Satellite-tracked
drifting buoys are very useful for discerning ocean circulation patterns and transport.
FOCI's drifters are steered by ocean currents occurring at about the same
depth that larval pollock inhabit, ~40 meters. Thus they indicate
the trajectories that larval pollock patches might take. The figure
to the right displays trajectories of 91 drifters deployed from 1986 through
1999. Features to note are circular paths indicating eddies southwest
of Kodiak Island and transport off the shelf to the Alaskan Stream with some
subsequent recirculation onto the shelf. Animations
of these drifter trajectories are useful in determining interannual variability,
detecting eddies, and discovering currents. |