New York Natural Heritage Program
Little Brown Bat
Myotis lucifugus (Le Conte, 1831)

Habitat [-]
The little brown myotis uses a variety of forest types and they are somewhat of a habitat generalist. They occur in deciduous, mixed, and coniferous forest stands. At a landscape-scale in New York, they are associated with habitats that have a higher composition of wetlands and shrub cover and lower amounts of agriculture (NYNHP unpub. data). They are known to occur at elevations up to 657 m (2,155 ft) in the Adirondacks during summer (Saunders 1988).

Little brown myotis frequently forage over wetlands and open water (Fenton and Barclay 1980; Broders et al. 2006). One study in Massachusetts found they used a variety of foraging habitats including an open-canopied reservoir, large ponds, and beaver meadows and closed canopy vernal pools; uplands and streams were used less often (Fenton and Barclay 1980).
During summer little brown myotis roosts in trees, buildings, under rocks, in piles of wood, and less frequently in caves (Fenton and Barclay 1980). Maternity roosts occur in hollow trees or in buildings that tend to have southwesterly exposure which creates warmer roost temperatures (Fenton and Barclay 1980).

In winter, little brown myotis hibernate in caves and mines in areas with high humidity and temperatures that are typically above freezing (Fenton and Barclay 1980). Their presence was positively related to mine entrance width and height in West Virginia (Johnson et al. 2006).

Associated Ecological Communities [-]
  • Allegheny oak forest
    A hardwood forest that occurs on well-drained sites in the unglaciated portion of southwestern New York. This is a forest of mixed oaks with a diverse canopy and richer ground flora than other oak communities in the state.
  • Appalachian oak-hickory forest
    A hardwood forest that occurs on well-drained sites, usually on ridgetops, upper slopes, or south- and west-facing slopes. The soils are usually loams or sandy loams. This is a broadly defined forest community with several regional and edaphic variants. The dominant trees include red oak, white oak, and/or black oak. Mixed with the oaks, usually at lower densities, are pignut, shagbark, and/or sweet pignut hickory.
  • Appalachian oak-pine forest
    A mixed forest that occurs on sandy soils, sandy ravines in pine barrens, or on slopes with rocky soils that are well-drained. The canopy is dominated by a mixture of oaks and pines.
  • Beech-maple mesic forest
    A hardwood forest with sugar maple and American beech codominant. This is a broadly defined community type with several variants. These forests occur on moist, well-drained, usually acid soils. Common associates are yellow birch, white ash, hop hornbeam, and red maple.
  • Chestnut oak forest
    A hardwood forest that occurs on well-drained sites in glaciated portions of the Appalachians, and on the coastal plain. This forest is similar to the Allegheny oak forest; it is distinguished by fewer canopy dominants and a less diverse shrublayer and groundlayer flora. Dominant trees are typically chestnut oak and red oak.
  • Hemlock-northern hardwood forest
    A mixed forest that typically occurs on middle to lower slopes of ravines, on cool, mid-elevation slopes, and on moist, well-drained sites at the margins of swamps. Eastern hemlock is present and is often the most abundant tree in the forest.
  • Limestone woodland
    A woodland that occurs on shallow soils over limestone bedrock in non-alvar settings, and usually includes numerous rock outcrops. There are usually several codominant trees, although one species may become dominant in any one stand.
  • Maple-basswood rich mesic forest
    A species rich hardwood forest that typically occurs on well-drained, moist soils of circumneutral pH. Rich herbs are predominant in the ground layer and are usually correlated with calcareous bedrock, although bedrock does not have to be exposed. The dominant trees are sugar maple, basswood, and white ash.
  • Mine/artificial cave community
    The biota of an abandoned mine or artificial underground excavation. Abandoned mines that are deep enough to maintain stable winter temperatures are important bat hibernacula. Mines, like natural caves, may be terrestrial or aquatic. Wells are also included here.
  • Oak openings
    A grass-savanna community that occurs on well-drained soils. In New York, these savannas originally occurred as openings within extensive oak-hickory forests. The best remnants occur on dolomite knobs.
  • Oak-tulip tree forest
    A hardwood forest that occurs on moist, well-drained sites in southeastern New York. The dominant trees include a mixture of five or more of the following: red oak, tulip tree, American beech, black birch, red maple, scarlet oak, black oak, and white oak.
  • Pine-northern hardwood forest
    A mixed forest that occurs on gravelly outwash plains, delta sands, eskers, and dry lake sands in the Adirondacks. The dominant trees are white pine and red pine.
  • Pitch pine-oak forest
    A mixed forest that typically occurs on well-drained, sandy soils of glacial outwash plains or moraines; it also occurs on thin, rocky soils of ridgetops. The dominant trees are pitch pine mixed with one or more of the following oaks: scarlet oak, white oak, red oak, or black oak.
  • Rich mesophytic forest
    A hardwood or mixed forest that resembles the mixed mesophytic forests of the Allegheny Plateau south of New York but is less diverse. It occurs on rich, fine-textured, well-drained soils that are favorable for the dominance of a wide variety of tree species. A canopy with a relatively large number of codominant trees characterizes this forest. Canopy codominants include five or more of the following species: red oak, red maple, white ash, American beech, sugar maple, black cherry, cucumber tree, and black birch.
  • Shallow emergent marsh
    A marsh meadow community that occurs on soils that are permanently saturated and seasonally flooded. This marsh is better drained than a deep emergent marsh; water depths may range from 6 in to 3.3 ft (15 cm to 1 m) during flood stages, but the water level usually drops by mid to late summer and the soil is exposed during an average year.
  • Spruce-northern hardwood forest
    A mixed forest that occurs on lower mountain slopes and upper margins of flats on glacial till. This is a broadly defined community with several variants; it is one of the most common forest types in the Adirondacks. Codominant trees are red spruce, sugar maple, American beech, yellow birch, and red maple, with scattered balsam fir.
  • Terrestrial cave community
    The terrestrial community of a cave with bedrock walls, including the biota of both solution caves (in limestone) and tectonic caves. Temperatures are stable in deep caves. Small or shallow caves may have a temperature gradient ranging from cold (below freezing) to cool (up to 50 degrees F). Although many caves have ice on the cave floor in winter, the ceiling is warm enough for a bat hibernaculum.
  • Vernal pool
    An aquatic community of one or more intermittently ponded, small, shallow depressions typically within an upland forest. Vernal pools are typically flooded in spring or after a heavy rainfall, but are usually dry during summer. Substrate is typically dense leaf litter over hydric soils. Vernal pools typically occupy a confined basin (i.e., a standing waterbody without a flowing outlet), but may have an intermittent stream flowing out of it during high water. This community includes a diverse group of invertebrates and amphibians that depend upon temporary pools as breeding habitat. These include amphibians, reptiles, crustaceans, mollusks, annelids, and insects.

Associated Species [-]
  • Big Brown Bat (Eptesicus fuscus)
  • Eastern Small-Footed Myotis (Myotis leibii)
  • Northern Myotis (Myotis septentrionalis)
  • Indiana Bat (Myotis sodalis)
  • Eastern Pipistrelle (Perimyotis subflavus)