Shorebirds ecology in coastal areas is strongly influenced by tides. Foraging profitability at main feeding areas decreases considerably at high tides, resulting in birds moving to look for alternative feeding areas and roosting places. In the present work 1 studied the spatial use of Punta Rasa area (Buenos Aires province, Argentina) by three shorebirds: Golden plover Pluvialis dominica, White-rumped sandpiper Calidris fuscicollis and Hudsonian godwit Limosa haemastica. Between October and November 1991 we made ground surveys at low and high tides, covering the different habitat used by shorebirds. Patterns of habitat use with low tide differed significantly from those with high tide. At low tide more than 80% of individuals of the three species were observed feeding at the intertidal flats of Samborombon bay. At high tides the three species congregated in high areas, segregating in the selection of roosting places. At the same time, the diversity and intensity of human activities that disturb shorebirds varied between habitats, being more important at marine beaches. I discuss the patterns of habitat use for the three shorebird species in relation to the human use of the area, proposing its relevance for the management of the area.