Little brown bat
Myotis lucifugus (Le Conte, 1831)
The little brown bat (Myotis lucifugus) is a species in the family Vespertilionidae, order Chiroptera. Recorded adults weigh 7.15 g to 7.65 g and live up to 29 years. Its IUCN Red List status is Endangered.
Quick facts about the little brown bat
- Weight
- 7.15 g – 7.65 gsrc for Weight
- Length
- Not recorded
- Wingspan
- 23.3 cmsrc for Wingspan
- Lifespan
- 29 yearssrc for Lifespan
- Diet
- Invertivoresrc for Diet
- Longest recorded lifespan
- 34 years
- Main food
- Not recorded
- Habitat
- Not recorded
- Gestation
- 50 days – 60 dayssrc for Gestation
- Young per litter or clutch
- 1src for Young per litter or clutch
- Age at maturity
- 6.9 months – 8.06 monthssrc for Age at maturity
- Litters or clutches a year
- 1src for Litters or clutches a year
- Active
- At night (nocturnal)src for Active
- Lifestyle
- Aerialsrc for Lifestyle
- Conservation status
- Endangered (IUCN)src for Conservation status
- Countries on record
- Not recorded
How big is the little brown bat?
Where does the little brown bat live?
Not recorded
What is the little brown bat?
The little brown bat or little brown myotis (Myotis lucifugus) 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.
Its mating system is polygynandrous, or promiscuous, and females give birth to one offspring annually. The offspring, called pups, are quickly weaned and reach adult size in some dimensions by three weeks old. The little brown bat has a lifespan of 34-35 years. It is nocturnal, foraging for its insect prey at night and roosting in hollow trees or buildings during the day, among less common roost types. It navigates and locates prey with echolocation.
It has few natural predators, but may be killed by raptors such as owls, as well as terrestrial predators such as raccoons. Other sources of mortality include diseases such as rabies and white-nose syndrome. White-nose syndrome has been a significant cause of mortality since 2006, killing over one million little brown bats by 2011. In the Northeastern United States, population loss has been extreme, with surveyed hibernacula (caves used for hibernation) averaging a population loss of 90%.
Humans frequently encounter the little brown bat due to its habit of roosting in buildings. Colonies in buildings are often considered pests because of the production of waste or the concern of rabies transmission. Little brown bats rarely test positive for rabies, however. Some people attempt to attract little brown bats to their property, but not their houses, by installing bat houses.
From the Wikipedia article “Little brown bat” (en.wikipedia.org/w/index.php?title=Little_brown_bat&oldid=1383767566), by Wikipedia contributors, licensed under CC BY-SA 4.0 (creativecommons.org/licenses/by-sa/4.0). This block is kept separate from our own text.
Is the little brown bat endangered?
The little brown bat is listed as Endangered on the IUCN Red List: it faces a very high risk of extinction in the wild.
- LCLeast Concern
- NTNear Threatened
- VUVulnerable
- ENEndangered
- CRCritically Endangered
- EWExtinct in the Wild
- EXExtinct
Category via Wikidata (CC0). Find the full assessment on the IUCN Red List. See all Endangered species. What the categories mean.
How is the little brown bat classified?
- kingdomAnimalia
- phylumChordata
- classMammalia
- orderChiroptera
- familyVespertilionidae
- genusMyotis
- SpeciesMyotis lucifugus (Le Conte, 1831)
Other names and names in other languages (23)
- Little brown myotisEnglish
- Little brown myotisEnglish
- Little brown myotisEnglish
- Ratpenat bru americàCatalan
- netopýr hnědavýCzech
- Kleine Braune FledermausGerman
- Μικρή ΚαστανομυωτίδαGreek
- Miotis norteamericanoSpanish
- pikkuruskosiippaFinnish
- Murin brunFrench
- petite chauve-souris bruneFrench
- vespertilion brunFrench
- LjósfælaIcelandic
- Vespertilio brunoItalian
- Pipistrello perforatoreItalian
- トビイロホオヒゲコウモリJapanese
- Liten BrunflaggermusNorwegian Bokmål
- Kleine Bruine VleermuisDutch
- BapakwaanaajiiOjibwa
- Nocek amerykańskiPolish
- Малая бурая ночницаRussian
- Liten brun fladdermusSwedish
- ค้างคาวหูหนูสีน้ำตาลเล็กThai
Catalogue of LifeWikipediaiNaturalistTAXREFWikidataIUCN Red List
Relatives of the little brown bat
Other species in the same genus Myotis.
Natterer's bat
Myotis nattereri
Whiskered bat
Myotis mystacinus
Daubenton's bat
Myotis daubentonii
Greater mouse-eared bat
Myotis myotis
Brandt's bat
Myotis brandtii
Geoffroy's bat
Myotis emarginatus
CompareLittle brown bat vs Natterer's batLittle brown bat vs Whiskered batLittle brown bat vs Daubenton's batLittle brown bat vs Greater mouse-eared bat
Common questions
Answered only where our data holds the answer.
How big is the little brown bat?
An adult little brown bat weighs 7.15 g – 7.65 g and has a wingspan of 23.3 cm, according to values recorded on Wikidata.
Is the little brown bat endangered?
The little brown bat is listed as Endangered on the IUCN Red List, meaning it faces a very high risk of extinction in the wild.
How long does the little brown bat live?
The little brown bat has a recorded lifespan of 29 years.
How long is the little brown bat pregnant?
The recorded gestation period is 50 days – 60 days.
What kind of animal is the little brown bat?
The little brown bat (Myotis lucifugus) belongs to the family Vespertilionidae in the order Chiroptera.
Sources and how to cite this page
Data as of 2026-11-11. How this page is put together.
- An amniote life-history database to perform comparative analyses with birds, mammals, and reptiles · CC0 1.0 · E096-269
Myhrvold, N.P., Baldridge, E., Chan, B., Sivam, D., Freeman, D.L. & Ernest, S.K.M. (2015) An amniote life-history database to perform comparative analyses with birds, mammals, and reptiles. Ecology 96: 3109. https://doi.org/10.1890/15-0846R.1. Data: https://doi.org/10.6084/m9.figshare.3563457.v1 - Catalogue of Life eXtended Release · CC BY 4.0 · 2026-10-16 XR
Catalogue of Life (2026). Catalogue of Life eXtended Release, version 2026-10-16 XR. Catalogue of Life Foundation, Amsterdam, Netherlands. https://doi.org/10.48580/dgzlf - Wikimedia Commons · per file (CC0 / public domain / CC BY green, CC BY-SA amber, anything else not displayed) · 2026-11-11
Wikimedia Commons contributors. Wikimedia Commons. https://commons.wikimedia.org (each file credited to its author under its own licence). - EltonTraits 1.0: species-level foraging attributes of the world's birds and mammals · CC0 1.0 · 1.0
Wilman, H., Belmaker, J., Simpson, J., de la Rosa, C., Rivadeneira, M.M. & Jetz, W. (2014) EltonTraits 1.0: Species-level foraging attributes of the world's birds and mammals. Ecology 95: 2027. https://doi.org/10.1890/13-1917.1. Data: https://doi.org/10.6084/m9.figshare.3559887.v1 - Wikidata · CC0 1.0 · 2026-11-11
Wikidata contributors. Wikidata. https://www.wikidata.org (data retrieved via the Wikidata Query Service). - Wikipedia (English) · CC BY-SA 4.0 · 2026-11-11
Wikipedia contributors. Wikipedia, The Free Encyclopedia. https://en.wikipedia.org (text under CC BY-SA 4.0; each block names its article and revision).
Embed a card for this animal on your own site
Copy this code. The card shows the photo with its credit, key facts and a link back to this page.
CreatureData. (2026). Little brown bat (Myotis lucifugus). Retrieved from https://creaturedata.com/animals/little-brown-bat
“Little brown bat (Myotis lucifugus).” CreatureData, 2026, https://creaturedata.com/animals/little-brown-bat.
@misc{little_brown_bat_2026,
title = {Little brown bat (Myotis lucifugus)},
author = {{CreatureData}},
year = {2026},
url = {https://creaturedata.com/animals/little-brown-bat},
note = {Data as of 2026-11-11}
}