The objective of this paper is to provide new data about prehispanic occupations in the vicinity of the Sauce Grande shallow lake (Monte Hermoso, province of Buenos Aires). The results of the research about the Laguna Sauce Grande II and Laguna Sauce Grande III archaeological sites are presented. Furthermore, the subsistence, technology and mobility of hunter-gatherers during the late Holocene are discussed. In relation to subsistence, the abundant record of Amarilladesma mactroides (yellow clam) remains is a remarkable fact, which indicates that this bivalve was transported for 6 km from the Atlantic coast and used as foodstuff. The estimated size of the shells retrieved demonstrates homogeneity in selecting adult individuals. In regard to technology, 12 different rock varieties from diverse sources were identified, which means there were various transportation distance ranges involved. The artifacts were produced by knapping and by picking; those intended to resource processing are predominant. The material evidence, particularly that of archaeofaunae, presents novel information for the Pampean region. [ABSTRACT FROM AUTHOR]