The present work analyses the abundance and species composition of mesozooplankton in relation to different patterns of wind speed and tides in Admiralty Bay. The plankton was sampled on 12, 13 and 15 March 1989 with a 385 μm mesh size conical-cylindrical net by R.V. “Barao de Teffe”. In Martel Inlet, the zooplankton standing stock reached 25,223 individuals 100 m−3 during the high tide. Under north-west winds, the abundance of the dominant species Ctenocalanus citer and Fritillaria borealis followed the tidal cycle. Weak south-west winds promoted the input of plankton even during low tide. Throughout the Bay, the highest densities of plankton (446–2,899 individuals 100 m−3) were observed in surface waters flowing towards the Bransfield Strait. Surface waters flowing through the Bay and the inlets showed different species composition to surface waters flowing towards the Bransfield Strait.