Roost use by bats (Chiroptera: Phyllostomidae) in the Natural Area Los Estoraques, Norte de Santander, Colombia. Roost ecology is important for bats evolution and biology. We described roost use in a dry forest of north eastern Colombia. Relations between roost environmental variables (temperature, relative humidity, wind speed, light, perch height, maximum height of roost and altitude) and relative abundance of Artibeus jamaicensis, Carollia brevicauda and Anoura geoffroyi during dry and rainy seasons were determined. Differences between environmental variables of roosts using variance analysis and Kruskal-Wallis tests were determined. The relation between environmental variables and abundance was assessed with a canonical correspondence analysis (CCA). Eight natural and three artificial roosts were found. Regarding environmental variables, light, maximum height of roost and perch height showed significant differences among roosts, while wind speed, relative humidity and temperature presented no variation. Associations between A. jamaicensis and relative humidity, wind speed, light, perch height and maximum height of roost were found through CCA. For C. brevicauda and A. geoffroyi, an association with temperature and altitude, respectively, was found. Abundance of A. jamaicensis varied in