ABSTRACT.—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.
Additional publication details
Landscape movements by two species of migratory nectar-feeding bats (Leptonycteris) in a northern area of seasonal sympatry