Bioluminescent plankton: Association with thin layers and marine snow in coastal oceans

Christy Herren, Ph.D.
MBARI

Wednesday, January 29, 2003
3:00 p.m. – Pacific Forum

Bioluminescent (BL) plankton can both deter grazing by small plankton and attract predators to those grazers. In this way, BL emissions may be a crucial mechanism for recruitment or dispersal of plankton from fine-scale structures, such as thin layers and marine snow. In my talk, the first quantitative esti-mates of BL marine snow over the whole water column in a coastal environment will be presented, and the ecological significance of these "islands of light" to the pelagic zone will 
be explored. For the first time, the composition, persistence, and thickness of BL thin layers (primarily composed of BL heterotrophic dinoflagellates in this study) have been documented in a coastal environment, using two newly developed instruments, the MBBP and the Mini-Splat camera.

My results suggest that plankton have more available niches than previously imagined in coastal environments, and argue the importance of accurately detecting fine-scale structures–not an easy job, even with emerging technologies. However, these "measurement-challenging" structures are already significantly altering our perception of oceanic food webs, biophysical coupling, and coastal carbon and nutrient cycling.