Search

The lethal control of carnivores in order to protect livestock is a common practice worldwide, but its effectiveness has been poorly evaluated and is still unclear. Pumas (Puma concolor) are considered by ranchers one of the main sheep predators in Patagonia, and their hunting is ncouraged by the by the provincial estates through a state bounty system. This management measure does not include the examination and monitoring of the removed individuals. Our objective was to determine the age and sex structure of cougars hunted through the state bounty system in Chubut and Santa Cruz. We examined 411 skulls collected in both provinces. The age of each specimen was estimated by their tooth-wear pattern, established on the basis of skulls of known age. Sex was specified by hunters or obtained through a discriminant analysis based on four cranial measurements taken from specimens of known sex. The greatest proportion of individuals in both provinces corresponds to class I or sub -adults (between 16 months and two years of age) (43.6% in Chubut and 46.5% in Santa Cruz), followed by cubs (up to 16 months old) and the successive age-classes. The bias towards younger age classes could be related to their relative abundance in the population together with their vulnerability to harvest. The state bounty system does not provide real benefits to livestock ranchers. Effort and resources for the management of cougars should be used to develop alternative strategies that address the issues discussed here and that benefit both the productive sector and the conservation of the species. [ABSTRACT FROM AUTHOR]

High-altitude cushion peatlands contain important records for high-resolution palaeoenvironmental studies, due to their high carbon accumulation rates and sensitivity to climatic changes. In this study, we present the paleoenvironmental history for the last 2 500 years based on the study of APA01 core, located in the headwaters of the Cachi river basin in Ayacucho. Radiocarbon dating by an accelerator mass spectroscopy (AMS) and by an elemental PDZ Europa ANCA-GSL analyzer to estimate particulated organic carbon were determined. Our results reveal changes in the peatlands during the Late Holocene. The palaeo climate varied significantly during the last 2 500 years. During the Medieval Climatic Anomaly (ACM) from around 1040 DC (Before Christ - BC, in spanish paper) to 1300 DC, the drier climate caused a slowdown in peat accumulation due to a reduced water table inducing a reduced organic matter production with a negative peak of carbon concentration. At the end of the Small Ice Age (PEH), between 1600 DC and 1890 DC, carbon accumulation showed high variability. Subsequently, the peat environment is mainly characterized by a considerable increase of carbon accumulation rates due to high sedimentation rates that is possibly related to the retreat of glaciers in the Central Andes. The recent drastic increase in the sedimentation rate and the reduction of carbon concentrations are a warning of a possible future decline of these ecosystems. [ABSTRACT FROM AUTHOR]