Habitat Suitability Index Modelling for the Mara (Dolichotis patagonum) in the central Argentinean Dry Chaco.

Habitat Suitability Index (HSI) models are practical and cost-effective tools for assessing habitat quality based on existing species ecological knowledge. Here, we developed a spatially explicit HSI model for Dolichotis patagonum (Zimmermann, 1780), a nationally Vulnerable rodent, to assess habitat quality and distribution in the central Argentinean Dry Chaco, a region undergoing significant land-use changes. We integrated variables representing habitat requirements (land cover and distance to water) and human impacts (distance to settlements and roads, and fire frequency), selected from the literature and spatialized using geospatial data sources. We estimated partial suitability indices for each variable and combined them mathematically to obtain the final HSI. Suitability values ranged from 0.13 to 0.74 and were reclassified into high (11.0% of the area), moderate (81.6%), and low suitability (7.4%), with no optimal habitats (HSI = 1) detected. High-suitability areas were mainly associated with open shrubland and grassland-shrubland cover, whereas low-suitability areas coincided with cropland and recurrent fires. Suitability patterns varied among jurisdictions, reflecting local land-use influences on habitat quality. Model validation showed that field records fell within areas of moderate to high suitability, supporting the model's ability to represent patterns of suitable habitat and thereby its potential applicability for mara conservation planning.