After bushwhacking his way up a steep, rocky slope forming one side of a narrow hollow in Kanawha State Forest, Jesse De La Cruz reached a small, long-abandoned mine portal, into which he plunged his arm.
“Not much cool air movement,” he said, indicating that the site is likely unsuitable for his mission.
“There’s a bigger one on uphill, if I can find it,” said Doug Wood, a member of the Kanawha State Forest Coalition, who had volunteered to help De La Cruz with his work — setting up mist nets at the entrances to abandoned deep mines most likely to contain bats.
The bats De La Cruz, a research associate at Virginia Tech’s Conservation Management Institute, hopes to capture and release are northern long-eared bats, a species among the hardest hit by white nose syndrome, a deadly fungus-borne malady.
Millions of North American bats have died from white nose syndrome since it was first observed in caves near Albany, New York, in 2006, and quickly spread westward, reaching West Virginia by early 2009. Since then, WNS has spread as far west as the state of Washington and northward into Canada.
In some northeastern states, where WNS been around the longest, up to 99 percent of the northern long-eared bat (NLEB) population has been wiped out by the fungus. The species’ population had been stable prior to the arrival of WNS. Surveys of West Virginia hibernation caves several years after WNS first turned up here produced very few healthy NLEB specimens.
By 2015, the die-off had become severe enough for the U.S. Fish and Wildlife Service to list the NLEB as a threatened species.
While NLEBs historically shared hibernation caves with other bat species, they did so in relatively small numbers, as they are more solitary than most bats. The threatened bats are also known to hibernate in small groups or as individuals in abandoned underground coal mines, cracks and crevices in cliffs and boulders — even in railroad tunnels and culverts.
On a recently updated U.S. Fish and Wildlife Service fact sheet on the NLEB’s listing as a threatened species, it was noted that in areas where WNS has been present for three or more years, NLEBs “are often extirpated or are found at extremely low numbers during winter [hibernation cave] surveys.”
“However,” the fact sheet continued, “they continue to be found during summer in some WNS affected areas, though in very low numbers. Numbers observed in some areas of West Virginia and at some coastal sites suggest that there may be scattered areas where this species has not been as severely impacted as other areas of eastern North America.”
“Here in West Virginia, more northern long-eared bats are being captured than in all the other 12 states in the Fish and Wildlife Service’s Northeastern Region combined,” De La Cruz said.
A West Virginia native who earned his master’s degree at WVU, De La Cruz’s current northern long-eared bat trapping work is part of a research project funded by the U.S. Fish and Wildlife Service.
By identifying coal mines in which NLEBs hibernate, De La Cruz and other researchers will be able capture and track the bats to their summer maternity areas, “which allows us to collect genetic material to examine relatedness between bats captured at mines and those from maternity areas,” he said.
Most mortality from WNS takes place in hibernation caves, where the fungus, believed to be spread by bat-to-bat contact, attacks the skin of inactive bats and causes them to exit the hibernation state prematurely. By flying about in an attempt to hunt insects that aren’t present during winter, the affected bats burn up their fat reserves, weaken and die.
Crowd-avoiding NLEBs have long been known to use abandoned coal mines as alternatives to hibernation caves, and West Virginia has an abundance of empty deep mines and mine portals, many of them found not far from hibernation caves.
“Is this why these bats remain prevalent in West Virginia?” De La Cruz asked.
That’s one question he hopes his research will answer.
More answers could come from identifying coal mines in which NLEBs hibernate.
De La Cruz and other researchers will be able to capture and track the bats to their summer maternity areas, “which allows us to collect genetic material to examine relatedness between bats captured at mines and those from maternity areas,” he said.
Occupied mines could also be studied to determine “why bats may find refuge in mines in a post-WNS world,” he said. One hypothesis is that the lack of soil and organic matter in mines could inhibit WNS growth, as could the acidity of water found in such mines.
Previous bat survey work in north-central West Virginia by De La Cruz and other researchers suggests this region may contain the largest populations of NLEBs, according to the Virginia Tech researcher.
“I’ll be heading north and sampling on public land across West Virginia after I leave here,” he said.
De La Cruz is familiar with Kanawha State Forest, its bats and its mine portals.
In 2015, the Kanawha State Forest Foundation, Mary Draper Ingles Trail Blazers and Kanawha Trail Club contracted him to conduct a bat survey involving several KSF mine portals in close proximity to the KD No. 4 surface mine, then operating on land adjacent to the forest. A healthy female NLEB turned up in his mist net. It could have been used by foes of the mine to leverage enforcement of laws protecting the habitat of threatened species, but the mine was ordered closed the following year following a series of permit violations.
More than a century ago, dozens of deep mines operated in what is now Kanawha State Forest.
Last week, De La Cruz, assisted by Wood and other volunteers, conducted a mist net survey at the mine portal where the NLEB was captured in 2015, as well as an abandoned mine portal in KSF a few miles away, but made no captures.
But he plans to return to complete the KSF survey.
“Hopefully, we’ll have better luck in a couple of weeks,” he said.