Dynamics of Protistan Grazers

Dynamics of protistan grazers: diversity, abundance and prey relations

Protists are important as both primary producers and consumers in aquatic microbial ecosystems. It is well established that protistan predation can be a significant source of mortality for bacteria and phytoplankton. Grazing protists in turn are a significant food resource for metazooplankton, and through the excretion of nitrogen and phosphorus compounds, they play a significant role in the release of regenerated nutrients. Despite decades of studies on protistan grazing, knowledge gaps exist with respect to their abundance, distribution, seasonality, prey selectivity, and co-occurrence patterns. This project builds upon an ongoing time series (with hourly resolution since 2006) by the Staining IFCB at the Martha’s Vineyard Coastal Observatory (MVCO) and will be the first to conduct long-term, high-resolution, automated measurements of grazer communities in situ to yield both morphologic and genetic information about the organisms present and their interactions with prey.