Hoary Bat (lasiurus cinereus)


  • Weight: 5/8 - 1 oz. (19-28 g)
  • Body length: 4 7/8 - 5 5/8 in. (123-142 mm)
  • Wingspan: 13-16 in. (34-41 cm)
  • Forearm: 2 - 2 1/8 in. (52-54 mm)

The hoary bat is the largest bat in Maryland with a wingspan of up to 16 inches! It is a tree bat that has a fully furred tail membrane like the eastern red bat. The fur is distinctly banded with blackish, brown, or tan colors at the base and white “frosting” at the tips giving the bat a hoary appearance. The fur around the throat and forehead is yellow.

Hoary bats have a swift and direct flight which coupled with their size makes it somewhat easy to distinguish in flight.


  • Summer Roost: Like the eastern red bat, hoary bats are solitary. They typically roost 7-20 feet above the ground in coniferous tree, often near cleared areas.
  • Winter Roost: Typically, hoary bats in Maryland migrate south for the winter and will hibernate in coniferous trees.

Moths, true bugs, mosquitoes, other insects.

Hoary bats are listed as species of greatest conservation need in Maryland. In addition, they are ranked as vulnerable/apparently secure (S3S4).

Hoary Bat Call - Courtesy of Bat Call: Acoustic Call Library and Species Accounts

Hoary Bat Spectrograph

- Courtesy of Bat Call: Acoustic Call Library and Species Accounts
Echolocation Frequency: 21-32 kHz

Photo by: Dr. J. Scott Altenbach​

Return to Field Guide to Maryland Bats​