ARTICLES RIA / Vol. 43 / N.º 2 Carnivores in the southwest of the province of Buenos Aires: ecology and conflicts with farmers CARUSO, N.1,2; LUENGOS VIDAL, E.M.1,3; LUCHERINI, M.1,2; GUERISOLI, M.1,2; MARTINEZ, S.1; CASANAVE, E.B.1,3 ABSTRACT The key role that wild carnivores play in ecosystems is threatened by human persecution and habitat alte- ration worldwide. The SW region of the province of Buenos Aires, Argentina, is a region strongly modified by the spread of agriculture and where, in the last years, there has been an increase in carnivore predation on livestock. The simultaneous study of the ecology of carnivores and of their conflicts with ranching activities is essential to find solution that can minimize the impact of these species on the regional economy while main- taining their ecological role. We deployed camera traps in the Buenos Aires counties of Villarino and Patagones to study the factors affecting the distribution of the four most common species (puma, Puma concolor; Geoffroy’s cat, Leopardus geoffroyi; Pampas fox, Pseudalopex gymnocercus; Molina’s hog-nosed skunk, Conepatus chinga). Semi-struc- tured interviews to local ranchers and participative workshops were carried out to analyze human-carnivore conflicts. From 2008 to 2015, we surveyed 49 camera trap sites and characterized the study area through 12 variables related to anthropogenic alterations and to landscape composition and fragmentation. We also com- pleted 193 interviews and four workshops. For the interviews we used a questionnaire focused on collecting information on socio-economic aspects of ranchers and ranch management, while in the workshops we sear- ched for a common agreement on the relevance of the potential factors affecting human-carnivore conflicts. The application of Generalized Linear Models to camera trapping data indicated that the use of habitat by carnivores in the region is affected by the alterations of natural habitats. The Pampas fox and skunk were the species with greater adaptability, whereas the puma and Geoffroy’s cat appeared to be more sensitive to ecosystem modifications. Pumas avoided intensively modified sites and preferred natural patches. Losses on livestock by pumas and Pampas foxes during the previous year were reported by 47% and 55% of respon- dents, respectively, and 93% of ranchers considered carnivores as detrimental to regional production. Work- shop participants identified a possible increase in conflicts associated to the decrease in human presence in ranchlands. Although illegal hunting of carnivores appears to be the most common response to conflicts, ran- chers showed interest and motivation to explore mitigation measures. The comprehension of the socio-eco- nomic dynamics occurring in the SW of Buenos Aires is extremely urgent for conflict mitigation. Nevertheless, long term solutions will require the engagement of local communities and different government institutions. Keywords: predation, patagones, villarino, livestock, puma, pampas fox. 1GECM (Grupo de Ecología Comportamental de Mamíferos), Cátedra. Fisiología Animal, Depto. Biología, Bioquímica y Farmacia, Uni- versidad Nacional del Sur, San Juan 670, 8000 Bahía Blanca, Argentina. Correo electrónico: [email protected] 2CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina. 3INBIOSUR-UNS-CONICET (Instituto de Ciencias Biológicas y Biomédicas del Sur), Bahía Blanca, Argentina. Received August 4 2016 // Accepted March 7 2017 // Published online July 5 2017 Carnivores in the southwest of the province of Buenos Aires: ecology and conflicts with farmers August 2017, Argentina 5 INTRODUCTION Many times the losses due to predation call more atten- tion to the producer than inadequate sanitary, reproductive The order Carnivora includes 286 species (Wilson and or nutritional management and lead to an overestimation of Reeder, 2005), 28 of which are found in Argentina (Ojeda the importance of the conflict (Polisar et al., 2003). et al., 2012). They are mostly predators located at the top of the trophic pyramid (Redford and Eisenberg, 1992) and The southwest region accounts for 25% of the territory which feed mainly on vertebrates (Emmons, 1987). of the province of Buenos Aires and is characterized as a mixed production area, in which livestock has an important These species have a fundamental role in the ecosystems role. Fundamentally, the action of man in this region has where they live due to the top-down control they can exert been focused on the clearing and transformation of natural over the populations they prey (Ritchie and Johnson, 2009). forests (known as “montes”) into pastures and crops (Isla Most carnivores need large territories to survive and, the- et al., 2003). refore, extensive areas are necessary to guarantee the via- Beyond its limited natural productivity, associated to poor bility of their populations (Noss et al., 1996; Ray et al., 2005). and poorly developed soils and scarce rainfall, there is an The loss and fragmentation of habitats, and the perse- unsustainable management of livestock, which threatens the cution by men are three of the main threats to carnivores functionality of ecological processes, species diversity and (Loyola et al., 2008; Crooks et al., 2011). The aforemen- economic productivity (Distel, 2016 ). All these factors have tioned characteristics make these species very vulnerable led to a strong degradation of soils (Bouza et al., 2016). to disturbances of environments and fragmentation (Lyra- This work aims at summarizing the main results obtained Jorge et al., 2010; Crooks et al., 2011). In Argentina, the to date by the Mammalian Behavioral Ecology Group [Grupo modification of natural habitats is a common phenomenon, de Ecología Comportamental de Mamíferos] of the Univer- especially in the central region where most of the popu- sidad Nacional del Sur, in two fundamental aspects: (1) the lation is concentrated. This is due to the advance of the use of habitat by the four most abundant species of carnivo- agricultural-livestock frontier (Brown et al., 2006). res in this region (the skunk, Conepatus chinga; Geoffroy’s Real et al. (2003) concluded that human activities are the cat, Leopardus geoffroyi; the Pampas fox, Pseudalopex most influencing factor affecting the distribution of carnivo- gymnocercus; and the cougar, Puma concolor) describing res in Argentina. In association with these transformations, the factors that most influence this process; and (2) the cha- there is a reduction in the abundance of native prey and racterization of the level of the conflict between producers the introduction of domestic livestock that, in turn, generate and carnivorous, paying particular attention to the perception conflicts between carnivores and humans (Treves and Ka- and attitudes of producers against predators. ranth, 2003). Depredation by wild animals, such as carnivores, has MATERIALS AND METHODS always been an important problem for livestock, especia- lly in South America (Baker et al., 2008; Zarco-González Study area et al., 2012). Although there are other causes of conflict For this study we formulated the following predictions in (transmission of diseases, direct attacks on humans), the regards to the habitat use pattern: greatest problems with predators is that they feed of lives- tock, which can cause significant economic losses to rural 1. Cougars would avoid the most fragmented, with the producers (Woodroffe, 2000; Baker et al., 2008). greatest human presence areas, and would use the most preserved areas more. The most common response to this type of problem is the elimination of predators (Linnell et al., 1996; Inskip and 2. Given the great hunting pressure exerted over the Zimmermann, 2009). However, this type of solution usua- Pampas fox, a certain level of avoidance is expected lly fails to solve the problem in the long term, perpetuating in those areas with the greatest human presence. At an ecological imbalance that can exacerbate the conflict the same time, an association to relatively open envi- (Snow, 2008) and bring some species to the limits of ex- ronments is expected, in agreement with the results of tinction (Goodrich y Buskirk, 1995; Wallach et al., 2009). previous studies. Many factors can influence the decision of a predator to 3. Since Geoffroy’s cat is one of the least generalist spe- hunt livestock, including learned behavior, lack of native cies of the group, a significant response of Geoffroy’s prey, lack of adequate management practices, tolerance to cat to environmental gradients is expected. Also, a humans and often habitat characteristics (Rosas-Rosas et strong association of this species to areas with the hig- al., 2008) and all of them must be evaluated when planning hest proportion of monte is expected. effective management actions. In addition, when analyzing 4. A greater association of the Molina’s hog-nosed skunk to conflicts with fauna, social, ethical, and cultural aspects sites near the crops is expected, as they have been pro- must be considered, as they frequently affect social actors posed as favorable environments for this species. and may increase the perception of the magnitude of con- flicts with a given species (Dickman, 2010; Marchini y Mac- Based on these assumptions, this study was conducted donald, 2012). in private fields located in the districts of Villarino and Pa- CARUSO, N.1,2; LUENGOS VIDAL, E.M.1,3; LUCHERINI, M.1,2; GUERISOLI, M.1,2; MARTINEZ, S.1; CASANAVE, E.B.1,3 ARTICLES RIA / Vol. 43 / N.º 2 tagones,