(PLEASE NOTE: These web pages are for archival purposes only and are no longer maintained. For current information on this topic at the AFSC visit the Ecosystem Monitoring and Assessment program. )

Zooplankton Composite (Photo by Angela Feldmann).

Zooplankton collected from oblique bongo tows in the eastern Bering Sea during BASIS surveys in late summer /early fall 2000-2004 were sorted and enumerated by staff from the Polish Plankton Sorting and Identification Center in Szczecin, Poland.

Contact:
Lisa Eisner
Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries

Ted Stevens Marine Research Institute
17109 Pt Lena Loop Rd
Juneau AK 99801
(907) 789-6602
Lisa.Eisner@noaa.gov

Zooplankton sample collection. Scientists conduct oblique bongo tows from bottom to surface using 505 mm and 305 mm mesh nets, then rinse nets into cod end, sieve, and preserve sample in 5% formula (photos by OCC staff).

Vertical tows from bottom to surface using a pairavet (left) or juday net (right) with 105 mm mesh allow us to collect smaller zooplankton than captured in bongo nets.

Calanus marshallae adult female (3.2-4.2mm)		Pseudocalanus sp. gravid female (0.7-2.0mm)
2004 Calanus marshallae Abundance (#/m3) from oblique bongo tow (505 cm mesh)		2004 Pseudocalanus sp. Abundance (#/m3) from oblique bongo tow (335 cm mesh)

For 2002-2004, small copepods were observed in the Inner Domain and Inner Front regions. However, large copepods were observed only in oceanic influenced waters on the southeast Bering Sea shelf, in areas with high surface nitrate inputs, and in the Anadyr Current, northwest of Saint Lawrence Island. Preliminary analysis indicates zooplankton biomass was low in Middle Domain regions. As a consequence, prey availability for forage fish and other higher trophic level consumers can vary dramatically across fronts over larger spatial gradients on the eastern Bering Sea shelf.