We just returned from our spring cruise to Dabob Bay in the state of Washington. The purpose of our cruise was to explore a hypothesis that has to do with the foraging behavior of zooplankton, the small (1-4 mm) animals that live in the sea. Every night they make a big trip to the surface waters from the deeper parts of the ocean to forage on plants (phytoplankton). Once there, do they eat, turn around, go back down? or: Do they eat and keep eating up in the surface waters? Our new imaging system is a bispectral (two wavelength) method which records not only the green reflected light from their outsides (carapace) but also their insides (the phytoplankton) that they ate that fluoresces in the red. Together, the green reflected light and the red light from their insides tells us which animals they are and how recently they ate. We spent about 8 days on the U. of Washington ship the Tommy Thompson in Dabob Bay and worked almost all night to see these little guys make a living. We returned, tired but happy with lots of great data that will help us try and unravel how these animals, probably the most numerous multicellular animal on the planet, make a living.
The goal of our most recent cruise was to deploy our FIDO vehicle in various configurations to observe particle size spectra and also time varying scatter of light in the ocean. Leaving from San Diego we over-nighted off Catalina (up and back) on the way to the Channel Islands. The cruise went extremely well. We profiled with the FIDO – PHI configuration for 4 nights and then switched over to observe time varying scatter by suspending a small disk from FIDO with the laser incident on it from one direction and the camera imaging from the other. We saw some amazing radial spokes of light emanating from the center of the scattered light patterns that we believe have never been seen before!!….What could they be from? We are currently figuring out what we got, what to do with it and what it will tell us about oceanic micro structure and the propagation of light the ocean. Stay tuned for more.
We now have a link to the Science article: “Swimming Against the Flow: A Mechanism of Zooplankton Aggregation”. Please refer to the Articles page for the link.
April 27, 2005 – The article on Fish T.V. will be appearing in the May 4th issue of Science.
Successful deployment of the Autonomous Underwater Explorer (AUE).
We just finished our third cruise with the 3dPIV system. We were planning on doing our tests up near Monterey, CA, but due to bad weather, we decided to stay around the Channel Islands. Despite the conditions, the 3dPIV operated reliably and we were able to get good data. Pictures of this cruise have been added to the 3dPIV page.
We just finished our second cruise with the 3dPIV system. The goal of this short cruise was to test the 3dPIV and to get practice launching and retrieving the system. Based on how well this cruise goes, we can do some more fine tuning to the system so that everything operates smoothly on the long cruise in September. Pictures of this cruise have been added to the 3dPIV page.