Seasonal Flux and Assemblage Composition of Planktic Foraminifera from the Northern Gulf of Mexico, 2008-2009

The U.S. Geological Survey established a sediment trap in the northern Gulf of Mexico to collect time-series data on the flux and assemblage composition of live planktic foraminifers. This report provides an update of the 2008 time-series data to include results from 2009. Ten species, or varieties, of planktic foraminifers constitute >90 percent of the assemblage: Globigerinoides ruber (pink and white varieties), Gs. sacculifer, Globigerina calida, Globigerinella aequilateralis, Globorotalia menardii group, Gt. truncatulinoides, Pulleniatina spp., Orbulina universa, and Neogloboquadrina dutertrei. The mean daily flux is about 215 tests per square meter per day, with maximum fluxes of >800 tests per square meter per day during early February and minimum fluxes of