little brown bat

mammal

Also known as: Myotis lucifugus

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Last updated

July 23, 2026

Quick Summary

The little brown bat (Myotis lucifugus) is a small, insectivorous mammal native to North America. It is a type of vesper bat, a group found worldwide. These bats typically measure about 3.5 to 8 cm (1.4 to 3.1 inches) in length, excluding their tail, and weigh between 5 and 45 grams (0.2 to 1.6 ounces). Little brown bats are known for their brown fur and are among the most widespread land mammals. They play a role in controlling insect populations. Unfortunately, these bats are susceptible to white-nose syndrome, a fungal disease that has caused significant mortality among bat populations in North America.1234

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brown bat
…80 species, among them the little brown bat (M. lucifugus) of North America and the large mouse-eared bat (M. myotis) of Europe. Members of the genus are about 3.5–8 cm (about 1.4–3.1 inches) long without the 4–6-cm (1.6–2.4-inch) tail and weigh about 5–45 grams (0.2–1.6 ounces). Apart from humans, they…
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…80 species, among them the little brown bat (M. lucifugus) of North America and the large mouse-eared bat (M. myotis) of Europe. Members of the genus are about 3.5–8 cm (about 1.4–3.1 inches) long without the 4–6-cm (1.6–2.4-inch) tail and weigh about 5–45 grams (0.2–1.6 ounces). Apart from humans, they…
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bat
Life cycle
…several big brown (Eptesicus fuscus), little brown (Myotis lucifugus), and greater horseshoe bats (Rhinolophus ferrumequinum) that have lived more than 20 years, and a few have lived more than 30. Probably many bats in temperate climates live more than 10 years. Longevity has not been established for most tropical species,…
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…several big brown (Eptesicus fuscus), little brown (Myotis lucifugus), and greater horseshoe bats (Rhinolophus ferrumequinum) that have lived more than 20 years, and a few have lived more than 30. Probably many bats in temperate climates live more than 10 years. Longevity has not been established for most tropical species,…
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white nose syndrome
Future impacts and management
…syndrome was detected included the little brown bat (Myotis lucifugus), the endangered Indiana bat (M. sodalis), and the big brown bat (Eptesicus fuscus). The disease has since been detected in other species, several of which are endangered. However, more than 20 bat species found in the contiguous United States and…
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…syndrome was detected included the little brown bat (Myotis lucifugus), the endangered Indiana bat (M. sodalis), and the big brown bat (Eptesicus fuscus). The disease has since been detected in other species, several of which are endangered. However, more than 20 bat species found in the contiguous United States and…
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