Halloween is less than a week away. If you go trick or treating on Halloween, you’ll be sure to see vampires, werewolves, and other eerie creatures of the night. While most of these deserve their scary association, there’s one that’s been frequently misjudged: the bat. From controlling pests to pollinating plants, bats play a pivotal role in our ecosystem – saving the U.S. more than $3.7 billion each year alone in crop damage and pesticide costs. Now this misunderstood animal is in trouble.
Over the past decade, a catastrophic disease known as White-nose Syndrome (WNS) has been ravaging bat populations across North America. Bats with WNS develop a white fungus that grows around their faces and body as they hibernate during the winter season. It’s during this hibernation period that WNS becomes deadly as the affected bats must deplete their fat reserves and energy – collected during their pre-hibernation foraging – to fight off the disease and ultimately are unable to survive the winter.
According to one recent study, WNS has destroyed more than 90 percent of three North American bat populations: the Northern Long-Eared, Tri-Colored, and Little Brown Bat. Each of these species are endangered or proposed to be added to the endangered species list by the U.S. Fish and Wildlife Service.
In addition to its harmful impact on our environment and agriculture, WNS also has implications for U.S. energy companies. As these bat species become federally threatened or endangered, energy companies looking to build any new assets in forested habitats will need to attain special permits and approvals – frequently at a much higher cost. Additionally, energy companies could be restricted to specific times of year at which they can build assets and manage vegetation. The overall increase in resources and planning needed could slow down energy providers’ operations and ability to meet regional and national clean energy goals.
In light of this growing concern, EPRI is spearheading efforts to address the spread of WNS. Research shows that bats entering hibernation with larger fat reserves tend to fare better against WNS and are less likely to die of starvation during hibernation. As a result, in 2019, EPRI and Bat Conservation International (BCI) launched the “Fat Bats” program to study if artificial prey patches – a non-invasive and cost-effective measure – could help “fatten” bats to increase their survival chances during the winter.
Initially, the program focused on bat hibernation areas in Michigan’s upper peninsula to see if installed feeding stations had an impact on an observable sample size of bats. Upon review, the stations – which used ultra-violet (UV) lights to attract insects – were found to be effective and helped increase bats’ pre-hibernation foraging activity. Stemming from these positive results, EPRI and BCI expanded the Fat Bats program beyond Michigan and constructed artificial prey patches in other U.S. regions and habitats affected by WNS.
Ultimately, the success of the Fat Bats program depends on it being a scalable solution for bat populations nationwide. As such, researchers agreed on several guidelines for installing new feeding stations to ensure efficacy and consistency. For one, using broad spectrum blue-white lights with high UV content in prey patches would provide the best light source for attracting insects. Additionally, the placement of prey patches should not interfere with other wildlife or bats’ normal behavior.
With the bat hibernation period now upon us, researchers are hoping to have insight into the effectiveness of these expanded prey patches by early next year. If the findings are similar what was seen in Michigan, it will mean a short- and long-term solution to helping bat populations fight off and recover from WNS.
(PHOTO: Deployment of a UV fluorescent light in the forest within 200 m of a known bat overwintering site where WNS-susceptible bats are known to gather for fall swarm and winter hibernation. )