Conservation of the Pampas deer (Ozotoceros bezoarticus) in the semi-arid pasturelands of San Luis Province, Argentina: Relationships to land use practices

M. B. Semeñiuk
The Pampas deer is endemic to South America and has experienced a drastic reduction of its historical range. Since the 1990s, multiple techniques have been employed to improve livestock productivity in the region, leading to increased fragmentation of habitat types and the displacement of native plant species with exotics. The primary objective of this study was to evaluate the effects of these land use changes on the population dynamics and habitat use of pampas deer.
Using standard population surveys and behavioral observations, the researchers determined that in the study area, pampas deer abundance and distribution did not appear to be affected by increased livestock activity, suggesting that direct competition for space and food are not a conservation threat. More detailed study revealed deer grazing preferences for an exotic plant species with higher protein content and that allows patches of native grassland, as opposed to other exotic plant species with lower protein content and that create monocultures by dominating the landscape. Analyses also revealed that livestock may actually serve a similar function to natural fire regimes (now lacking on ranches), making young shoots more readily available to pampas deer. Careful and sustainable livestock practices, such as rotating grazing lands and keeping grazing pressure low, may actually help conserve deer populations in the limited areas where they still exist.
The study explored other potential threats to pampas deer, concluding that fences did not create habitat barriers as long as the dimensions allowed for passage; that water cisterns should be elevated to prevent drownings; and that livestock should be immunized to protect the health of deer as well. While the study concluded that current pampas deer populations do not appear to be negatively affected by grazing operations, they caution that there is still a need for enforcement against illegal hunting, signage to prevent road collisions, and outreach regarding best livestock management practices to accommodate long-term pampas deer survival. ($7,000)