Unsynchronised and synchronised vertical migration of zooplankton in a high Arctic fjord

We measured vertical migration of zooplankton in an arctic fjord at 79°N between June and September 2002 and transcending a period of continuous illumination to one of true day and night to investigate the changing influence of light cues on behavior. Observations made with a moored 300 kHz acoustic Doppler current profiler indicated that two modes of vertical migration occurred during the study period. During the weeks of continuous...