Spatial segregation among pampas deer and exotic ungulates: a comparative analysis at site and landscape scales

BILENCA D.; PEREZ CARUSI L.; BEADE M.

JOURNAL OF MAMMALOGY

ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS

Lugar: Lawrence; Año: 2017 vol. 98 p. 761 - 769

0022-2372

The pampas deer (Ozotoceros bezoarticus) is native to South America and is endangered in Argentina. In BuenosAires province, Argentina, the last population of pampas deer is harbored in the Bahía Samborombón WildlifeRefuge (BSWR), which includes protected areas and numerous cattle ranches. This population has been decliningand changing progressively in its distribution since 1985, and negative interactions between pampas deer andintroduced ungulates (livestock and feral pigs) have been proposed among the main causes of its decline. Weexamined the abundance, distribution, and interactions among pampas deer, cattle, and feral pigs at site andlandscape scales in the BSWR. At the site scale, coexistence between pampas deer and cattle at the same paddockwas only possible at moderate stocking rates (0.2?0.4 AU/ha), and no deer were recorded at paddocks whenstocking rates were above 0.6 AU/ha. Pampas deer and feral pigs co-occurred more frequently, but deer switchedtheir behavior and increased levels of surveillance in response to proximity of feral pigs. At the landscape scale, aclear spatial segregation and differential distribution was detected among pampas deer, cattle, and feral pigs alongthe BSWR. Our results suggest that the current distribution of pampas deer at the study area is a consequence ofavoiding contact with both livestock and feral pigs at the site scale. Thus, negative interactions recorded betweenpampas deer and introduced ungulates at the site scale were expressed at the landscape scale. Both in situ and exsitu conservation efforts are urgently needed to conserve pampas deer.