Isotopic Ecology in Modern and Holocene Populations of Pampas Deer (Ozotoceros bezoarticus) from Eastern Central Argentina. Implications for Conservation Biology and Ecological Models of Hunter-gatherer Subsistence

The Pampas deer (Ozotoceros bezoarticus) is an endangered ungulate from South American. The following paper presents the first investigation on the isotopic ecology (delta C-13(collagen); delta N-15(collagen)) of modern populations of Pampas deer. The information obtained is compared with new delta C-13 and delta N-15 data of Pampas deer bones recovered from archaeological sites in the Central Pampean Dunefields (Inland Pampa phytogeographic area) and with previously published archeofaunistic isotope data for sites from eastern central Argentina. The range of delta C-13 values of Pampas deer is broad, ranging from a diet dominated by C-3 plants to a mixed diet of C-3 and C-4 plants. The delta N-15 values mainly show distinct signals between the Atlantic coast and the interior. The diet breadth of the Pampas deer suggests a high adaptability to different environments, a crucial factor for conservation programs of this species. The delta C-13 values of the Inland Pampa do not show great differences between the Middle Holocene, Late Holocene and today. Adaptation strategies of the Pampas deer to the environmental changes during the Holocene were not associated with a modification of their feeding habits, but rather with social and demographic strategies. These variations in ecology conditioned the predictability of this prey for hunter-gatherers.