A process study of krill behavior and physical fields in the Marguerite Bay region was conducted in the first cruise between April 23 and June 6, 2001 as part of the US GLOBEC Southern Ocean Project. The fields of temperature, salinity and currents were observed using a CTD and a 153 kHz Narrow Band Vessel Mounted Acoustic Doppler Current Profiler (VM-ADCP), and the krill distributions were observed using a Multiple Opening and Closing Nets and Environmental Sampling System (MOCNESS), an Optical Plankton Counter (OPC) and the VM-ADCP. Our study focuses on the relationship between physical fields, topographic features and krill distribution.