Program and Agenda

Abstract

PHYTOPLANKTON BIOMASS AND PRODUCTION, PHYSICAL DRIVERS AND POTENTIAL IMPACTS ON FISHERIES DURING SUMMER IN THE EASTERN BERING SEA

The timing and magnitude of primary productivity in subarctic ecosystems strongly influences the amount of energy that travels through the ecosystem. The timing of spring productivity (ice algae and phytoplankton) is related to sea ice coverage and retreat and set up of stratification, which in turn impacts zooplankton productivity on the eastern Bering Sea shelf. Summer and fall productivity and biomass, which sustains zooplankton and impacts food resources for fisheries, is related to stratification and wind events and subsequent surface nutrient fluxes. In late fall the reduction of light due to vertical mixing marks the end of the growing season. To assess the relationship between primary production, physical drivers and potential impacts on fisheries, we compare available summer phytoplankton biomass and production data, length of winter (period when phytoplankton prey are unavailable for secondary producers), summer stratification and wind events, nutrients, zooplankton abundance and age 0 pollock size and energy content over recent years (2003-2012). Results suggest that high summer stratification and few wind mixing events can lead to lower primary production, lower silicate and reduced size for age-0 pollock.

Authors

Eisner, L. B., NOAA/ Alaska Fisheries Science Center, USA, lisa.eisner@noaa.gov

Farley, E. V., NOAA/ Alaska Fisheries Science Center, USA, ed.farley@noaa.gov

Gann, J., NOAA/ Alaska Fisheries Science Center, USA, jeanette.gann@noaa.gov

Ladd, C., NOAA/ Pacific Marine Environmental Lab, USA, carol.ladd@noaa.gov

Mordy, C. W., NOAA/ Pacific Marine Environmental Lab, USA, calvin.w.mordy@noaa.gov

Details

Oral presentation

Session #:088
Date: 2/24/2014
Time: 14:30
Location: 316 B

Presentation is given by student: No