Behind the scenes

Dorado AUV targets chlorophyll layers to study plankton

Dorado AUV Canon

(top, from left to right): Bill Peterson (visiting scientist), Bob Vrijenhoek, John Ryan, Yanwu Zhang, Haibin Zhang (bottom) Julio Harvey (left) and Hans Thomas (right)

September 23, 2013

The Sampling and Identifying Marine Zooplankton (SIMZ) project of Senior Scientist Robert Vrijenhoek’s laboratory aims to further understand the ecology and genetic diversity of marine zooplankton. MBARI team members and outside collaborators sampled from the R/V Rachel Carson to target subsurface chlorophyll layers in northern Monterey Bay. Chlorophyll layers contain high densities of phytoplankton, organisms essential to the maintenance of the marine food web. The researchers used multiple sampling methods that week. One method involved deploying our Dorado autonomous underwater vehicle (AUV) using an algorithm (developed by Senior Research Specialist Yanwu Zhang and colleagues) to detect peaks in chlorophyll fluorescence and trigger water sampling from the layers of phytoplankton where grazing zooplankton also aggregate. Vrijenhoek’s team needed water samples to test the hypothesis that the plankton converge into patches that may be pushed shoreward. Samples were successfully collected by syringe-like water samplers in the AUV and are currently being processed. A second week of sampling is planned for October.