COSEWIC Status Reports

Technical Summary and Supporting Information for an Emergency Assessment of the Tri-colored Bat Perimyotis subflavus

Between 5.7 and 6.7 million bats, of several species, but mainly Little Brown Myotis, are estimated to have died in the last 6 years in the northeastern United States and eastern Canada. Tri-colored Bats are relatively rare in Canada and the response to White-nose Syndrome (WNS) by Little Brown Myotis is used as a surrogate for the response by Tri-colored Bat when information on Tri-colored is lacking. Mortality associated with White-nose Syndrome (WNS), caused by a fungus likely from Europe, has reduced populations of Little Brown Myotis by >75% in infected hibernacula, and this species has been modelled to be functionally extirpated (<1% population) in 16 years in the northeastern U.S. (Frick et al. 2010). There is strong evidence that the same result will occur in the Canadian population of Tri-colored Bat; significant declines and mortality events were recorded in Canada in 2011 and susceptibility to WNS is expected to be similar across most of Canada.


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Contact Person(s)

COSEWIC Secretariat
c/o Canadian Wildlife Service
Environment Canada
Ottawa, ON
K1A 0H3
Tel: 819-938-4125
Fax: 819-938-3984
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