Corky Quirk Has Always Liked the Underdog, and She Has Always Been Fascinated with Flight. For Her, Bats Fill Both of Those Niches.

Mexican free-tailed bats preparing to fly out from their roost under the Yolo Causeway.

It’s ten minutes before sundown at the Yolo Bypass in Sacramento Valley. Corky Quirk, founder of NorCal Bats, is standing at the base of the west levee with her tour group as I-80 traffic rumbles across the causeway bridge overhead. Corky flips on her bat detector. The handheld device picks up the high-frequency soundwaves of bats’ echolocation calls and lowers the pitch to be within the range of human hearing.

Corky, also known as “The Bat Lady,” has made it her mission to dispel myths and fears of bats. When people are afraid of bats, this fear can lead to devastating impacts on their populations. About half of North American bat species are at risk of severe decline, according to the North American Bat Conservation Alliance’s State of the Bats Report, published earlier this year. NorCal Bats is dedicated to the rescue, rehabilitation, and release of bats. The organization also teaches people about the stunning diversity of bats and how they benefit people and the ecosystem worldwide. Corky believes that education can be a powerful tool for creating a world where people and bats can peacefully coexist. 

The bats’ echolocation sounds became louder and more numerous as a quarter million Mexican free-tailed bats prepared to leave their daytime roosts. The crevices between the concrete structures on the bridge's underside are home to the largest urban colony in the state. The scouts emerge first and are visible, flying in low swoops between the pillars. As the minutes tick forward, more bats emerge to join the scouts until they blend into a dark cloud of bats circling in a chaotic frenzy. 

Five minutes later, the bats reach critical mass. The first group flies out together, forming a long ribbon silhouetted against the fading glow of the sky. The bats fly directly south, over the group of bystanders, before turning westward and dispersing to hunt for insects. They will hunt throughout the night before returning individually and anticlimactically. 

A group of bat watchers gathers at the Yolo Bypass west levee to view a colony of 250,000 Mexican free-tailed bats emerge at dusk to hunt for moths, mosquitos and other insects.

Satellite imagery captures their dispersal and shows how quickly they spread across the region to hunt for moths, mosquitoes, and other insects. Mexican free-tailed bats are the fastest mammals on earth, with their speeds documented at just under 100 mph. Their wings are built for speed: long and narrow. The name “free-tailed” comes from their ability to control their tail membrane freely; they can tuck it up during flight to reduce drag.

Mexican free-tailed bats are one of three species that live under the Yolo Causeway. Big brown and Yuma bats also live there, though in smaller numbers. Governor Newsom just signed a bill to make the pallid bat California’s state bat.

Bats save US farmers billions of dollars on pesticides each year. A pregnant or nursing Mexican free-tailed bat can eat her weight in insects each night, which amounts to about 50-100 moths. That’s equivalent to a 100-pound human consuming 400 quarter-pounders. There are over 1,400 species of bats worldwide, and they make up nearly a quarter of all mammal species.

Corky Quirk giving a bat talk at the Yolo Bypass Wildlife Area headquarters.

California’s largest urban colony of Mexican free-tailed bats flying out from their roost at dusk at the Yolo Causeway

GW: Was there a moment you knew you would dedicate your life to helping bats? 

CQ: What stands out is when I got to see them up close. Between seeing them in person and then seeing them under the video camera, I got to see their details and their diversity. I’ve always liked the underdog. And I’ve always been fascinated with flight. Bats filled both of those niches for me. 

GW: How did your decision to create NorCal Bats come about?

CQ: When I started working for the Yolo Basin Foundation in 2004, I was hired to teach kids about birds and wetlands. And then I started learning about the bat. If you’d asked me before that time what I thought about bats, I would have said, you know, they’re interesting, they’re part of nature. But I didn’t know a lot about them. Once I started learning about them, I was fascinated. Yolo Basin Foundation contracted a woman to do a few programs each summer with the bats. And after I met her and saw her presentation, I approached her to see if I could begin to volunteer with her and mentor under her. We did that for a couple of years. And then, in the summer of 2006, she retired, opening a niche for me. 

GW: What do bats have to teach us? What can we learn from them?

CQ: I think we could learn a lot from the bats. There are 1,462 species, so that’s a lot! I think of the Mexican free-tails. I have a soft spot for them. They get along with anybody. They don’t really care if you’re even their own species. I think that’s kind of cool. They live in massive colonies, they know each other, they know their friends, they know their family. They eat so many crop pests. They’re very beneficial to us, and often, people don’t realize how important they are to agriculture and reducing pesticide use.

GW: What memories from your bat talks stand out as most impactful?

CQ: When I’m out tabling an event at a festival, people may not realize there will be bats there. Sometimes, people come up to me and go, “Oooh! Ahh!” And then back off because they’re afraid. When I can get that person to come up and learn about and meet the bats, get them over that initial hump, and understand that they are not scary, then I find that impactful. Often, it’s the children that help me to do that. The child is interested, the child approaches the table, and then they convince their parents to come over.

GW: Have your students ever come back and told you how your bat talks affected them?

CQ: I’ve had people I’ll see years later that’ll say, you know, I’d never seen a bat in the wild until I saw your talk, and now I see them all the time! I’ve also had people talk about overcoming fears. Fear is a big problem for bats. There’s so much misinformation and a lack of understanding.

GW: You’ve mentioned it’s really important for you to help people understand bats so they aren’t afraid of them. How did you become aware of the impacts of people’s fear of bats?

CQ: I talk to people; I field a lot of phone calls from people who have bats that have moved into their attic or are living over their front door. Sometimes, people choose to kill them just because they’re afraid and they don’t understand. They don’t understand that there are ethical ways of removing them. We’ve ended up being called in by a well-meaning general public that has seen construction areas that have done very unethical behaviors. And I’m sure it’s all due to fear. 

Earlier this year, we had a relatively large rescue of a bunch of bats that were thrown away in a trash can with barbed wire and other metal debris from a construction site. The bats came from behind one of the signs on the building they were tearing down. Somebody put them in the trash can with all the rest of the debris, some of which was quite sharp. We’ve also had incidents where people will power wash them down to get rid of them. That’s all due to a lack of understanding and knowledge. 

There’s no reason to fear them. Any animal acting oddly, that individual might be sick or injured, but if you don’t handle them, you’re not putting yourself at risk. And you may even be able to help the animal. I don’t know why we’ve lost so much compassion towards other parts of the environment and nature. I’m not sure where that separation came in. 

GW: What keeps you showing up to educate the public about bats?

CQ: It’s important to me to feel like I’m making a difference, and I believe that education makes a huge difference. Every night is different. Even though what the bats do is the same, it’s always a different group of people asking different questions. The people who come for the Bat Talk and Walks with the Yolo Basin Foundation are coming to have a fun and educational evening outing. They often bring family or friends who have come in from out of town. It’s a unique experience, and they are very appreciative. 

Corky Quirk brought three species of live ambassador bats to her bat talk. She hold each one under a camera connected to a projector so the attendees each get to see the intricate details of the bats up close. She gently stretches out their wings and feeds them mealworms. The ambassador bats are rescue bats that cannot survive in the wild.

Corky Quirk leading a bat talk and walk hosted by the Yolo Basin Foundation.