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We studied the density of a Geoffroy's cat Leopardus geoffroyi population in a semiarid scrubland of Argentina, by comparing density estimates obtained during camera-trapping surveys in a national park and in nearby cattle ranches in 2006 and 2007-2008. Overall, we obtained 247 pictures of Geoffroy's cats. The density (mean AE SE) of the species at the park ranged from 1.2 AE 0.3 to 2.9 AE 1.4 individuals km À2 , depending on the buffer applied, whereas density estimates at ranches were on average 32% lower. Only 11% of the Geoffroy's cats identified in 2006 could still be detected in the area 2 years later, indicating that there was a high turnover of individuals in this population. The sex ratio (M:F) estimated during both surveys at the park was 1:1.4, whereas at the ranches it was 1:0.8. The capture success of sympatric pampas cats Leopardus colocolo and jaguarundis Puma yagouaroundi was o0.3 records per 100 trap-days, and no evidence of these species was found in the ranches. Geoffroy's cats seem to be tolerant to some degree of habitat alteration produced by livestock management, and the numerical response of this species in ranches could be largely the result of human persecution and the effects of livestock management on the habitat structure and prey base.

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We present quantitative data on the impact of different causes of mortality in a Geoffroy's cat (Leopardus geoffroyi) population inhabiting a protected area and adjacent cattle ranches in central Argentina. Between December 2000 and January 2009, we used three methods to collect data on causes of mortality in both the park and the ranches: (1) information obtained from 35 radiocollared Geoffroy's cats monitored from 1 to 19 months;(2) a systematic survey of the areas to find non-collared dead animals; and (3) interviews of qualified informants. Deaths of radio-collared individuals in the park were due to predation by puma (Puma concolor) or starvation, whereas deaths in the ranches were attributed to starvation and predation by domestic dogs. The death of eight emigrant cats was attributed mainly to poaching. Cause of death of 39 non-collared Geoffroy's cats was determined; deaths in the ranches were mainly due to predation by domestic dogs and poaching, whereas deaths in the park were attributed to predation by puma, poaching, and vehicle collision.Grouping all sources of information, human-related mortality accounted for most (62%) of Geoffroy's cat deaths recorded during this study, with poaching and predation by dogs being the main causes of mortality. This study in Geoffroy's cats is the first long-term survey of causes of mortality for a population of a small felid species in South America.

Wild ungulates, and particularly deer, can cause severe damage to commercial plantations, resulting in reduced tolerance of their presence by forestry producers. The marsh deer Blastocerus dichotomus, categorized as Vulnerable on the IUCN Red List, is declining throughout South America. A population of c. 500 individuals survive within a matrix of commercial plantations in the lower delta of the Paraná River, the southernmost stronghold for the species. Local forestry producers usually report that damage to plantations is attributable to marsh deer, thus justifying persecution of the species. Seventy-six forestry producers (representing c. 33% of the total plantation area of the lower delta) were interviewed using a semi-structured questionnaire to assess perceived levels of tree damage, associated economic losses, and attitudes towards the deer. Simultaneously, plantation stands were surveyed to quantify the actual tree damage caused by this ungulate. Seventy-six percent of producers reported damage to trees by deer (i.e. browsing, fraying caused by antler rubbing) but most of them perceived low levels of damage per property (median < 0.2%), with negligible economic effects. However, 5% of producers (all of them with ≤ 2 km2 in production, usually family enterprises) perceived high levels of damage and economic losses, and supported deer hunting as a management option. Field surveys indicated that damage caused by deer could be more severe than perceived by producers, although spatially confined within the landscape. Monitoring of damage perception by forestry producers, and compensation schemes to assist small producers are necessary for adequate management of this threatened marsh deer population.