Prey availability for Puma concolor in three habitats of the Argentinian Espinal

LUCHERINI M.; LUENGOS VIDAL E.; SCARAVELLI D.; GUERISOLI M.; OLLA V.

Acquependente

Congreso; X Congresso Nazionale di Teriologia; 2016

ATIt

The puma Puma concolor is the top predator throughout most of the Americas, especially in the Southern Cone of the continent. Categorized by the IUCN as ?Least Concern?, is among the most widespread and adaptable felids. Nevertheless, habitat destruction and hunting has brought pumas to ecological extinction in vast regions of central Argentina. The Espinal is a mosaic of grasslands and shrublands that is heavily under pressure due to radical transformations of its natural habitats. Habitat loss due to agriculture and retaliatory killing for predation on livestock have caused a great reduction not only in puma populations but also in those of its native prey. The objective of this work is to evaluate the availability of the wild preys of pumas in the three main habitats of the Espinal: cropland, grasslandand, and shrubland.To estimate prey availability we performed line transects equally distributed among the three habitats. Transects were made during winter (78 transects, 1011 km) and summer (80 transects, 1028 km) of 2014. The prey species that we counted were: Lama guanicoe (90-140 kg), Rhea pennata (15-25 kg), Dolichotis patagonum (9-16 kg), Lepus europaeus (an introduced species, 1.5-6.5 kg), Eudromia elegans (0.4-0.9 kg), and Microcavia australis (0.2-0.5 kg). For each habitat and season, in addition to the number of individuals/km, we estimated an index of the total availability of prey biomass, multiplying the mean number of specimens recorded in transects by their average live body weight.Grassland showed the largest biomass in both seasons, with 13.6 and 12.4 kg/km in winter and summer, respectively; cropland presented a biomass of 11 and 9.4 kg/km and shrubland reached only 3.3 and 5.4 kg/km. Using parametric or non-parametric ANOVAs after normality and homogeny tests, we found a variation between the three habitat types only for the biomass of prey (Levene?s test, p < 0,05). No significant difference was detected for the number of individuals and season (Levene?s test p > 0,05). Shrubland represented the most divergent result, probably accentuated by a greater difficulty to spot small prey associated to its denser vegetation than in the other habitats. However, grassland was the only habitat with presence of L. guanicoe, an ungulate that is the preferred prey of pumas in this region. The scenario produced by our results opens new perspectives in the construction of a map of the priority habitats for the conservation of puma and their overlap with the human uses, which will help to predict areas of potential conflicts and design mitigation measures.