Documentary on the fight against a bat-killing plague flies into Austin

Director Kristin Tièche says the seed for her new documentary, The Invisible Mammal, was planted back in 1999, when she was a film student in upstate New York.

“I was sitting at this pub on campus, and I looked up and the sky was just filled with bats,” said Tieche, a native Californian who had never seen a bat before.

“I just thought it was the coolest thing ever,” she said.

These days, such a sight is all but impossible to behold in New York and many other states. A deadly disease called white-nose syndrome is to blame.

The Invisible Mammal follows a team of researchers as they set out to protect bats from the disease, which has emptied entire caves and roosting spots once teaming with life. It’s being screened Tuesday night at AFS Cinema and will be followed by a Q&A.

White-nose syndrome is caused by an invasive fungus found in Europe, likely brought to America on the clothes of a visitor who came to see American bats up close. It kills by starving hibernating bats.

The disease causes bats to “wake up too often during winter and they burn up their fat reserves and die before spring,” said Winifred Frick, chief scientist at Bat Conservation International.

First detected in New York state in 2006, the disease steadily spread across the continent, inflicting catastrophic damage on bat colonies in the Northeast, mid-Atlantic and Midwest. In some parts of the U.S. and Canada, white-nose has wiped out over 90% of bat populations. While the disease exists in Texas, it has not proved as destructive so far.

When it appeared in California in 2019, Tièche thought back to that night decades before when she saw her first bat flight.

“I knew at that moment that it was time to launch this film project,” she said.

The result is a nonnarrated documentary that follows researchers and conservationists across the country, as they protect bats and study ways to battle white-nose syndrome.

Its primary focus is Frick and the team of scientists behind the Fat Bat Project, an initiative started in Michigan’s Upper Peninsula that aims to keep bats well fed around their winter hibernation.

“The idea was could we help bats get fat in the fall and also help them recover their body condition in the spring?” Frick said. “Because we had research that showed that the bats that were surviving tended to be fatter at the start of hibernation.”

Tièche said it was not until she arrived in Michigan to shoot that she realized the team of scientists working on the Fat Bat Project was comprised entirely of women.

“I knew at that point that I also was going to tell the story of women in science,” she said.

White-nose exists in Texas, but the colonies of Mexican free-tailed bats so celebrated in the Hill Country are at lower risk of death. That’s largely because they do not hibernate in the same way some other species do, and insect meals are available in Central Texas deeper into the winter months.

Still, Austin’s Congress Avenue bat bridge makes an appearance in the documentary. The film also opens and closes with immersive scenes — filmed by Austin wildlife cinematographer Skip Hobbie — of bats flying out of the Bracken Cave Preserve, home to the world’s largest bat colony.

Courtesy of Kristin Tièchei

“I told him [Hobbie] I was hoping for people to fall in love with bats when they watch,” Tièche said. “You protect what you love.”

White-nose syndrome continues to decimate bats as it spreads, but there’s reason for cautious optimism. Some species that were nearly wiped out in the Northeastern states are beginning to show modest recovery, Frick said, though it is not fully clear why.

She said the Fat Bat Project, which has expanded across the Northeast and into Texas, is also showing promise as one tool of many that could stave off total population collapse in some areas.

The Invisible Mammal is screening at 6:30 p.m., Tuesday, July 14, at AFS Cinema. It will be followed by a Q&A with filmmaker Kristin Tièche, producer Matthew Podolsky, cinematographer Skip Hobbie and Winifred Frick of Bat Conservation International.