“Endangered” means the species lives in the wild in Ontario but is facing imminent extinction or extirpation.

Date added to the Species at Risk in Ontario List

June 15, 2016

Read the assessment report (PDF)

What it looks like

The Tri-colored Bat is a small pale brown bat that weighs about 7 gm (the weight of a two dollar coin) and has a wingspan of 23 cm. The muzzle, ears and forearms are orange-red while the sides of the body and wings are dark brown. The Tri-colored Bat is named for the hairs on its back which are black, yellow and brown. It was formerly called the Eastern Pipistrelle.

Where it lives

During the summer, the Tri-colored Bat is found in a variety of forested habitats. It forms day roosts and maternity colonies in older forest and occasionally in barns or other structures. They forage over water and along streams in the forest. Tri-colored Bats eat flying insects and spiders gleaned from webs. At the end of the summer they travel to a location where they swarm; it is generally near the cave or underground location where they will overwinter. They overwinter in caves where they typically roost by themselves rather than part of a group.

Where it’s been found in Ontario

This bat is found in southern Ontario and as far north as Espanola near Sudbury. Because it is very rare, it has a scattered distribution. It is also found from eastern North America down to Central America.

What threatens it

Tri-colored Bats are threatened by a disease known as white nose syndrome, caused by a fungus which is believed to have been inadvertently brought from Europe to North America.

The fungus grows in humid cold environments, such as the caves and mines where Tri-colored Bats hibernate.

The syndrome affects bats by disrupting their hibernation cycle, so that they use up body fat supplies before the spring when they can once again find food sources.

It is also thought that the fungus affects the wing membrane, which helps to maintain water balance in bats. Because of this, thirst may wake bats up from hibernation, which may be why those infected with white nose syndrome can be seen flying outside caves and mines during the winter.

Bats at more than three quarters of Ontario’s hibernation sites are at high risk of disappearing due to white nose syndrome. Mass die-offs mean that there are no individuals left to reproduce.

Action we are taking

Endangered species and their general habitat are automatically protected.

Recovery strategy

A recovery strategy advises the ministry on ways to ensure healthy numbers of the species return to Ontario.

Read the executive summary and the full document (December 5, 2019).

Government response statement

A government response statement outlines the actions the government intends to take or support to help recover the species.

Read the government response statement (September 8, 2020)

What you can do

Report a sighting

  • The Ministry of Natural Resources and Forestry tracks species at risk such as the Tri-colored Bat. You can use a handy online form to report your sightings to the Natural Heritage Information Centre. Photographs with specific locations or mapping coordinates are always helpful.


  • Volunteer with your local nature club or provincial park to participate in surveys or stewardship work focused on species at risk.

Be a good steward

  • Private land owners have a very important role to play in species recovery. You may be eligible for stewardship programs that support the protection and recovery of species at risk and their habitats.
  • The Canada-Ontario Farm Stewardship Program is available to farmers registered under the Canada-Ontario Environmental Farm Plan to encourage greater protection and conservation of habitat for species at risk.
  • Consider building a bat box for your property; learn more about how to build one and where to set it up.
  • Don’t visit caves when bats may be present. You can accidentally spread the White Nose Syndrome fungus or cause the bats to arouse unnecessarily.

Report illegal activity

Quick facts

  • The Tri-colored Bat usually hibernates in the deepest recesses of a cave where temperatures are more uniform and the walls are the warmest.
  • Its day roosts are sometimes in clusters of dead leaves on deciduous trees. As many as 18 individuals may roost together.
  • It may make short distance migrations of a few hundred kilometres between their summer roosts and winter hibernacula.