Estimates of bacterial production and activity, and of planktonic community respiration, were made at a series of stations starting in an estuary, passing through the coastal front, and across the continental shelf to a distance of 120 km offshore in the Georgia Bight. Measurements were made on unfiltercd and on 1.0 pm (pore-size) filtered water samples to examine the small free-living bacterial size fraction relative to the larger plankton. In waters landward of the coastal front, ca 50 to 80'70 of bacterial and community activity was associated with the larger size fraction, indicating the importance of larger and particle-associated heterotrophs in the nearshore, hghly turbid water. Seaward of the front, 80 to 99 U/o of activity was in the C 1.0 pm fraction. Thus, the < 1.0 pm size fraction is responsible for most of the respiration in shelf-waters. Bacterial production and activity decreased markedly with distance from shore; community respiration also decreased across the shelf, but not as much as the bactclrial production decreased. Bacterial growth efficiency was low in estuarine waters (11 %), and decreased in nearshore (6 40) and shelf (2 %) waters.