Gallery forests and open savannas are key habitats for terrestrial mammals in the Colombian Llanos

Habitat conditions are fundamental to provide essential requirements for mammal species to ensure their viability in natural communities. The Colombian Llanos are home to a high mammal biodiversity, but few studies in this region have addressed key aspects of their natural history, such as habitat use and preference. In this study, we evaluated medium and large-size mammal use of gallery forests and open savannas in two locations within the Colombian Llanos, analyzing species’ habitat preferences with the hypothesis that mammal species would use and prefer gallery forests over open savannas. We installed 60 camera traps in two sites for 35 days (2100 camera traps / days), covering habitats of both gallery forests and open savannas. Detected species’ relative abundances were subjected to Chi-square analysis and Bonferroni 95 % confidence intervals to assess their habitat use and preferences. All recorded mammal species used the gallery forest and ≈ 50 % of these species exclusively used it. Forest preference was high among mammals, but some species found complementary resources in open savannas. Only capybaras revealed a significant preference for the open savanna. We highlight the importance of conserving gallery forests and open savannas in the Colombian Llanos to improve habitat conditions that guarantee mammal survival. Landowners should be encouraged to deploy conservation initiatives to ensure the long-term protection of natural areas required by mammal species.