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The Argentinian Ministry of Environment has approved the translocation of 45 guanacos from Southern Patagonia to the Pampas region, a distance of 1500 km, as the initial phase toward future translocations into a National Park located in the Chaco region, another 1600 km further North. This decision raises concerns about the technical and ethical aspects of the translocation. Firstly, there is a lack of proper evaluation and scientific evidence to support the need, opportunity, and feasibility of this translocation. The guanaco population is currently over one million and is increasing, and genetic differences exist among local populations. The translocation could produce anthropogenic‐driven admixed populations, leading to genetic swamping and disrupting evolutionary processes. Second, there are ethical conflicts around managing wild species populations that prioritize private objectives and disregard local, publicly funded science. Rewilding projects require a deep understanding of interacting ecosystem processes, and of the socio‐economic context. This management decision violates guiding principles for rewilding and should have followed proper scientific evaluation and transparent local consultation. [ABSTRACT FROM AUTHOR]

We characterized the habitat use by maras (Dolichotis patagonum) on a microhabitat scale in the area surrounding the warren, assessing the conditioning effect of the warren over space use and exploitation of other resources. We evaluated the relationships between the probability and intensity of use, habitat configuration and distance to the warren, counting feces along transects departing from each warren. Our results showed that the location of breeding warrens was positively associated with the habitat use by maras on a microhabitat scale. The core area of the annual activity of maras was concentrated around the warren and there was no evidence of alternative areas of activity. According to the fitted models, maras used microhabitats with a high proportion of bare soil and close to infrastructure elements. The spatial autocorrelation components indicated that intensively used patches are small and disperse. The patterns of habitat use observed in this study suggest that maras use multipurpose areas including the breeding site and resources needed throughout the year. These patterns suggest that warrens are good all year-round indicators of mara habitat use and spatial ecology. [ABSTRACT FROM AUTHOR]

There is an urgent need to characterize the relationships between endangered species and their habitats in response to the accelerating pace of habitat transformation by humans. Mara (Dolichotis patagonum) is a large rodent endemic to the Argentine semi-deserts. It has been classified as “Near Threatened” by IUCN mainly as the result of habitat loss. There is contradictory evidence about the impact of human activities on mara and further information is needed to develop effective conservation strategies. We describe the main environmental factors, both natural and human, that are associated with warren presence as an indicator of the habitat selected by maras at the landscape scale. Habitat selected by maras was characterized by a high proportion of bare soil, low β diversity, open herbaceous steppe, and proximity to fences. The relationship of warren presence to the proportion of shrubby steppe in the broader landscape was variable across environments being positive in grasslands, and negative in shrubbier habitats. This supports the hypothesis that mara's preference for open areas depends on the level of shrubs in the surrounding habitat. As a result, conservation efforts will need to be tailored to the amount and structure of vegetation in any given area. [ABSTRACT FROM AUTHOR]

In Patagonia, the functional relationships between pumas and their native prey species have been modified as a result of the introduction of exotics. We studied the feeding habits of Puma concolor in northeastern Chubut province during 3 years and found that (1) the native guanaco, Lama guanicoe, was the most important prey in the diet of pumas; (2) pumas expanded their trophic niche by incorporating smaller prey species to their diets after a substantial reduction in the abundance of the introduced sheep; and (3) puma predation was the main cause of guanaco mortality. [ABSTRACT FROM AUTHOR]

Simple Summary: Determining the impacts of human activities on natural populations is important for biodiversity conservation. In this paper, we study the past and more recent effects of urbanization and livestock activity on the genetic diversity and population structure of endemic guanaco populations of the arid Monte and Patagonian Steppe of central Argentina. Our results reveal that urbanization, the installation of fences, and the competition from sheep grazing coincided with the isolation of several guanaco populations, especially in areas with the highest intensity of livestock activity. However, our genetic analyses suggest that a more recent increase in connectivity among groups is occurring. Our results highlight the importance of implementing conservation management plans for natural populations in arid and human-intervened environments. Extensive livestock production and urbanization entail modifications of natural landscapes, including installation of fences, development of agriculture, urbanization of natural areas, and construction of roads and infrastructure that, together, impact native fauna. Here, we evaluate the diversity and genetic structure of endemic guanacos (Lama guanicoe) of the Monte and Patagonian Steppe of central Argentina, which have been reduced and displaced by sheep ranching and other impacts of human activities. Analyses of genetic variation of microsatellite loci and d-loop revealed high levels of genetic variation and latitudinal segregation of mitochondrial haplotypes. There were indications of at least two historical populations in the Monte and the Patagonian Steppe based on shared haplotypes and shared demographic history among localities. Currently, guanacos are structured into three groups that were probably reconnected relatively recently, possibly facilitated by a reduction of sheep and livestock in recent decades and a recovery of the guanaco populations. These results provide evidence of the genetic effects of livestock activity and urbanization on wild herbivore populations, which were possibly exacerbated by an arid environment with limited productive areas. The results highlight the importance of enacting conservation management plans to ensure the persistence of ancestral and ecologically functional populations of guanacos. [ABSTRACT FROM AUTHOR]

Mammals are key components of biodiversity mediating ecosystem functions, mainly because of the diversity of forms and functions of this group. Understanding and making explicit the role of mammals underpinning Nature's Contributions to People (NCP) or directly contributing to human well-being would help to influence policy formulation towards sustainable development and nature conservation. Through a workshop held at the XXXII Jornadas Argentinas de Mastozoología and subsequent collaborative work, we compiled information related to Mammal's Contributions to People in Argentina (MCP-Arg) based on participants' interpretation of the available literature and their field experience. Argentinian mammals contribute to 12 of the 18 defined NCPs. We derived numerous MCP-Arg from studies that focused mainly on ecological processes and conservation, revealing an information gap in MCP-Arg description, quantification, and mapping. All taxa contribute similarly to the overall contributions, highlighting the importance of preserving mammal diversity. Conservation should also be framed at the local community rather than regional scales, aiming to preserve ecological functioning and contributions to human well-being, especially within regulation contributions. Our results show destructive feedback between threats and habitat-related contributions, with habitat degradation being the greatest threat to mammalian contributions and habitat maintenance the most threatened one. Our research indicates that a substantial amount of knowledge about MCP-Arg is available through narratives and interpretations. Considering the NCP approach to mammalian research, we can make significant contributions to both mammal conservation and human well-being. [ABSTRACT FROM AUTHOR]

Ungulates living in predator-free reserves offer the opportunity to study the influence of food limitation on population dynamics without the potentially confounding effects of top-down regulation or livestock competition. We assessed the influence of relative forage availability and population density on guanaco recruitment in two predator-free reserves in eastern Patagonia, with contrasting scenarios of population density. We also explored the relative contribution of the observed recruitment to population growth using a deterministic linear model to test the assumption that the studied populations were closed units. The observed densities increased twice as fast as our theoretical populations, indicating that marked immigration has taken place during the recovery phase experienced by both populations, thus we rejected the closed-population assumption. Regarding the factors driving variation in recruitment, in the low- to medium-density setting, we found a positive linear relationship between recruitment and surrogates of annual primary production, whereas no density dependence was detected. In contrast, in the high-density scenario, both annual primary production and population density showed marked effects, indicating a positive relationship between recruitment and per capita food availability above a food-limitation threshold. Our results support the idea that environmental carrying capacity fluctuates in response to climatic variation, and that these fluctuations have relevant consequences for herbivore dynamics, such as amplifying density dependence in drier years. We conclude that including the coupling between environmental variability in resources and density dependence is crucial to model ungulate population dynamics; to overlook temporal changes in carrying capacity may even mask density dependence as well as other important processes. [ABSTRACT FROM AUTHOR]