Food habits of the hoary bat (Lasiurus cinereus) during spring migration through New Mexico
Product Type:Journal Article
Author(s):Valdez, E.W. and P.M. Cryan
Suggested Citation:Valdez, E.W. and P.M. Cryan. 2009. Food habits of the hoary bat (Lasiurus cinereus) during spring migration through New Mexico. Southwestern Naturalist. 54(2): 195-200.
Hoary bats (Lasiurus cinereus) exhibit continental patterns of migration that are unique to bats, but details about their behaviors during migration are lacking. We captured 177 hoary bats in spring and early summer 2002 as individuals migrated through the Sandia Mountains of north-central New Mexico. Our results support earlier observations of asynchronous timing of migration between sexes of L. cinereus during spring, with females preceding males by ca. 1 month. We provide the first evidence that hoary bats may travel in dispersed groups, fly below the tree canopy along streams, and feed while migrating during the spring. Analysis of guano revealed that the diet of L. cinereus consisted mostly of moth, with more than one-half of samples identified as Noctuidae and Geometriae. We observed a late-spring decline in consumption of moths that might be related to seasonal changes in abundance of prey, differential selection of prey by bats, or sampling bias. We suspect that spring migration of L. cinereus through New Mexico temporally coincides with the seasonal abundance of moths.