Bats of Colorado

There are approximately 20 species of bats found in Colorado. The reason this number is not completely known is because we are still documenting the range extents of some species. For example, we did not know that the Allen's big-eared bat (Idionycteris phyllotis) was in Colorado until acoustic recordings of its calls were documented in southwestern Colorado in 2008. We are still learning about the natural history, ecology, and habits of many species. This collaboration between bat biologists and climbers hopefully will help us answer some of these questions. Below is a list of the bat species of Colorado. Please follow the links to find out more about these amazing species. For more detail, visit the Colorado Bat Working Group website (

Family Vespertilionidae (evening bats)
The myotis
California myotis (Myotis californicus)
western small-footed myotis (Myotis ciliolabrum)
long-eared myotis (Myotis evotis)
little brown bat (Myotis lucifugus)
fringed myotis (Myotis thysanodes)
long-legged myotis (Myotis volans)
Yuma myotis (Myotis yumanensis)

The migratory tree-roosting bats
eastern red bat (Lasiurus borealis)
hoary bat (Lasiurus cinereus)
silver-haired bat (Lasionycteris noctivagans)

The pipistrelles
canyon bat (formerly western pipistrelle; Parastrellus hesperus)
tri-colored bat (formerly eastern pipistrelle: Perimyotis subflavus)

big brown bat (Eptesicus fuscus)
spotted bat (Euderma maculatum)
Townsend's big-eared bat (Corynorhinus townsendii)
Allen's big-eared bat (Idionycteris phyllotis)
pallid bat (Antrozous pallidus)

Family Molossidae (free-tailed bats)
Brazilian free-tailed bat (Tadarida brasiliensis)
big free-tailed bat (Nyctinomops macrotis)