In March, a Little Brown Bat (Myotis lucifugus) found alive near Seattle, Washington was diagnosed with White Nose Syndrome (WNS), a devastating fungal skin disease of bats caused by the fungus Pseudogymnoascus destructans. WNS was first diagnosed in New York in the winter of 2006/2007 and has swept across eastern and central North America, killing over 6 million bats in 28 US states and 5 Canadian provinces, threatening several species of North American bats with extinction. The detection in Washington is very concerning and puzzling as it marks a jump of more than 2000 km west of the previous westernmost confirmed case. For BC it is disturbing, for while bat research and WNS surveillance efforts were ongoing, we expected years before WNS came to the province and time to fully understand our bat population ecology before the disease threat was on our doorstep.
Since the unexpected diagnosis of WNS in Washington, members of BC BAT (BC Bat Action Team), a working group of non-governmental and governmental bat biologists and public educators, and members of the BC node of the CWHC, along with tremendous support from CWHC members from across Canada have been scrambling to do everything possible to understand and help protect BC’s bats from this threat.
The BC Community Bat Project, a network of 12 community bat projects across BC, has leapt into action. They are serving as the primary point of contact for the public through a toll free line; collecting incidental mortalities, coordinating and shipping them to the lab for necropsy and WNS testing, as well as educating and fielding calls from the public. Thanks to these efforts, since confirmation of the diagnosis of WNS in late March in Washington, 24 incidental mortalities, spanning 7 bat species, have been submitted to the lab. At the lab, a complete necropsy has been completed on every bat as well as rabies testing (by immunohistochemistry) and testing for P. destructans (by PCR). Twenty-two of these cases are negative for WNS to date and 2 are pending. The goal for this testing is to detect the entry of WNS into BC as soon as possible and use this information to attempt to slow the spread of this disease.
In addition to specimen collection and testing there are countless other initiatives underway by a number of people and groups in BC to try to improve the health of BC’s bats. This includes projects to determine the winter range of BC’s bats, collating current information on bat range, collaborating with cavers (Bats and Cavers project) to map bat use in caves, the creation of best management practices for cavers, wind energy and mining to decrease their impact on bat populations, the delivery of hygiene/decontamination protocols for bat researches, cavers and others visiting/working in underground bat habitats, and annual bat counts to determine baseline population counts.
No one knows what the consequences will be if, or more likely when, WNS reaches BC. British Columbia is home to the highest diversity of bats in Canada (16 confirmed species, with potentially one more that needs to be confirmed), including several species not currently within WNS range, so the susceptibility and consequences of infection in these species is unknown. The ecology of bats in BC is also quite different than in the east. We do not, to our knowledge, have the large hibernacula that are seen on the east coast; bats in BC tend to hibernate in smaller groups, and very few winter roosting sites are known. Having bats that hibernate in smaller groups may, hopefully, slow the spread of WNS. It will also make detection of WNS more difficult since monitoring large hibernacula for the mortalities and for the presence of the fungus is a key part of WNS detection in the east. In addition, some species of BC’s bats tend to rouse more frequently during the winter and some will even feed during these winter arousals, which may slow the growth of the fungus on the bats, and increase the bat’s resiliency to the disease.
If you are in BC and are interested in how you can help protect bats please visit http://www.bcbats.ca.
For more information:
https://www.whitenosesyndrome.org
http://www.cwhc-rcsf.ca/surveillance_data_wns.php
Submitted by Glenna McGregor – CWHC BC