摘要：Animals often migrate to exploit seasonally ephemeral food. Three species of nectar-feeding phyllostomid bats migrate north from Mexico into deserts of the United States each spring and summer to feed on blooms of columnar cactus and century plants (Agave spp.). However, the habitat needs of these important desert pollinators are poorly understood. We followed the nighttime movements of 2 species of long-nosed bats (Leptonycteris yerbabuenae and L. nivalis) in an area of late-summer sympatry at the northern edges of their migratory ranges. We radio-tracked bats in extreme southwestern New Mexico during 22 nights over 2 summers and acquired location estimates for 31 individuals. Both species cohabitated 2 major day roosts that were 30 km apart and in different mountain ranges, and individual bats sometimes moved between the roosts. Sampling was opportunistic and limited, but there were no obvious qualitative differences in observed patterns of movement between species or years, or among sex, age, and reproductive groups. Both species were observed foraging most often in the mountain range that had a relatively higher observed density of presumed food plants (Agave palmeri); when roosting in an adjacent mountain range, bats sometimes commuted >20 km one way to forage. Contrary to evidence indicating these species partition resources farther south in Mexico, our findings suggest that L. yerbabuenae and L. nivalis seasonally share common roost and food resources during late summer in this northern area of sympatry.A menudo, los animales migran en búsqueda de alimentos, propios de cada estación. Tres especies de murciélagos filostómidos que se alimentan de néctar migran cada primavera y verano, desde el norte de México hacia los desiertos de Estados Unidos para alimentarse de las floraciones de cactáceas columnares y de agaves americanos (Agave spp.). Sin embargo, las necesidades en relación al hábitat de estos importantes polinizadores del desierto son poco conocidas. Estudiamos los movimientos nocturnos de dos especies de murciélagos magueyeros (Leptonycteris yerbabuenae y L. nivalis) en una área de simpatría a finales del verano, en los límites norteños de sus rangos migratorios. Rastreamos murciélagos con radiotransmisores al extremo suroeste de Nuevo México durante 22 noches en dos veranos y estimamos los puntos de ubicación de 31 ejemplares. Ambas especies coexistieron en dos refugios principales separados por 30 kilómetros de distancia y en distintas cadenas montañosas. Sin embargo, en ocasiones, los murciélagos se trasladaron por sí solos de un refugio a otro. El muestreo fue oportunista y limitado, pero
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