• Moreno-Valdez, Arnulfo

In this study we analyze the population dynamics of the migratory and nectarivorous Leptonycteris nivalis (Mexican long-nosed bat) in relation to food abundance and environmental factors (temperature and humidity). A 2-year study was conducted in the Mexican state of Nuevo Leon. Bat densities and the number of blooming Agave were estimated by month at El Infierno cave and surrounding areas. Temperature and humidity were recorded at 4.5-h intervals inside and outside the bat roost. Bat density was estimated visually, and the number of blooming Agave was counted in 70 fixed plots along 3 road transects within a 50-km radius of the cave. Examination of data indicates that abundance of L. nivalis at El Infierno cave is correlated with the frequency of blooming Agave and ambient temperature. However, cave temperature, humidity, and external humidity were not correlated with bat numbers. These findings suggest that conservation of this federally protected bat will require maintenance of relatively large areas of wild Agave.