A time-lapse movie of the seabed at 710 m in the Florida Straits shows an irregular sequence of sediment ripple migration and suspension events, occuping 17% of the 43-day duration of the record. Sediment in the region is a moderately sorted carbonate medium sand. Simultaneous current meter records at various positions in and above the benthic boundary layer and are compared in various ways with the movie record to develop reliable predictive criteria for sediment motions in situ. With initiation and termination of sediment ripple migration predicted to occur when mean current at 3-m elevation is 24 and 22 cm/s, respectively 96% of the record is correctly predicted.