Species at Risk Feature - Little Brown Bat

The Little Brown Bat (Myotis lucifugus) is one of just 18 species of bat found in Canada with the largest distribution of them all. A nocturnal, echolocating insectivore, the little brown bat measures 8-10 cm in length, weighing only a mere 5-14 grams. They range in colour from brown to red-brown, and golden-brown, with female bats presenting as larger than male bats. 

Little Brown Bats are very important insectivores, as they serve as a natural method of biocontrol for controlling several ‘nuisance’ insect species such as moths and mosquitoes, eating large quantities of insects at each feeding. They play a significant role in the reduction of mosquito populations, especially around their roosting sites, eating as much as their own weight in insects in one night’s feeding.

Little Brown Bats were listed as Endangered by COSEWIC in November 2013. In Canada alone, 50% of the global range of the little brown bat is found within Canada in all provinces (excluding Nunavut). The population of little brown bats in Canada has seen a rapid decline resulting from the deadly White-Nose Syndrome, a fungal disease that has wiped out around 94% of hibernating bats in Eastern Canada alone. This contagious and fatal disease is expected to reach the entire Canadian population over the next decade and will have dangerous implications for the remaining little brown bat populations throughout the rest of Canada. 

White-Nose Syndrome alone is the largest contributing factor to the dramatic decline in the little brown bat populations, but their numbers continue to be threatened by human interference. These threats include habitat loss and degradation from human activities and infrastructure, the use of pesticides on their prey species, pollution, and more. 

Some of the ways that we can help support Canada’s Little Brown Bat populations are similar to the ways that you can help all bird species: through the continued condemnation of the use of pesticides and insecticides as a means of wiping out insect populations that make up the entirety of insectivore diets. By researching sustainable and environmentally conscious methods of biocontrol for controlling the presence of insect species, we are reducing the risk of destroying the food source that these species rely on. In addition to this, the active protection and recording of bat roosts and nesting sites are instrumental in aiding in the protection and monitoring of our Canadian bat populations. When encountering a bat in a building or in your home, the best thing you can do is call a professional, rather than an exterminator, so the bat can be safely returned to the wild. In many cases, bats are misunderstood and carry a stigma surrounding zoonotic disease transmission and level of danger when handling. With proper and thorough research, it is possible to coexist with bats without fear of harm to humans or bats. The protection of these individuals can lead to greater success within the rest of the bat community through their safe return back to the wild.

Other ways that you can support the success of local bat populations are through the creation of double-chambered bat boxes/houses to help combat their habitat loss and to prevent bats from roosting in houses and buildings. There are many online sources to retrieve blueprints to make your own bat box at home or many local stores and businesses where you can purchase one ready to go! If you’re located in Saskatchewan, check out the websites of Living Sky Wildlife Rehabilitation, Meewasin Valley Authority and the Wildlife Rescue Society of Saskatchewan (WRSOS) for more information on bats and how you can help their populations thrive. 

Lastly, monitoring the number of little brown bats found throughout Canada, including where active roosting sites are, can allow scientists and researchers to document and study local populations in order to follow and track White-Nose Syndrome in order to monitor its spread throughout the rest of Canada. 

To learn more about Little Brown Bats, local populations within the Prairies, and ways that you can take action to protect these important nocturnal insectivores, follow the links below! :)


The bat seekers of Nova Scotia | CBC News

NCC: Little brown bat (natureconservancy.ca)

Little Brown Bat | National Wildlife Federation (nwf.org)

Meet the Little brown bat - Bat Conservation International

Hinterland Who's Who - Little Brown Bat (hww.ca)

Local Chapter: