Species Spotlight: Tri-colored Bat
To celebrate the run up to Halloween, we want to shine the moonlight on each of the eight bat species of Ontario. In this series of blog posts, we will be highlighting the key info for each species and will provide some exclusive recordings we have collected this year in our Batacea Guelph Bat Watch project.
In this post, we will be spotlighting the tri-colored bat (scientific name: Perimyotis subflavus).
The tri-colored bat (formerly known as the eastern pipistrelle) has pale brown fur, weighs ~7 grams and has a wing span averaging 23 centimetres. Its muzzle, forearms and ears are orange-red and the sides of its wings and body are dark brown. The name 'tri-colored' comes from the fact this species has black, yellow and brown hairs on its back.
Range and Ecology
Tri-colored bats can be found on the east of Canada, specifically in Ontario, New Brunswick, Nova Scotia and Québec. This species is associated with forested habitats, similar to the northern myotis, and they feed over water and in forest clearings on a variety of flying insects, such as beetles, flies and moths.
During the summer months, tri-colored bats can be found roosting on the branches of trees and in the winter months they roost in caves/mines (hibernacula).
Below is a video we took of tri-colored bats feeding in a forest clearing.
This species is currently classified as 'Vulnerable' according to the IUCN Red List, with decreasing long-term population trends. Similar to the little brown bat and northern myotis, tri-colored bats have been severely affected by white-nose syndrome (WNS). The tri-colored bat’s Canadian range falls completely within the current known range of WNS, and as a result, the risk of localized extinction (extirpation) for this species is higher than that of little brown bat and northern myotis. Other issues, including loss of forest cover, chemical contamination and loss of roosts through human removal also threaten this species.
Throughout our 2020 summer surveys, tri-colored bats were recorded at our heavily forested site, making up 5.8% of the total number of recordings for 2020.
Spectrograms from tri-colored bats typically range between ~70-40 kHz, with an abrupt transition between vertical and horizontal components. The horizontal component is largely flat and often above 40 kHz.
To listen to the tri-colored bat call snippet above, download the MP4 file below.
To explore more tri-colored bat spectrograms, check out the iNaturalist Bat Spectrogram project.
Read our northern myotis, eastern red bat, little brown bat, silver-haired bat, big brown bat and hoary bat species spotlights on the Batacea blog page and keep an eye out for our final species spotlight on 31st October.