Great Plains Natural Science Society


The Prairie Naturalist

Date of this Version


Document Type



THE PRAIRIE NATURALIST, Volume 37, No. 1, March 2005, pp 41-42.


Published by the Great Plains Natural Science Society. Used by permission.


Although common in deciduous forest throughout the Midwest and east-central states, the eastern red bat (Lasiurus borealis) is rare in Colorado (Armstrong et al. 1994, Fitzgerald et al. 1994). However, this species has the potential to extend its range because belts of eastern deciduous forest habitat have expanded across western prairies and reached the Front Range of Colorado over the last 100 years (Knopf 1986). The eastern red bat ranges from Canada southward across the United States to northeastern New Mexico with most records occurring east of the Continental Divide (Hall 1981, Shump and Shump 1982, Cryan 2003). The historical range of the eastern red bat in Colorado extends along the riparian forest habitat of the South Platte and Arkansas rivers of eastern Colorado as far west as Boulder and Pueblo counties, respectively. Previous records of this species in Colorado are either individual animals caught incidentally or those submitted by the public to the Colorado Division of Public Health and Environment that lacked accurate location information (Armstrong et al. 1994). Everette et al. (2001) tentatively identified the presence of red bats on the outskirts of Denver, Colorado as recently as 2 and 7 July 1997, based on four echolocation calls recorded with Anabat detectors. Despite extensive mist netting, no red bats were captured. No new records have been reported for this species in Colorado since that time.