RESUMO

The Pampas fox (Lycalopex gymnocercus) has suffered from hunting and human persecution for decades, both for fur trade or due to conflicts with livestock. However, studies assessing the effects of hunting pressure on this canid population ecology are lacking. In this work, we assessed the influence of several hunting-related variables on the daily activity patterns and habitat use of the Pampas fox. In private farms of central Argentina, we performed two camera-trapping surveys: one during the non-hunting season and other during the hunting season, distinguishing between sites with or without access by hunters. The habitat use of Pampas foxes did not vary between seasons, but their detectability was lower during the hunting season in habitats that allow humans to see foxes easily (i.e., habitats with high visibility). Pampas foxes selected dusk and night-time, increasing their activity at dusk hours on sites with hunting and showed differences in activity patterns related with the level of visibility of the habitat and to season. Hunting pressure may interact with anthropogenic habitat modifications and create ecological traps for the Pampas fox in agroecosystems.

Assuntos

Ecossistema , Raposas , Animais , Argentina , Humanos

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0206513.].

RESUMO

Biological invasions are one of the main components of human-caused global change and their negative impact on invaded ecosystems have long been recognized. Invasive mammals, in particular, can threaten native biodiversity and cause economic impacts in the region where they are introduced, often through a wide range of conflicts with humans. Although the wild boar, Sus scrofa, is considered by the IUCN as one of the 100 invasive species most damaging to biodiversity in the world, in Argentina there have only been a few studies focused on its ecology with most of them conducted in protected areas. In this study, we evaluated the effect of several factors related with human disturbance, landscape composition, degree of fragmentation and the presence of a potential competitor and a predator on the habitat use of wild boar using data from camera traps and site-occupancy modeling. Additionally, we described the daily activity pattern of the species and we studied the level of overlap with both a potential competitor and a predator. The sampling effort totaled 7,054 camera trap days. Farm density, proportion of shrubland and proportion of grassland with bushes were the detection variables included in the most supported model whereas proportion of grassland and capture rate of the Pampas fox Lycalopex gymnocercus were the occupancy variables included in the most supported model. However, the proportion of grassland was the only variable that showed statistically significant support in the averaged model, indicating that habitat use of wild boar in this area was significantly negatively affected by the level of grass cover. Wild boars were mostly nocturnal, with more activity between 21:00 and 3:00 and a peak around midnight. Wild boars showed a high level of overlap with the activity pattern of the Pampas fox and a low overlap with the activity pattern of the puma Puma concolor. Despite wild boar being introduced in Argentina a few decades ago, this study is the first landscape-scale research carried out in an agricultural landscape in Argentina and the first one based on camera-trapping data. Our study contributes valuable information that could be used to design strategies to reduce wild boar population or to minimize the damage caused by this invasive species in Argentina.

RESUMO

Livestock predation is one of the major causes of conflicts between humans and pumas (Puma concolor). Using data from interviews with ranchers and kill-site inspections, we characterized puma-livestock conflicts in Villarino and Patagones counties of central Argentinean rangelands. Depredation was considered the major cause of livestock losses, and puma attacks were reported in 46.6% and 35.4% of ranches in Villarino and Patagones, respectively. The majority of ranches underwent losses smaller than 1000 USD. The proportion of livestock lost to predation (0.1-10.4%) and financial losses (5.3-1560.4 USD) per ranch/year varied across ranches, and small sheep ranches in Villarino were affected the most. Depredation was recorded only at night and preferentially in grassland with shrubs and cropland habitats. Although nocturnal enclosures appeared to decrease sheep losses, puma hunting was considered the most effective form of reducing depredation and was implemented by most ranchers. Mortality rates were 3.7 and 1.1-1.56 individuals/year × 100 km2 for sheep and pumas, respectively. Nocturnal fencing, shepherding and spatial separation from predators may efficiently reduce sheep losses. However, the poor association between the intensity of puma persecution and puma-related livestock losses suggests that conflict mitigation in central Argentina is not only about reducing damage but also about increasing tolerance.