August 19, 2006
Today was another beautiful sunny day with an almost flat sea surface. I went out onto the bow deck to take in the air and admire the view. The timing could not have been more perfect because at that very moment the lookout officer on the bridge called out "dolphins at the bow". Sure enough when I peered over the rail there they were, a pod of Atlantic Spotted dolphins, maybe a dozen in number, swimming both under the bow and near the side of the ship. Those at the side were jumping gracefully out of the water and the group at the bow appeared to be having fun trying to race the ship. However, the ship was traveling too slowly for them; they could easily swim at twice the speed we were traveling, so they soon tired of the racing game and after a few minutes they took off and disappeared from sight. I lingered at the bow a few more moments and I was glad I did, as just then I caught sight of several small objects leaping out of the water. They skimmed along the surface for a few seconds and then disappeared back into the sea again. It was flying fish! There must have been a bigger fish under the surface trying to catch them as jumping out of the water is a defense mechanism they use against predators.
Today I spoke with Don Cobb the scientist in charge of the EPA sampling work. The EPA survey was carried out at every fifth sampling site and involved obtaining and processing ocean water and sea floor sediments. The water samples were collected with Niskin bottles from the bottom, middle and surface of the ocean. The water samples were filtered and immediately analyzed for chlorophyll, nutrients (nitrates and phosphates) and dissolved solids. The sediment samples were obtained by a tool called a "Double Van Veen Grab Sampler", which is effectively a big claw. It was lowered to the ocean floor where it grabbed a bucket-sized sample of the sediment. A small sub-sample of the sediment was bottled for later analyses on shore where it would be tested for organic carbon, heavy metals and organic pollutants (such as oil, pesticides and PCBs) and classified according its grain size distribution (the relative proportions of mud, silt, clay and sand particles).
A second grab sample was obtained to determine what kind of creatures lived in the sediments. Processing this sample was another hose-intensive job as all the small clay and mud particles had to be removed by washing the sediment through a large sieve. Often this could take more than 30 minutes of hosing. The job was completed when only the larger particles and the creatures that lived in the sediment (mostly worms) were left on top of the sieve. These were bottled and preserved for analysis and identification at labs on shore.