is deployed off the side of the ship, dropped down — almost but not quite — to the ocean floor.

Photo of computer screensAs readings are taken continuously with depth, the information is displayed real time on a computer screen and saved in a computer file in the Data Acquisition Center (DAQ). Usually a scientist and a member of the tech crew monitors the data coming in to see any important features at a particular location and make sure the device is working.

Photo of CTD instrument being retrieved from the waterOur shift ended around 9:30. We were strictly on CTD sampling; this is by far the most nerve wracking process as two doors open and the CTD is deployed off the side of the ship – which leaves room for falling. I didn’t fall, but those who know me, are fully aware of my clumsiness on land. CTD samples aren’t hands-on the way sediment sampling and sieving samples are, but what’s really interesting is that we get the data on a computer in the Data Acquisition Center in real time and can be analyzed later.

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