Protected area effectiveness for conserving rodent diversity in the Sierra Madre Oriental under climate change

Abstract

Global biodiversity loss is accelerating, driven by multiple factors, including climate change. Protected areas are a cornerstone of conservation strategies; however, their effectiveness is often constrained by limited climate-resilience planning and taxonomic biases that often overlook ecologically important but non-charismatic groups, such as rodents. We analyzed rodent species richness in the Sierra Madre Oriental, Mexico, evaluating conservation effectiveness within protected areas (which cover 29% of the region) under climate change scenarios. Potential species richness for 85 rodent species was estimated using ensemble species distribution models under current conditions and future climate scenarios (RCP4.5 and RCP8.5) for projections to 2030, 2050, and 2070. Temporal trends in potential species richness were evaluated by Mann-Kendall trend test. Additional comparisons included bioclimatic corridors and functional groups (generalists and specialists). Results suggest that protected areas currently encompass all modeled rodent species in the Sierra Madre Oriental (excluding Dipodomys spectabilis, Geomys personatus and Sigmodon mascotensis), however, they do not fully overlap with areas of highest species richness, which are located in the southern Sierra Madre Oriental. Also, an overall decline in high-richness areas by 2070, particularly under the RCP8.5 scenario, where species losses in some protected areas could reach up to 35 species. Although generalist species exhibit relative stability, an overall decreasing trend in species richness is expected in most protected areas, with significant compositional changes projected for specialist species. Notably, bioclimatic corridors were found to host species currently absent from protected areas and to support the same proportion of species classified as at risk. Implementing climate-smart strategies, such as establishing and reinforcing bioclimatic corridors to improve connectivity, is recommended to mitigate biodiversity loss and enhance conservation resilience in the Sierra Madre Oriental.