Surveillance Strategy for Detecting Pseudogymnoascus Destructans (PD) and White-Nose Syndrome in Montana 2016-2017

Abstract

The devastating bat disease, White-Nose Syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd), was detected in western Washington state in March of 2016.  This detection was 1,300 miles from the previous westernmost detection and highlighted the urgency for surveillance in other western states like Montana.  Early detection of the disease may provide valuable insights into the statewide status of WNS, research opportunities, mitigation options and cave management.  The goals of Montana’s surveillance plan include 1) surveying for WNS/Pd in new geographic areas outside the WNS-affected zone and/or biologically important sites and 2) surveying for WNS infection in bat species that are not currently known to be susceptible.  In the absence of information or a risk assessment to help Montana focus on priority surveillance areas other than winter hibernacula, the 2017 strategy focuses on sampling at six hibernacula representing all regions where aggregations of bats overwinter.  Both active and passive sampling of bats and hibernacula environments will be conducted.  Active sampling can detect Pd from swabs of bats or in hibernacula soils.  Passive sampling will be conducted into the early summer specifically targeting bats found dead outside of hibernacula, bats showing clear signs of WNS infection, and bats found dead as part of a large mortality event.  Bats submitted for rabies testing may also be sampled when circumstances or characteristics of the carcass indicate WNS may be the cause of mortality.  While surveillance efforts can be costly it may provide information with enough time to better inform decision making.