New York Natural Heritage Program
Tri-colored Bat
Perimyotis subflavus (Menu, 1984)

Habitat [-]
Tri-colored bats over-winter in humid areas deep within caves and mines with a constant temperature of around 52-55F (Griffin 1936; Godin 1977). A study in Arkansas found tri-colored bats selected larger caves with a wide range of temperatures within a season, but little variability among temperature between seasons (Briggler and Prather 2003). Surveys of hibernacula in New York conducted by the New York State Department of Environmental Conservation found tri-colored bats segregated from other species in warmer areas of the cave with high humidity.

Wooded riparian areas are likely an important foraging habitat for this species during the summer. One study in coastal South Carolina, found that tri-colored bats were more frequently found in riparian areas than in upland sites and especially, riparian areas that were wooded or highly vegetated (Menzel et al. 2005). They may also forage in woods or along waterways or forest edges (Fujita and Kunz 1984). Although tri-colored bats are typically considered a clutter-adapted species capable of foraging within forested areas, they also forage over early successional and open habitats (Loeb and O'Keefe 2006).

Tri-colored bats may roost in habitats including open woods near water and they may select roosts in buildings, crevices of cliffs and rocks, or in or below the canopy of live or recently dead trees that retain some dead or live leaves (Veilleux et al. 2003; Carter and Menzel 2006; Perry and Thill 2007). They are occasionally reported from caves during the summer (Godin 1977), and have been known to form maternity colonies in barns (Fujita and Kunz 1984), in clusters of dead leaves in oaks or pines (Perry and Thill 2007), and in Nova Scotia in lichen (Poissant et al. 2010). Perry et al. (2008) found that tri-colored bats tended to select roosts that were away from roads, in unharvested woods with high habitat heterogeneity, or in the unharvested riparian buffer of a partially harvested stand. Some habitat characteristics may vary regionally. Perry and Thill (2007) found tri-colored bats in mature forest stands with a hardwood component and a complex vertical structure and dense midstory. However, Yates and Muzika (2006) found that tri-colored bats favored open habitats with less dense mid-story vegetation and a dense understory.

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.
  • 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-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.
  • 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.
  • 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.

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