White-Nose Syndrome
Anyone who’s walked past the Manistique School & Public Library in recent summers has likely been greeted with an arresting sight: bats. Dozens of them, midsleep in the shaded terrace by the library’s front entrance, gray little lumps that almost seem to be growing out of the building’s brick walls as they huddle together through the daylight hours. In the summers since the Schoolcraft Conservation District relocated its offices across from the library, this has been the welcoming party to herald District Manager Ashley Reitter into work each morning.
“It’s always so fun to see them there,” Reitter said. “Even though bats aren’t everyone’s cup of tea, they’re really incredible, complex animals. We’re lucky to live in an area where you can just see them out and about.”
Bats are undeniably remarkable creatures. Their order includes the smallest mammals in the world, and yet they’re so diverse they comprise 25% of all mammalian species. They can live to be over 30 years old, making them some of the oldest living animals in the Great Lakes region. As if in deference to their place in the insatiable vampire mythos, bats are also voracious eaters, capable of gulping down 1,200 mosquitos in a single hour and their entire body weight in insects every night; estimates have put the value of their pest control services in the US at anywhere from 3.7 to 53 billion dollars annually.
Most importantly, they play a crucial role in our ecosystems, acting as pollinators, seed dispersers, fertilizers, and a food source all in one.
It’s understandable then that biologists became alarmed when, in the winter of 2006, bats across New York State began dropping dead.
At first, the decimation was limited to only a handful of caves. The cave divers who submerged into their depths would find entire colonies littered across the cold ground, belly-up and lifeless, the only hint of their demise a mysterious white fungus speckling their snouts. As it turned out, this fungus was a symptom of an emerging disease that has gone on to eradicate millions of bats in subsequent years.
White-nose syndrome (WNS), named for the white fungus that develops on the snouts and bodies of infected bats, is a fungal disease that disrupts bats’ hibernation patterns, causing them to wake up more frequently during winter. Their instinct to search for food upon waking drives them from their roost and out into the frigid cold. If an infected bat doesn’t die of exposure, it will eventually die of starvation as its fat reserves are depleted and no food source presents itself. In the 17 years since WNS’ discovery in New York, the disease has spread to eight Canadian provinces and at least 33 states. Michigan, which saw its first confirmed case in 2014, is among these.
According to Michigan’s most recent Wildlife Action Plan, the Little Brown Bat, one of the most common bat species in the United States, has seen an 80-98% population decline across various Northeast and Midwest states in the past five years, and the species may be extinct in these regions as early as 2026. The Northern Long-eared Bat, another common Michigan species, has undergone a similar 98% decline. Some species have been hit harder by WNS than others, but, especially with the ongoing habitat loss and climate change crises, its overall impact has been devastating to state populations.
“There were a few bats around the library entrance for a couple weeks in August, but not nearly to the degree that there has been in the past,” Reitter said. “This could be due to any number of factors, but it’s certainly worrying when you take the broader context of WNS into consideration. We’re not just talking about a COVID-level pandemic. We’re talking about an extinction-level threat.”
While the damage of WNS can’t be undone, there are signs of hope on the horizon as researchers learn more about the disease and implement strategies to mitigate it, including artificially increasing the temperature of winter roosts and using UV light exposure to damage the WNS pathogen. Individuals are encouraged to avoid handling bats and practicing gear and clothing decontamination when going on cave or mine diving expeditions. Homeowners can help provide much-needed habitat and food sources by building a bat house or establishing a bat-friendly garden.
The SCD’s upcoming events include a habitats workshop on October 25, scrap tire recycling drive on October 27 and 28, and a family-friendly Halloween lamplit walk on October 30. Details for these and more can be found on schoolcraftcd.org. These events wouldn’t be possible without the generosity of the community; thank you for your support in our education initiatives.
“It’s always so fun to see them there,” Reitter said. “Even though bats aren’t everyone’s cup of tea, they’re really incredible, complex animals. We’re lucky to live in an area where you can just see them out and about.”
Bats are undeniably remarkable creatures. Their order includes the smallest mammals in the world, and yet they’re so diverse they comprise 25% of all mammalian species. They can live to be over 30 years old, making them some of the oldest living animals in the Great Lakes region. As if in deference to their place in the insatiable vampire mythos, bats are also voracious eaters, capable of gulping down 1,200 mosquitos in a single hour and their entire body weight in insects every night; estimates have put the value of their pest control services in the US at anywhere from 3.7 to 53 billion dollars annually.
Most importantly, they play a crucial role in our ecosystems, acting as pollinators, seed dispersers, fertilizers, and a food source all in one.
It’s understandable then that biologists became alarmed when, in the winter of 2006, bats across New York State began dropping dead.
At first, the decimation was limited to only a handful of caves. The cave divers who submerged into their depths would find entire colonies littered across the cold ground, belly-up and lifeless, the only hint of their demise a mysterious white fungus speckling their snouts. As it turned out, this fungus was a symptom of an emerging disease that has gone on to eradicate millions of bats in subsequent years.
White-nose syndrome (WNS), named for the white fungus that develops on the snouts and bodies of infected bats, is a fungal disease that disrupts bats’ hibernation patterns, causing them to wake up more frequently during winter. Their instinct to search for food upon waking drives them from their roost and out into the frigid cold. If an infected bat doesn’t die of exposure, it will eventually die of starvation as its fat reserves are depleted and no food source presents itself. In the 17 years since WNS’ discovery in New York, the disease has spread to eight Canadian provinces and at least 33 states. Michigan, which saw its first confirmed case in 2014, is among these.
According to Michigan’s most recent Wildlife Action Plan, the Little Brown Bat, one of the most common bat species in the United States, has seen an 80-98% population decline across various Northeast and Midwest states in the past five years, and the species may be extinct in these regions as early as 2026. The Northern Long-eared Bat, another common Michigan species, has undergone a similar 98% decline. Some species have been hit harder by WNS than others, but, especially with the ongoing habitat loss and climate change crises, its overall impact has been devastating to state populations.
“There were a few bats around the library entrance for a couple weeks in August, but not nearly to the degree that there has been in the past,” Reitter said. “This could be due to any number of factors, but it’s certainly worrying when you take the broader context of WNS into consideration. We’re not just talking about a COVID-level pandemic. We’re talking about an extinction-level threat.”
While the damage of WNS can’t be undone, there are signs of hope on the horizon as researchers learn more about the disease and implement strategies to mitigate it, including artificially increasing the temperature of winter roosts and using UV light exposure to damage the WNS pathogen. Individuals are encouraged to avoid handling bats and practicing gear and clothing decontamination when going on cave or mine diving expeditions. Homeowners can help provide much-needed habitat and food sources by building a bat house or establishing a bat-friendly garden.
The SCD’s upcoming events include a habitats workshop on October 25, scrap tire recycling drive on October 27 and 28, and a family-friendly Halloween lamplit walk on October 30. Details for these and more can be found on schoolcraftcd.org. These events wouldn’t be possible without the generosity of the community; thank you for your support in our education initiatives.
First published in the Pioneer Tribune October 19, 2023