Changes in copepod distributions associated with increased turbulence fromwind stress

Vertical profiles of turbulent kinetic energy dissipation rate (epsilon), c urrent velocity, temperature, salinity, chlorophyll fluorescence, and copep ods were sampled for 4 d at an anchor station on the southern flank of Geor ges Bank when the water column was stratified in early June 1995. Copepodit e stages of Temora spp., Oithona spp., Pseudocalanus spp., and Calanus finm archicus, and all of their naupliar stages except for Temora spp., were fou nd deeper in the water column when turbulent dissipation rates in the surfa ce mixed layer increased in response to increasing wind stress. Taxa that i nitially occurred at the bottom of the surface mixed layer at 10 to 15 m de pth (epsilon less than or equal to 10(-8) W kg(-1)) before the wind event w ere located in the pycnocline at 20 to 25 m depth when dissipation rates at 10 m increased up to 10(-6) W kg(-1), Dissipation rates in the pycnocline were similar to those experienced at shallower depths before the wind event . After passage of the wind event and with relaxation of dissipation rates in the surface layer, all stages returned to prior depths above the pycnocl ine. Temora spp, nauplii did not change depth during this period. Our resul ts indicate that turbulence from a moderate wind event can influence the ve rtical distribution of copepods in the surface mixed layer. Changes in the vertical distribution of copepods can impact trophic interactions, and move ments related to turbulence would affect the application of turbulence theo ry to encounter and feeding rates.