Why are bats a Halloween staple? Why is their silhouette, slapped onto a cheap decoration, synonymous with fright? Why are they the one thing Bruce Wayne dreads?
Maybe it’s because we fear what we don’t understand and there’s a lot we don’t understand about bats.
“They aren’t scary,” said Abby Tobin, a bat biologist and white-nose syndrome coordinator with the Washington Department of Fish and Wildlife. “They are so misunderstood.”
Tobin said she was drawn to bats in large part because they’ve been understudied. She said the idea of researching mysterious species, and helping answer some unanswered questions about their biology and ecology, excited her.
In general, the species biologists know best are the easiest ones to study. That, in part, explains why so much about bat behavior remains unknown.
“They’re a really hard animal to study,” Tobin said. “They’re small and they’re cryptic; they’re out in the middle of the night.”
Biologists don’t know much about bats in general, but Evergreen State bats are especially mysterious, Tobin said. Part of the work she’s doing now is focused on answering some straightforward Washington bat questions, such as, “Where are they?”
“We don’t have a ton of data to specifically point to where in Washington,” she said. “We’re slowly trying to piece that together.”
Much of Tobin’s work is focused on white-nose syndrome, a disease that’s killing millions of bats and one of the greatest threats North American bats face.
White-nose syndrome appears to have shown up in American bats in 2006. It’s caused by a fungus that does well in cold, damp environments. Many bat species hibernate in cold, damp caves, so they’re hanging out in precisely the places white-nose fungus thrives.
The fungus gets in through bats’ bare skin, often on their faces. It’s called white-nose syndrome because infected bats look like their faces are covered in a white mold.
Bats’ immune systems are suppressed when they’re hibernating. They aren’t awake, so they can’t groom themselves and clean off the fungus. Once white-nose gets a foothold it can start messing up the bats’ physiological balances. It can wake them up, which forces them to burn precious energy, weakening them.
Many of the bats infected with white-nose syndrome die of dehydration or starvation. The disease can also invade their wing tissues, causing tears.
At the moment, white-nose syndrome is wreaking havoc mostly on eastern American bats. In some species, the disease can wipe out 90% of a colony.
In 2016, biologists found white-nose syndrome in Washington for the first time. It was unexpected, Tobin said, because the disease hadn’t previously been found west of Oklahoma.
For now, white-nose syndrome doesn’t seem to be as devastating for western bats, and Tobin said that may be because western bats behave differently.
Back east, many bats hibernate in massive underground colonies. Washington bats don’t convene in caves as much, Tobin said.
“They’re probably more dispersed on the landscape; using lots of different kinds of roosts,” Tobin said, noting that Washington bats are more likely to spend their winters in rock crevices, for instance.
It’s also possible that Washington’s hibernating bats wake up more frequently during the winter, Tobin said. Waking up more often might mean Washington bats groom themselves more frequently and keep the white-nose fungus at bay.
“We’re still trying to fully understand, ‘Is the spread going to be slower?’ ” Tobin said.
Tobin said she thinks it’s generally irrational to fear bats. Just leave them alone, she said. If you have to move one, just don’t touch it directly.
It’s true that most human rabies cases in America come from bats. But an incredibly small percentage of bats have rabies – some estimates say about 0.1% – and only one to three Americans die of rabies every year. For comparison, about 30 Americans die every year after being struck by lightning.
Tobin said that when she talks to someone with chiroptophobia – a fear of bats – she tries to explain the animals’ biology. She said she tries to paint them in a positive light and help people understand their vital role in Pacific Northwest ecosystems.
Bats are incredibly beneficial, Tobin said. They eat enormous quantities of insects, including mosquitoes. If the nocturnal aerial hunters were to go away it could hurt the Inland Northwest’s forestry and agricultural industries, Tobin said.
“I feel they should be respected,” she said. “People should realize that they have an important role in our ecosystem.”