SIGNIFICANCE OF COPEPOD EMERGENCE OF BENTHIC, PELAGIC, AND PHYTAL LINKAGES IN A SUBTIDAL SEAGRASS BED

The role of meiobenthic copepod emergence in linkages among benthic, p elagic, and phytal habitats was examined in a subtidal seagrass (Thala ssia testudinum) bed at the mouth of Tampa Bay, Florida, USA. On 4 dat es the ability of emerging copepods to affect the density and composit ion of benthic and phytal assemblages was tested during 2 h periods of minimum and maximum emergence. Copepod exchanges between benthic and phytal habitats and the duration of pelagic excursions also were exami ned throughout a night by measuring settlement into 2 types of sedimen t traps and onto natural and defaunated seagrass blades. The ability o f emerging fauna to disperse through the water column was determined f rom horizontal collectors. Changes in copepod densities and compositio n during periods of active emergence did not indicate an unequivocal e xchange between sediment and seagrass blade assemblages. Copepod reset tlement onto the sediments was greater during periods of increased eme rgence and suggested that emerging copepods typically did not remain i n the water column for a prolonged (> 2 h) time. The dispersal of cope pods through the water column was haphazard and unaffected by prevaili ng currents. Species and habitat affiliation influenced both the dispe rsal and settlement behaviors of emerging copepods. Although appreciab le numbers of sediment-associated copepods can enter and disperse thro ugh the water column, our results suggest that the effects of emergenc e on linkages between benthic, pelagic, and phytal habitats are minima l or limited in duration.