The role of Magellanic penguins (Spheniscus magellanicus) on landscape dynamics and lithic taphonomy in La Pastosa Islet, North Patagonia, Argentina

Abstract

This study presents the results of a systematic survey of La Pastosa Islet, located 700 m off the west coast of Río Negro, Argentina. This small islet has the particularity of hosting the northernmost colony of Magellanic penguins ( Spheniscus magellanicus) to date and contains evidence of its use by hunter-gatherer groups during the late Holocene. This growing colony started around 2002 and has had a significant impact on the subsurface archeological record of the islet by increasing erosion and exposing buried materials through nest excavation, particularly lithic artifacts. The spatial analysis of the distribution of artifact and penguin burrows indicates that the actions of the latter generated a “snapshot” of the subsurface distribution of the lithic record. The observed distribution suggested higher discard rates at the center of the islet. Furthermore, this study shows the synergy between both types of records in the formation dynamics of the lithic landscape and the agency of penguins as active landscape engineers. Finally, the obtained results have important implications for the management of the protected sector of the recently established Islote Lobos National Park, within which the study area is located.