Herren, C, , Monterey Bay Aquarium Research Institute, Moss Landing, USA, herren@mbari.org
Haddock, S, , Monterey Bay Aquarium Research Institute, Moss Landing, USA, haddock@mbari.org
Brewster, J, , Monterey Bay Aquarium Research Institute, Moss Landing, USA, brjo@mbari.org
Case, J, , University of California Santa Barbara, Santa Barbara, USA, case@lifesci.ucsb.edu
Orrico, C, , University of California Santa Barbara, Santa Barbara, USA, orrico@lifesci.ucsb.edu

SLOW GLOWS AND FAST FLASHES: BIOLUMINESCENT SIGNALS AS INDICATORS OF PLANKTON COMMUNITY STRUCTURE

Although fluorometers can provide an estimate of phytoplankton abundance, there are few reliable ways to autonomously sample zooplankton populations. Existing optical and acoustic methods are limited in their ability to resolve species composition. Bioluminescence (BL), however, may be a means to rapidly sample and identify a fraction of the zooplankton population. When a plankter produces a BL display, the total intensity of light as well as the changes in intensity over time (or BL kinetics) are identifying parameters. Our goal is to develop a method for relating light measurements to plankton community composition and distribution. We studied plankton BL in Monterey Bay, CA, in December 2003 and March to April 2004. During these expeditions, we measured BL using high-resolution bathyphotometers deployed on a variety of platforms including an AUV and a towfish. Concurrent measurements of physical, chemical and optical seawater properties, as well as enumerations of both phytoplankton and zooplankton provide ancillary information for ground-truthing the BL data. Preliminary algorithms were developed that deconvolve the high-frequency signal into specific plankton concentrations by quantifying the individual flashes rather than interpreting the summed temporal bioluminescent signal over depth. We will provide examples of how we analyze these data and use them to better understand plankton population dynamics in Monterey Bay.