Eastern Red Bat

(Lasiurus borealis)

Eastern Red Bat
Eastern Red Bat by John MacGregor

Description:  One of Kentucky’s larger bats, this species can reach up to 5 inches in length with a wingspan of approximately 13 inches. Both sexes are predominantly orangish to rusty in color, with males tending to be more brightly colored than the females. The fur on both is frosted with white tips, especially on the back and chest. In contrast, the wing membranes are largely blackish, making for a beautiful pattern to the spread wing. The ears are relatively short with a blunt tragus. Lasiurus actually means “hairy tail” and unlike most other Kentucky bats, the red bat’s tail membrane is heavily furred.

Range:  The species is widespread across much of North America from southern Canada, south through Central America to northern South America, absent only from the Rocky Mountains and southern Florida. 

Distribution in Kentucky:  See Map 

Kentucky Occurrence Summary:  The eastern red bat is common across Kentucky. It is most frequently encountered in summer, although substantial numbers likely pass through during migration and some overwinter in the state.

Habitat and Life History: This solitary tree bat inhabits forests, roosting primarily beneath clusters of leaves during spring, summer and fall. In this position, they mimic a dead leaf by hanging by one foot, reducing predation. Many red bats migrate southward in fall, moving far enough to avoid severe winter temperatures. Some have been observed in Kentucky overwintering in leaf litter. They are able to withstand freezing temperatures by decreasing their metabolism and wrapping themselves with their heavily furred tail membrane. Others may roost in hollow trees and fallen logs as well. Being out on the landscape like that makes them more in tune with changes in the ambient temperature. Warm winter weather often results in the appearance of a few foraging individuals. Red bats are rarely if ever observed in caves, although they may swarm with other bats at cave entrances in fall. These bats typically roost solitarily, rarely if ever forming small colonies. They forage along forest edge, streams, and often in residential areas around streetlights. They feed on a wide variety of insects including moths, flies, true bugs, beetles, cicadas, and even ground-dwelling crickets that are snapped up from the forest floor. Females give birth to one to four pups during late May and early June.

Eastern red bat hanging from tree foliage 
Eastern red bat hanging from tree foliage
Photo by John MacGregor
 
Eastern red bat captured in mist net  
Eastern red bat captured in mist
Photo by Traci Hemberger

Eastern red bat wing contrast Eastern red bat wing contrast
Photo by John MacGregor
 
Eastern red bat female with pups Eastern red bat female with pups
Photo by John MacGregor
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