Mammalian Biology 77 (2012) 90–96 Contents lists available at SciVerse ScienceDirect Mammalian Biology journal homepage: www.elsevier.de/mambio Original Investigation Vulnerability of small and medium-sized prey mammals in relation to their habitat preferences, age classes and locomotion types in the temperate Monte Desert, Argentina Solana Tabeni a,∗ , Natalia Marcos a,b , María I. Rosi b , Benjamin Bender c a Instituto Argentino de Investigaciones de las Zonas Aridas (IADIZA), Grupo de Investigaciones de la Biodiversidad, Centro Científico Tecnológico (CCT) CONICET MENDOZA, Av. A. Ruiz Leal s/n, Parque General San Martín, Mendoza, CP 5500, CC 507, Argentina b Instituto Argentino de Investigaciones de las Zonas Aridas (IADIZA), Grupo de Ecología y Manejo de Vertebrados Silvestres, Centro Científico Tecnológico (CCT) CONICET MENDOZA, Av. A. Ruiz Leal s/n, Parque General San Martín, Mendoza, CP 5500, CC 507, Argentina c Museo de Ciencias Naturales José Lorca, LAE, Universidad Nacional de Cuyo, Av. San Francisco de Asís s/n, Parque General San Martín, Mendoza, CP 5500, Argentina article info Article history: Received 6 March 2011 Accepted 22 September 2011 Keywords: Arid lands Prey preference Risk of predation Rodents Small felids abstract In this study we examined predation by small felids upon small and medium-sized prey mammals in the central region of the Monte Desert. We analyzed the degree of vulnerability of prey mammals in relation to their habitat use patterns, modes of locomotion and age classes. Medium and small rodents were the predominant prey in the diet of small cats. The most consumed small mammal was Akodon molinae, which inhabits areas of dense cover, while species occurring in open habitats such as Eligmodontia typus were less consumed. Among medium-sized mammals, Galea leucoblephara that depends on patches with high plant cover for refuge was more consumed than Microcavia australis that lives in colonies and displays a complex set of antipredator strategies. Prey selectivity on small rodents showed that E. typus, which uses bipedal locomotion and an erratic escape behaviour, was consumed in greater proportion than its availability. We suggest that although its specialized locomotory mode would diminish predator attacks, its preference for open habitats would increase the probability of predator–prey encounter. Consumption of small mammals focuses mostly on adult individuals. However, we found a significant consumption of senile individuals of A. molinae, which points out that vulnerability tends to be high towards the age of maturity in this species. © 2011 Deutsche Gesellschaft für Säugetierkunde. Published by Elsevier GmbH. All rights reserved. Introduction The patchy structure of a desert, with sparse plant cover inter- spersed between areas of bare soil, involves a high cost to small or medium-sized mammals moving between patches (Shenbrot et al. 1999). Prey vulnerability may be reflected in the predator’s diet selec- tion and composition. Also the selection of prey species may reflect seasonal changes in their abundance, in response to resource pulses typical of deserts, or daily changes, e.g. levels of activity in rela- tion to moonlight (Leaver and Daly 2003). The prey consumed may also show the time of greatest vulnerability of the population and the most susceptible age classes (offspring, juveniles, or adults) (Longland and Jenkins 1987). ∗ Corresponding author. Tel.: +54 261 5244144; fax: +54 261 5244001. E-mail addresses: stabeni@mendoza-conicet.gob.ar, mariatabeni@hotmail.com (S. Tabeni). Vulnerability to predation has been analyzed in relation to various factors, among others the patterns of habitat use, morpho- logical and functional strategies to avoid predators, and foraging behaviour (Kotler 1984; Creel and Christianson 2007). Among the foraging strategies that reduce predation risk is that of some small mammals of North American deserts which may forage closer to plant cover in safe microhabitats (Kotler et al. 1991, 1994). Oth- ers like the widely studied heteromyids, kangaroo rats (Dipodomys spp.), have cheek pouches that allow transport of seeds to safe places (Brown and Lieberman 1973; Daly et al. 1992; Leaver and Daly 1998). Vulnerability may be lower in species exhibiting bipedal locomotion. Bipedality permits more rapid acceleration, a faster response to predator attacks and sudden changes of direction (Kotler 1984). Among South American arid lands, the Monte Desert consti- tutes the most arid rangeland of Argentina (Abraham et al. 2009). The vegetation of this biome is heterogeneous at every scale from regional to within-patch scale (Bisigato et al. 2009) and forms a mosaic of patches with different conditions of shelter, food availability and types of substrate that influence the modes of 1616-5047/$ – see front matter © 2011 Deutsche Gesellschaft für Säugetierkunde. Published by Elsevier GmbH. All rights reserved. doi:10.1016/j.mambio.2011.09.006