IT WAS AN ODDLY WARM DAY in late February. Hibernating squirrels were out looking for food. Birds, too, began to twitter on the telegraph poles along the road. “At least you can still see these animals, but bats… even at night… you can’t see them” I murmured to myself while I was driving to meet up with Mike Scafini, endangered mammal specialist for the Pennsylvania Game Commission, to talk about Pennsylvania’s declining bat populations.
Mike greeted me right after I walked through the automatic door of the Pennsylvania Game Commission building. “How are you today?” he asked me, while giving me a warm handshake. Mike—a tall, somewhat slim, 34-year-old fella with thick beard, short hair, cotton shirt, and a pair of professor-style glasses—is a wildlife biologist for the PA Game Commission. His job is to manage all non-game mammals, such as northern flying squirrels, woodrats, and of course, bats, across the state of Pennsylvania.
The building of the PA Game Commission itself is quite interesting. Located on the edge of the state capital Harrisburg, the appearance of the building from the outside—medium sized, two floored, yellowish wall with red roof—doesn’t distinguish it much from other typical public buildings, say the DMV or middle school auditoriums. Only the sculptures of deer, and various flagpoles adorned with state and national flags, standing in front of the building seem to hint at the work going on inside by those working to protect our nature and animals. The inside, I realized, is a peculiarly harmonious combination of natural history museum, country pub, and the visitor center of a natural park—green carpet, a couple of wooden benches, deer heads hanging on the wall, wildlife taxidermy mounts, a canoe in the center of the lobby, a TV showing videos of animals, and exhibitions displaying law enforcement officer uniforms.
“When people think of the Game Commission,” Mike told me at the beginning of the interview, “they usually think of elk or deer or bear, but here, we actually are also in charge of small mammals that people don’t usually think of as Pennsylvania wildlife.”
“That’s why I am here today, to talk to you about bats,” I told Mike while nodding my head, as I agreed that most people I know had little awareness of these small creatures in their local environments.
THERE ARE NINE SPECIES OF BATS living in Pennsylvania: little brown bat, big brown bat, eastern pipistrelle bat, northern long-eared bat, Indiana bat, eastern small-footed bat, silver-haired bat, eastern red bat, and. Among the nine species, silver-haired, red, and hoary bats are migratory bats, meaning they, like some birds, will migrate to the south when winter approaches. The rest of the species are short distance hibernating bats—they don’t make long migratory trips when winter comes. Instead, they will hibernate in Pennsylvania or in adjacent states. The most common species in Pennsylvania nowadays, Mike told me, is the big brown bat. Therefore, when a person sees a bat here in Pennsylvania, it will most likely be the big brown bat.
For states like Pennsylvania, which depend heavily on agriculture, bats are extremely important for the economy. Bats are the state’s primary night-flying predator of insects and thus help protect us and agriculture from pests. Research shows, a single bat can forage as many as 500 insects in an hour, which equals to 3,000 insects every night.1 A colony of 150 big brown bats, which is the most common bat species in Pennsylvania, can consume 38,000 cucumber beetles, 16,000 June bugs, 19,000 stinkbugs, and 50,000 leafhoppers, and by devouring the adult beetles, they can also prevent the hatching of 18 million corn rootworms in a summer1.
“The Pennsylvania agriculture industry owes a lot to bats,” Mike said while pointing at a figure from a study published in Science in 2011 (by Justin G. Boyles and his team) and captioned, “Estimated economic value of bats to Pennsylvania farmers…Bats can save farmers $74 per acre—and millions of dollars each year—by eating bugs that can ruin a harvest.”
THE DESTINY OF HIBERNATING BATS in Pennsylvania, however, like the destiny of their peers in many eastern states across North America, has become catastrophic, because of a new bat disease called White-nose Syndrome. First discovered in February 2006, White-nose Syndrome has spread stormily across the east side of the United States and Canada, wiping out millions of hibernating bat population. According to Mike, White-nose Syndrome was first noticed in Pennsylvania around the winter of 2008 and 2009, and since then, the population of hibernating bats in Pennsylvania has dramatically declined.
“Off the six (hibernating) species (common in Pennsylvania),” Mike explained, “we have four of them close to or approaching ninety-nine percent declined.”
“Geez…ninety-nine percent?” I couldn’t believe what I had just heard.
“Yes…it’s a lot of bats.” He answered with frustration. Then he showed me another figure from surveys he conducted by comparing the winter bat species population from 2013 to 2016 with population counts of pre-White-nose Syndrome years at the same sites. In the graph, I could clearly see the populations of little brown, Indiana, northern long-eared, and tri-colored bats have almost declined one hundred percent.
“You can also see from the graph, each year, the number of bats has not rebounded,” Mike added.
THE FUNGUS THAT CAUSE White-nose Syndrome in bats is called Pseudogymnoascus destructans. This fungus is native to Europe but not to North America. Scientists have proposed that people who went to Europe for caving brought this fungus back to New York State. Hibernating bats infected with White-nose Syndrome will become irritated and dehydrated. They will wake up and fly out more often during the cold winter while there are no insects to eat, which becomes the primary cause of death for hibernating bats infected with White-nose Syndrome.
Although scientists have been working around the clock to find the cure of White-nose Syndrome for bats, the remedy still remains a mystery. Nevertheless, there are some new hopes recently discovered by scientists that might be able to end this disease for bats.
“There is actually an interesting experiment that is worth mentioning,” Mike said, “it’s called PEG-8000.”
PEG stands for polyethylene glycol, and it is a class of chemical compounds that have a wide range of medical, chemical, biological, and industrial uses. PEG-8000 is one specific type of PEG that can cause microbes to think that they are deficit of water, thus tricking them them into slowing growth. Plus, because PEG-8000 is non-toxic and chemically stable in fungi, it is considered as an ideal compound to stop White-nose Syndrome by hindering the growth of Pseudogymnoascus destructans—the fungus that causes White-nose Syndrome. Based on what Mike described, when scientists applied PEG-8000 to the wall of the roost, bats in the experiment were able to avoid picking up the spore of Pseudogymnoascus destructans. “This indicates PEG-8000 could be used as a roost cleaning application,” he added, “and being that bats are creatures of habits—they go back to the same spots in a cave in the winter. If we can treat these spots where bats congregate, we may have something.”
Along with the promise of this experimental remedy, PA government agencies such as the PA Game Commission has strictly implemented protocols released by the U.S. Fish and Wildlife Service to reduce the chance of their bat survey participants spreading this disease to bats when working in the field. “We are working closely with the U.S. Fish and Wildlife Service, and one big step was the decontamination protocol that they (U.S. Fish and Wildlife Service) put out,” Mike said. According to the newest (2016) version National White-Nose Syndrome Decontamination Protocol, individuals in contact with the bats or going into the hibernacula of bats is recommended to decontaminate their gear—an effective way to prevent the spread of the spores of the fungus—and these procedures are strictly followed by bat survey participants like Mike and many other scientists from the state government agencies.
Mike also told me that the Game Commission, too, is trying to work closely with the caving community to spread the word of which caves people should go into and which they should avoid, as well as implementing the decontamination guidelines to the caving community. “Most (caving) people don’t have any problems following the decontamination protocol,” Mike says. “Some caving groups are actually helping with bat surveys,” he added, “ they get to go caving and help to count the bats at the same time, and sometimes we even invite them to go into the cave and help out the survey.” To survey the bat population, Mike along with other bat scientists often enters dozens of sites each winter to count bats.
“So, do you consider yourself a good caver?” I asked.
“I’d say so.” Mike laughed with a blend of humbleness and confidence.
WHILE HIBERNATING BATS have been suffering from White-nose Syndrome, migratory bats are also not without life-threatening, human-caused threats. “Migratory bats are being hit by wind farms,” said Mike, who also did part of his master’s work in biology on surveying the mortality caused by wind farms. “Just an estimate of a thirteen-turbine wind farm was killing five hundred or more bats every summer.” He went on.
“Altogether—the wind farms for migratory bats and White-nose (Syndrome) for hibernating bats—are dramatically wiping out the PA bat population,” Mike added.
Mike’s concerns are important to consider as the United States is now one of the world’s leading producers of wind energy. Although wind energy is considered “good” energy for us, it might not be as “good” for flying animals. With tens of thousands wind turbines operating nowadays and a great number planed, the death of flying animals—not only bats, but also birds—have been increasing every year. According to American Bird Conservancy, the annual mortality of birds caused by wind turbines was estimated as high as 573,000 in 2012. And the Department of Energy predicts, if the U.S. meets its goal of 35% of the electrical power from wind energy, up to five million birds would be killed annually by the wind turbines. Therefore, despite the significance of producing clean energy with wind, people also need to find a solution to protect the flying animals being killed by wind farms!
While most of us currently don’t use wind farms energy, we can nonetheless also protect bats in our backyards. Not only just me, I believe many people have also wondered what to do with bats when they show up in our homes. “So, what can we do to save bats when they visit our homes?” I asked.
“Bats in homes is something we see more as a problem in the summer; essentially bats form maternity colonies (where female bats congregates to bear and raise the baby bats) during the summer to raise their pups.” Mike answered. In some cases they will try to set up a colony in your attic, or another warm, dark space. “When that happens, one option is that you can call us…and we can guide you though the process.” “The other option is what we call ‘eviction and exclusion’, where you can put a one-way door in the opening of the house so that bats can fly out the house but not back in…and once all the bats fly out you can seal the openings.” However, Mike also warned, the second option won’t work if there are flight-less pups in the colony—the adult bats fly out to feed the pup, and will try whatever way to get back to the house.
“If it is a single bat, you can wait for it to land on something and put a Tupperware over it and slice a piece of card board behind it and just take it out and release it on a tree.” Mike continued. “If it is a larger number of bats, we have what’s called NWCO, which is Nuisance Wildlife Control Operators…they know how to deal with bats.”
Time flies by quickly and, unwittingly, I have already spent almost an hour talking with Mike in the conference room. As I got ready to leave, I asked Mike what was his most unforgettable moment in his career as a bat scientist. His answer was, “to actually go into a cave for a winter survey and see thousands and thousands of bats, which was what it used to be like at the larger sites here in Pennsylvania.”
Mike walked me through that natural-history-museum, country-pub, and national-park-visitor-center-style Game Commission lounge and walked me out of the building. The weather was still oddly warm outside. On the way driving back to campus, I could still see squirrels climbing up the trees or birds twittering on the telegraph poles. But still, there were no bats. I was thinking about how after Mike showed me all the figures about bats he prepared for this interview, he had said with sadness, “ Yup… everything is going down…”
1 Data from Wildlife Outreach Center, Penn State Extension. http://extension.psu.edu/natural-resources/wildlife/wildlife-nuisance-and-damage/bats/a-homeowners-guide-to-northeastern-bats-and-bat-problems
Bat Conservation International: http://www.batcon.org
BIRD-SMART WIND ENERGY: PROTECTING BIRDS FROM POORLY SITED WIND TURBINES:
PennState Extension-Wildlife Nuisance and Damage-Bats:
Using a Novel Partitivirus in Pseudogymnoascus destructans to Understand the Epidemiology of White-Nose Syndrome: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5189944/
National White-Nose Syndrome Decontamination Protocol – Version 04.12.2016: