Long days in urban bat outreach

Bat walk led by Amanda Bevan, Urban Bat Project, Organization for Bat Conservation in Pontiac, Michigan.  Credit: Organization for Bat Conservation.

Amanda Bevan is busy and for her, that’s a good thing.

As the Organization for Bat Conservation’s Urban Bat Project Leader, Bevan educates city folks about the importance of bats, and if she’s busy, it means people are aware of the decline of bats due to white nose syndrome (WNS) disease and want to help.

With the help of a U.S. Fish and Wildlife Service WNS grant, Bevan organizes conservation and outreach partnerships in 10 cities in Michigan, Illinois, Indiana, Wisconsin, Tennessee, New York, Minnesota, Ohio and the District of Columbia. She says she hopes to expand the project to other cities in the future with additional funding.

Partners include a Milwaukee horticultural society, Columbus Audubon, Illinois State Museum,  a District of Columbia Fisheries and Wildlife Division bat biologist, high school teachers and students, bat researchers and horticulturalists like those at the New York Botanical Gardens.

They set up warm, safe bat boxes made from upcycled Chevy Volt battery cases for breeding females, plant bat-friendly gardens of wildflowers that attract the bats’ prey insects, and conduct bat walks in which citizen scientists drive and walk around urban areas with hand-held bat detectors that records bat calls and identify species through an app on their smart phones.

Students in Fulton High School’s construction class building bat houses using donated corvette circuit boards and Chevy Volt battery cases from GM. Credit: Organization for Bat Conservation.

“Most of the time, people can learn what species are living in their neighborhood in real time,” Bevan said.

Surprisingly, urban bat habitats are important, Bevan explains. Urban bat conservation may help reduce effects of WNS by providing alternative roosting habitat that might be unsuitable for the fungus that causes WNS, Pseudogymnoascus destructans, or Pd.

Urban bats likely hibernate in the city in addition to breeding there in the summer, and Pd cannot survive the temperatures and humidity found in buildings and bat houses. If the urban bat project increases public support for bats in cities, it might bolster populations that have been decimated by WNS in other habitats.

“We don’t know if big brown bats are not as affected by WNS in cities.”

Typically people find big brown bats in urban areas, a species that has escaped much of the large population drops found in other species.  “We don’t know if big brown bats are not as affected by WNS in cities,” Bevan adds.  It’s one of many questions about urban bats she hopes the citizen science project can address in the future.

The urban bat project is not just focused on big brown bats. Urban areas are important for migrating bats through urban areas from other populations in other regions. Project participants often see little brown bats in the city and northern long-eared bats in eaves of suburban homes and trees that surround them.

Bevan’s work also includes presentations with live bats from the 11 species housed at the Organization for Bat Conservation’s injured bat sanctuary. In addition to flying foxes and other bats from around the world, she gives her audiences a close-up view of species that fly around their neighborhood such as Indiana and big brown bats.

Red bat spotted in Detroit by one of Organization for Bat Conservation’s  Urban Bat Project (UBP) partners. Credit: Organization for Bat Conservation.

When a child and their parent attend one of the Organization for Bat Conservation’s environmental education events, Bevan reminds them how useful bats are in agricultural and urban areas. She cites a scientific paper (by Boyles et al. 2011) when she explains that insects can spread fungi destructive to crops and that insect-eating bats can save the agricultural industry $3.7 billion per year.

She adds that some bats like Indiana bats increase their intake of mosquitoes during the breeding period, and that supporting maternity colonies with bat boxes helps reduce numbers of the pathogen-carrying insects. All of this helps the public understand how bats benefit them and are glad to see their bat neighbors thriving.

To help the Organization for Bat Conservation in their efforts to #Savethebats, please visit their web site.

Is the coast clear for tricolored bats?

Tricolored bat with visible symptoms of WNS from Chickamauga and Chattanooga National Military Park, Georgia. Photo credit: National Park Service

This winter two scientists will set out to learn  whether tricolored bats that use winter roosts other than caves and mines are susceptible to a deadly bat disease in the coastal plains and forests of North and South Carolina — two of 38 states in the bats’ range.

In the winter of 2016, Dr. Susan Loeb of the U.S. Forest Service and Clemson University and Assistant Professor David Jachowski of Clemson did a pilot study of tricolored bats roosting under two bridges in the upper coastal plain of South Carolina. They found that some bats left the bridge for several days and returned, suggesting that they were using alternate roosts. However, because the researchers did not track bats to these roosts, where the bats were going was unknown.

Now the researchers are expanding their study to find out what alternative roosting sites tricolored bats use and if the behavior of bats and environmental conditions there can protect them from the disease white-nose syndrome (WNS).

WNS, caused by the fungus, Pseudogymnoascus destructans, or Pd, was discovered in New York State in 2007. Now confirmed in 31 states and 5 Canadian provinces, the disease has wiped out some populations of several hibernating bat species, including tricolored bats. At hibernation sites where white-nose syndrome has affected tricolored bats, average overall declines of these bats have been more than 75 percent. As observed by Loeb, these declines have been even higher at some sites in the south.

In their pilot study, Loeb and Jachowski discovered that what sets coastal plain habitats apart is a striking potential difference in temperature tricolored bats encounter at more exposed and warmer sites than at mine and cave habitats.

Temperature is critical to the spread of the WNS fungus because any body temperatures above 64 degrees Fahrenheit might mean a greater chance for the bat’s immune system to fight the fungus over the winter, Loeb said.

She said, however, that such sites might be a double-edged sword. If body temperature remains high, a bat will be less able to enter an extended state of torpor, a short form of hibernation that can last only for a few days. Possibly because of the warmer climate, the coastal plains populations of tricolored  bats might only hibernate on a daily basis to conserve energy.

If bats are able to escape WNS in these alternative habitats but remain more active due to higher outside temperatures, they must forage to survive. Finding available insects in the winter, even in the Carolinas’ warmer coastal plains, might be challenging for the beleaguered bats.

Now, with  $125,925 funding from an FWS research grant, Loeb and Jachowski plan to expand their search for the bat’s winter habitat under bridges and in trees across the coastal plains of the Carolinas. They will be joining the ranks of other FWS-funded researchers such as Dr. Jeremy White in Nebraska and State Biologist Cory Mosby in Maine who have turned their attention to small bat hibernation habitats other than caves and mines.

“The decline of tricolored bats in the southeast is concerning. When the disease first arrived in the region, researchers expected it to not be as bad because the bats could forage.  In some populations, we are seeing 90% declines.” – Susan Loeb

To measure body temperature and foraging, Loeb and Jachowski’s team will outfit temperature-sensitive radio transmitters on the bats at their winter roosts to document body temperatures and activity levels. They will use the transmitters to track bats to what might be an array of winter roosting types in this area free of caves and mines.

When the researchers capture the bats, they will swab and inspect them for the fungus and record data about the roost, such as tree height and cavity depth that might affect temperature. They will also collect fecal samples at the roost site and from the bats to determine whether the bats forage in winter.

Loeb said the study will contribute to a better understanding of bats’ susceptibility to WNS in the southeastern U.S. When the disease was first documented, researchers had hoped the region would host roosts that would be warmer than the northeastern caves and mines where the disease was first found, suggesting that the fungus would not spread to areas where wintering bats’ body temperatures would be higher than the critical 64-degree Fahrenheit threshold. In years since, however, researchers have found that even caves and mines in the southeast are cold enough to allow Pd to thrive.

“The decline of tricolored bats in the southeast is concerning,” Loeb added. “When the disease first arrived in the region, researchers expected it to not be as bad because the bats could forage.  In some populations, we are seeing 90% declines.”

Now with exploration of alternative roosts in the southeast, scientists hope some tricolored bat populations might survive if they can find warm roosts and insects to eat during lean winter months. And in the race to help bats survive WNS, hope is a good place to start.

A decade fighting a deadly bat disease

You can hear the desperation in Christina Kocer’s voice, as she describes how it felt to find bats dying from a mysterious cause in the winter of 2007. She and other scientists watched helplessly as bats in the Northeast succumbed to what would become known as white-nose syndrome, a disease that has devastated bat populations.

“Bats weren’t behaving normally. In the middle of winter, when they should have been hibernating, we were finding them flying around outside their caves,” says Kocer, white-nose syndrome coordinator for the Fish and Wildlife Service’s Northeast region. “By 2009, it looked as though all bats would be gone.”

Christina Kocer collects data on a little brown bat to aid white-nose syndrome research. Credit: USFWS

All that remains of a bat killed by white-nose syndrome. Credit: USFWS

Fortunately, ten years on, all bats are not gone. But neither is the threat. While we’ve learned a lot, biologists like Kocer continue to race the clock, looking for ways to detect, treat, and reduce the spread of the disease. The Service, along with federal, state, and private partners, has completed a national response plan for managing white-nose syndrome and is carrying it out.

You don’t need to be a scientist to be concerned. Bats are important not only from an ecological standpoint, but also from an economical one. They eat tons of insects nightly, providing a natural benefit to farmers and foresters, not to mention those who enjoy the outdoors. Some research suggests that bats could save American agriculture more than 3 billion dollars in pest control every year.

A single bat eats thousands of insects a night, offering free pest management. Credit: Ann Froschauer, USFWS

Since its discovery, white-nose syndrome has spread rapidly throughout the eastern U.S. and Canada and is now found in 31 states and five provinces. It has killed more than six million bats, with mortality rates exceeding 90 percent for many sites and species. It has been confirmed in nine species, two of which are listed under the federal Endangered Species Act as endangered and another as threatened.

We now know that white-nose syndrome is caused by a fungus — Pseudogymnoascus destructans, or Pd for short — that’s primarily spread among bats as they hibernate in caves and abandoned mines. Pd disrupts bats’ hibernation, causing them to rouse more frequently and for longer periods of time during the winter, burning up their stores of fat. Some even leave their caves and mines during the winter and early spring and become victims of hypothermia, predation, and starvation.

We’ve learned that some species, like the little brown bat, tri-colored bat, and northern long-eared bat, are more susceptible to the disease, while others show resistance.

Little brown bat infected with white-nose syndrome in Greeley Mine, Vermont. Credit: Marvin Moriarty, USFWS

Scientists today have new ways of detecting the fungus, including using ultraviolet light. Field research on treatment has begun, and work on vaccines and molecular and genetic tools to improve bat survival is underway.

Bats aren’t the only ones who hang out in caves and abandoned mines. People who enter places where bats hibernate, whether for work or recreation, can pick up the Pd fungus on their clothes, shoes, and gear, and spread it to the next site they visit. The Service and its partners have created decontamination protocols that have reduced the spread of the disease by humans.

It’s important that all cave visitors follow decontamination protocols to reduce the spread of white-nose syndrome. Credit: Wikipedia via Creative Commons

There have been some promising developments. Little brown bats have survived multiple years of infection, and some bat colonies that were nearly wiped out are gradually growing in numbers, bringing hope for recovery.

When asked about the outlook now, Kocer seems cautiously optimistic.

“There is evidence of little brown bats surviving white-nose syndrome and reproducing,” she said. “Juveniles have been born, survived, and reproduced.”

What we’re working for: healthy little brown bats. Credit: Ann Froschauer, USFWS

And while a decade may seem like a long time, Kocer notes, “Ten years is roughly the lifespan of a little brown bat, so we’ve seen only one generation since the disease was discovered.”

In that generation, we’ve learned a lot about white-nose syndrome and the importance of communication and collaboration in fighting wildlife diseases. While the situation remains dire, the knowledge and experience gained will guide the Service and its partners in the fight to stop white-nose syndrome in the next generation, and address mysterious illnesses in the future.

Visit our Bat Conservation Map to learn more about these amazing creatures.