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Little Brown Myotis

Little Brown Myotis

Little Brown Myotis (Myotis lucifugus)

Status: Endangered

The Little Brown Myotis, also known as the Little Brown Bat, is the most common bat found in Canada. In fact, it is found in every province except Nunavut. These nocturnal hunters prefer to live by bodies of water and spend their days sleeping in day roosts and their nights hunting for their favorite insects, which can include moths, wasps, beetles, gnats, mosquitoes, midges and mayflies. Bats will typically begin their hunt at dusk and Little Brown Myotis can be seen swooping over the water and in and out of vegetation. They use several strategies to catch prey including plucking them from the water’s surface to scooping them up with their wings or tail, then transferring it to it’s mouth. These bats typically weight about 8 grams (that’s the weight of 2 nickels and a dime!) and can eat 50 – 100% of their body weight in one night! As the temperature starts to cool in the fall, Little Brown Myotis will move to hibernation roosts, sometimes traveling hundreds of kilometers. Here they remain with hundreds of other Little Brown Myotis, huddled together to hibernate for the winter. This is one of two Canadian species of bats that will roost in man-made structures, putting them in close proximity to humans. The disturbance of a hibernating bat roost can have detrimental effects on the bats ability to survive the entire winter, thus reducing bat populations. But at this time the bat’s biggest foe is not humans. A fungus that causes White Nose Syndrome is decimating bat populations all over North America. It appears as a white dusting on the bats face and body. The fungus is thought to disrupt the bats ability to hibernate, often causing them to wake and leave the roost in the middle of winter. Without enough energy reserves to last the winter, the bats do not survive until spring. It is estimated that 94% of the population in eastern Canada have died from White Nose Syndrome. Scientists are racing against the clock to find a way of stopping the spread of the fungus. You can help by not disrupting or entering bat roosts. The fungus from infected roosts can be carried to uninfected area on shoes and clothing. You can also, cautiously, help roosting bats if they decide your attic or barn looks like a cozy place to bed down for the winter. If possible, try not to disturb them and come spring you may find them paying back your kindness with an insect free yard.