A small bat that's been devastated by white-nose syndrome. Was once one of the most abundant US bats.

Native status: Native; federally endangered

§ Quick facts

SizeBody 6–10 cm; wingspan 22–27 cm
Weight5–14 g
LifespanWild 6–7 years (some 30+)
OrderChiroptera
FamilyVespertilionidae

§ Encyclopedia

The little brown bat or little brown myotis is an endangered species of mouse-eared microbat found in North America. It has a small body size and glossy brown fur. It is similar in appearance to several other mouse-eared bats, including the Indiana bat, northern long-eared bat, and Arizona myotis, to which it is closely related. Despite its name, the little brown bat is not closely related to the big brown bat, which belongs to a different genus.

Source: Wikipedia — Little brown bat Licensed under CC BY-SA 4.0

§ Identification

Field marks. Small chocolate-brown bat with glossy fur and pale belly.

Similar species. Other Myotis species. Indiana Bat.

Voice. Ultrasonic echolocation.

§ Diet & behavior

Diet. Flying insects.

Behavior. Once one of most abundant US mammals. White-nose syndrome has caused 90%+ population decline. Federally endangered.

§ Range

Across North America

§ Habitat

Diverse: caves, mines, buildings

§ Threats

White-nose syndrome devastating populations, climate change.

§ Conservation status

According to the IUCN Red List, the little brown myotis is currently classified as Endangered.

§ What helps

Support white-nose research. Don't disturb caves.

Support our work More ways to help

§ Further reading

§ Sources cited

  • USFWS Little Brown Bat
  • USGS National Wildlife Health Center
  • IUCN Red List 2018