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Human activity has caused the decrease of about 20 % of the planet's vertebrate diversity and 25 % in their abundance. Many large and medium-sized herbivore mammals have gone extinct locally, unleashing a cascade of ecosystem changes. The spotted paca (Cuniculus paca) is impacted by hunting and anthropogenic habitat fragmentation and loss. To protect spotted pacas, it is essential to estimate anthropogenic effects on their geographic distribution. Through the use of primary biodiversity data, bioclimatic data, land-cover data, and a human footprint index, we modeled the distribution of C. paca. From 105 candidate models, only one model met our selection criteria. The variables with the highest contribution were the human footprint and annual precipitation. According to the model's performance curves, the spotted paca has low to medium tolerance of anthropogenic pressure. Cuniculus paca tolerates low to medium anthropogenic disturbance, which we hypothesize is related to reduced predator pressure in habitats modified by humans. Accounting for the costs and benefits of anthropogenic disturbance is essential to paca conservation. La actividad humana ha disminuido alrededor del 20 % de la diversidad biológica del planeta, así como del 25 % de la abundancia de los vertebrados. Esto ha llevado a mamíferos herbívoros grandes y medianos a extinguirse localmente, desatando una cascada de cambios en los ecosistemas. El tepezcuintle (Cuniculus paca) sufre una importante presión antropogénica debido a la cacería y pérdida de hábitat, por lo que es importante estimar sus efectos sobre su distribución para su conservación y manejo. Modelamos la distribución del tepezcuintle mediante el uso de datos primarios de biodiversidad de acceso libre, variables bioclimáticas, cobertura arbórea y un índice de huella humana que refleja la presión antropogénica sobre los ecosistemas. De 105 modelos candidatos, únicamente uno cumplió con los criterios de selección. Las variables con la mayor contribución fueron la huella humana y la precipitación anual. A partir de las curvas de respuesta del modelo, se observó en la especie una tolerancia a la antropización de baja a media. Estos resultados podrían deberse a que en ambientes antropizados los depredadores del tepezcuintle han disminuido sus tamaños poblacionales. Entender los costos y beneficios de la perturbación antropogénica es esencial para la conservación del tepezcuintle. [ABSTRACT FROM AUTHOR]

Recent studies have used occupancy models (OM) and ecological niche models (ENM) to provide a better understanding of species' distributions at different scales. One of the main ideas underlying the theoretical foundations of both OM and ENM is that they are positively related to abundance: higher occupancy implies higher density and more suitable areas are likely to have more abundant populations. Here, we analyze the relationship between habitat use measured in terms of occupancy probabilities from OM and environmental suitability derived from ENM in three different Neotropical mammal species: Leopardus wiedii , Cuniculus paca , and Dasypus novemcinctus. For ENM, we used climatic and vegetation cover variables and implemented a model calibration and selection protocol to select the most competitive models. For OM, we used a single-species, single-season model with site covariates for camera-trap data from six different sites throughout the Neotropical realm. Covariates included vegetation percentage, normalized difference vegetation index, normalized difference water index, and elevation. For each site, we fit OM using all possible combinations of variables and selected the most competitive (ΔAICc < 2) to build an average OM. We explored relationships between estimated suitability and occupancy values using Spearman correlation analysis. Relationships between ENM and OM tended to be positive for the three Neotropical mammals, but the strength varied among sites, which could be explained by local factors such as site characteristics and conservation status of areas. We conjecture that ENM are suitable to understand spatial patterns at coarser geographic scales because the concept of the niche is about the species as a whole, whereas OM are more relevant to explain the distribution locally, likely reflecting transient dynamics of populations resulting from many local factors such as community composition and biotic processes. [ABSTRACT FROM AUTHOR]