White-nose syndrome (WNS) is a disease caused by a cold-loving fungus, Pseudogymnoascus destructans, that has killed more than five million bats in the eastern United States and Canada since 2007. White-nose syndrome has caused extremely high mortality in six bat species, including the endangered Indiana bat. The disease presents a high risk to additional bat populations and there is a strong possibility of its spreading to bat populations in western states. Bat population declines due to WNS may result in substantial ecological, economic, and management costs for the country. The value of bats to the agricultural industry is estimated at $23 billion per year.
Forest Service Research and Development is a leader in fungal pathology, invasive species control, monitoring design, and bat ecology and is collaborating with diverse partners to control the spread of the WNS fungus and reduce disease-induced mortality. Specifically, we are working in the following areas.
Bat Ecology, Genetics, and Demographics — We have completed range-wide analyses of the effects of WNS to bat populations, their genetic diversity and viability, and their requirements for conservation.
- Wildlife biologist Sybill Amelon is currently evaluating genetic viability of the Indiana bat based on current population losses. Preliminary population analyses suggest this species may have reduced genetic diversity before WNS, so that high mortality from WNS in the Northeast will make this species particularly vulnerable. Using hibernacula count data and models, she has estimated population trajectories for four WNS-affected bat species. Cumulative declines in regional relative abundance by 2011 from peak levels range from 30 to 71%. With partners, a conceptual model of the WNS disease cycle has been developed.
- With university collaborators, Deahn Donner and Paula Marquardt are currently developing landscape genetics approaches to identify disease-resistant populations that can be targeted for conservation efforts. This approach, along with acoustical monitoring, will reveal movement patterns between wintering hibernacula and summer roosting sites to help bat populations naturally expand after WNS exposure.
- Research ecologist Susan Loeb leads the North American Bat Monitoring Program, which provides the statistical and logistical architecture for coordinated bat monitoring. This program supports local, regional, and range-wide inferences about trends in bat distributions and abundances in response to WNS, climate change, wind energy development, and habitat loss. Results from this program will provide managers and policy makers with the information they need on bat population trends to be effective when managing bat populations, detecting early warning signs of population declines, and estimating extinction risk.
Evaluation of Pathogen Genetics — Mycologists Daniel Lindner and Jessie Glaeser have genetically identified the WNS fungus as Pseudogymnoascus destructans, which led to the development of the most accurate and sensitive DNA technique for detecting the fungus in samples from almost any source. The technique is 100-fold more sensitive than previous methods and facilitates detection of the fungus before the clinical disease is observed, setting the new standard used to survey samples anywhere in North America.
Genetic Control of Pseudogymnoascus destructans — Analysis of the fungi in bat hibernacula allowed scientists to characterize factors that differentiate Pseudogymnoascus destructans from non-pathogenic relatives. The analysis will help with the creation of informed management and mitigation plans. Lindner and his fungal genetics collaborators are working on identifying virulence genes of Pseudogymnoascus destructans and the potential to “turn off” these genes. Genetic transformation systems have been developed, genomes of non-pathogenic near relatives have been sequenced, and the identification of the virulent genes is underway.
Bacterial Control of Pseudogymnoascus destructans — With university collaborators, Sybill Amelon has investigated compounds derived from naturally occurring soil bacteria for inhibiting growth of Pseudogymnoascus destructans on bat species. She has also conducted exposure trials to evaluate effects of soil-bacteria-derived volatile substances on bat species with positive results.
Supports to Land Managers -— Bat biologists are using this research to devise strategies to save these animals from extinction. Publications to share this knowledge include a Northern Research Station summary National Interagency Team Mobilizing To Tackle White-Nose Syndrome of Bats and an overview of the current knowledge about WNS geared for land managers by wildlife biologist Roger Perry.
The Forest Service worked with the U.S. Fish and Wildlife Service in preparing the National Plan for Assisting States, Federal Agencies, and Tribes in Managing White-Nose Syndrome in Bats, and a subsequent White-Nose Syndrome national implementation plan through interagency work groups. In addition, the Forest Service developed the USDA Forest Service Science Strategy for Protecting Bats From White-Nose Syndrome to address the need to expand and coordinate in-house expertise in applied science and transfer research into on-the-ground management strategies. The strategy focuses on Forest Service research capabilities to detect the fungus, reduce the spread, and recover bat populations, in support of the WNS National Plan.