Thursday, January 31, 2008

Day 10

Our noon position: Latitude: 32 46.18 North, Longitude 170 03.41 West

Skies are clear and sunny, but we were slamming along, receiving the ripples from a hurricane force low-pressure zone, far enough away for comfort, but noticeable nonetheless. Yesterday’s wildly celebratory mood has been considerably quieter, as crew retreated to their cabins, feeling the effects.

The afternoon lull was broken up by another sighting of a tangled rope mass. We dropped our drogue (an anchored buoy to mark our spot), and quickly lowered our sails as Joel and Jeff suited up with dive gear. Relocating piece of debris, with strong currents and winds blowing from all directions, has a needle in a haystick-like quality at times, but we managed to navigate back and find the floating culprit.

Though not as populated as our last rope mass, there was still a mini-ecosystem living underneath. The photo above shows a few pelagic fish hiding in the knots, and as we pulled the rope on board, dozens of fish and crabs came scuttling out. We scooped them up by hand and threw them in a mini aquarium, to observe and photograph before releasing them – here’s a close up of a crab. Can anyone out there ID this guy?

Plankton migration

Yesterday, we mentioned the huge difference between our samples from the morning and late afternoon/early evening. Our morning samples were mostly plastic fragments and some interesting ocean critters. The photo here shows one of our morning samples, with a mass of fish eggs entwined in some plastic fishing line. These eggs are a favorite food of the Black footed albatross and many of their boluses containing regurgitated fishing line can be found on Tern Island. Our evening sample resembled a gelatinous, orange-pink tinged mass, about the size of a baseball. This gooey mass is made up zooplankton, tiny, filter feeding organisms, coming up to the surface to feed.

During the day, millions of phytoplankton on the oceans surface convert solar energy into food, through photosynthesis. These Phytoplankton account for 98% of the oceans total biological productivity! As soon as the sun goes down, masses of zooplankton swim to the surface to feed on the phytoplankton, returning to the oceans depths at the first hint of sunrise.

This massive vertical migration happens across the entire ocean, every day -- the largest daily migration of any living organisms.

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