Tackling White Nose Syndrome in New Mexico

Click here to watch a video about this science-driven management effort. Credit: BLM 

Bat Week in October builds on the long association of bats with Halloween and other celebrations of the dead. But bats aren’t the terrifying creatures of legend. In fact, they provide essential services to nature and humans by controlling pests and helping pollinate dozens of species of plants. 

What’s truly terrifying is the biggest threat to bats. It’s a disease called white-nose syndrome that began infecting hibernating colonies in the northeastern United States in 2006 and spread westward. The disease is caused by a fungus (Pseudogymnoascus destructans), which originates from caves in Europe. Scientists are unsure how the fungus got to the United States, though the most likely source is from humans who inadvertently transferred spores.  Unlike European bat species, bats in the U.S. have no immunity to the toxic effects of the fungus. 

By 2010, scientists detected white-nose syndrome in populations west of the Mississippi River, with mortality rates often as high as 100%. The threat now reaches to two caves in eastern New Mexico. 

The fungus produces large numbers of spores that can persist and remain viable in environments where bats hibernate. Bats can transmit it to each other or pick it up from the surrounding environment. Humans carrying spores into caves on clothing and gear may inadvertently spread it, too. In 2011, the U.S. Geological Survey recommended implementation of standard procedures known as “universal precautions” to reduce disease transmission and spread, including decontamination protocols, gear, and equipment restrictions, and limitation of access to sensitive environments. 

With management responsibilities for some 500 caves representing potential bat winter habitat, BLM-New Mexico land managers and biologists knew they needed to act quickly to protect bat populations. They turned to scientific research and expertise on the disease. 

Limiting the natural movement of bats is not feasible, and there remain no existing practical treatments for bat hibernation sites or infected bats. So BLM-New Mexico monitors bat populations for the disease.  

More than half of the 29 bat species native to New Mexico hibernate in the winter and therefore may be susceptible to the disease. After extensive public comment, BLM temporarily closed 28 caves for an initial period of two years, starting in January 2011, extending closures for caves that are biologically significant bat roosts, such as the Fort Stanton Cave in the Fort Stanton-Snowy River Cave National Conservation Area.  Researchers may enter with special recreation permits and are subject to decontamination procedures verified by the U.S. Fish and Wildlife Service. 

Research subsequently conducted in BLM-New Mexico caves suggested that eight of nine western bat locations studied have the appropriate temperatures and humidity for the growth and persistence of the infecting spores.  

Although researchers have made significant strides in understanding the disease, managers continue to lack information on how best to control its spread. Still, by relying on scientific evidence and principles, BLM land managers and biologists have slowed the spread of the disease and kept it out of most caves important to bats in the state. They hope to apply new research to continue to improve management and conservation of these incredible species.