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In Ontario, four bat species have been recently listed to the Endangered Species Act, 2007.  The listing is largely due to the spread of a fungus referred to as the 'White Nose Syndrome' which is caused by the Pseudogymnoascus destructans (PD for short) fungus.  PD primarily affects the bats during the hibernation period and is estimated to have killed 90 to 100 percent of bats at several hibernation sites.  In Ontario, the bats affected are: Little Brown Myotis (Myotis lucifugus), Nothern Myotis (Myotis septentrionalis), Tri-colored Bat (Perimyotis subflavus), and Eastern Small-footed Myotis (Myotis leibii).  Due to it's designation on the Endangered Species Act, 2007, those four species and their habitat are protected. 

When works are proposed within suitable summer roosting habitat - typically mature hardwood forests, studies are required to assess whether the habitat could support female maternity colonies.  These studies range from identifying suitable trees (i.e., cavity trees or snags) to collecting acoustic information.  Acoustic surveys are conducted during the month of June at which time recorders equipped with ultrasonic microphones are deployed in areas of suitable habitat (i.e., within clusters of cavity trees) during a period of 10 days.  The acoustic data is then collected, downloaded, and analysed by Ecologists to determine whether the forest in question supports Species at Risk Bats.  

Through the application of timing restrictions for tree removals and protection of key habitats, development can occur without harming these species.  

For more information on the White Nose Syndrome please visit

Bat Acoustic Data Collection 
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