6 U.S. Sites to See Bats in Action

Happy International Bat Week!

By Austin Price

October 24, 2018


Photo courtesy of Tamir Kalifa/Austin American-Statesman via AP

When bat biologist and photographer Merlin Tuttle created Bat Conservation International in 1982, he found himself professionally defending his favorite underdog mammal. As he recounted in BCI’s printed magazine, “Even conservationists looked at me like, ‘Sure, next you’ll try to sell us on the virtues of rattlesnakes and cockroaches.’”

Tuttle, who retired from a leadership role at BCI in 2009, is currently active as founder and executive director of Merlin Tuttle's Bat Conservation. Over the last 35 years, he and fellow bat conservationists have dedicated their careers to protecting the nearly 1,300 species of bats worldwide from human disturbance and misperception. Bats serve a special ecological role, the biologists behind BCI say. They control pests, pollinate a variety of plants, and provide guano, a rich fertilizer. Without bats, many of our tropical and desert ecosystems would collapse, not to mention our global supply of tequila.

Scientific importance aside, bats are frankly cool animals, boasting unique, almost folkloric qualities. During much of the year, these stealthy, nocturnal fliers punctuate sunset vistas with their stunning emergence—come dusk, bats swarm from their roosts in fluttering ribbons to track their insect prey with distinctly tonal clicks and squeaks. As Ben Cosgrove wrote in Time, “Bats represent a melding of the practical and the poetic so rare as to be almost unique in the nonhuman mammalian world.”

Catching sight of a sunset bat emergence should be on everyone’s wildlife-viewing list, particularly as many species fluctuate in number due to habitat disturbance and a disease called white-nose syndrome. The good news is, bats can still be found nearly everywhere. And there’s a good chance you may even live near a place where they hibernate, roost, hunt, and pollinate. Here are a few particularly notable spots across the U.S. to see bats in action.

Congress Avenue Bridge, Austin, Texas

Constructed in 1980, the Ann W. Richards Congress Avenue Bridge connects South Austin with the heart of downtown north of the Texas capital’s Lady Bird Lake. Thanks to its many crevices, which create an attractive place to roost, the bridge is also home to the world’s largest urban bat colony. When bats first started moving into this man-made home, Austinites petitioned to have the colony eradicated. But Tuttle, who moved to Austin in 1986, argued otherwise and fought for bats’ right to roost.

Since then, the city has come to appreciate its 1.5 million insect-eating, swarming neighbors. In fact, the bat has become somewhat of an unofficial mascot of the city (where the motto, after all, is “Keep Austin Weird”), and the bridge annually draws more than 100,000 wildlife viewers to witness the bats emerge into the Texas summer-sunset sky. Any evening between May and October is a good time to post up on the bridge and look out for the soaring colony. 

Bracken Cave Preserve, near San Antonio, Texas

While Austin hosts the world’s largest urban bat colony, the largest colony overall is but a stone’s throw away, 20 miles northeast of downtown San Antonio in the Bracken Cave Preserve. Here, 15 million Mexican free-tailed bats roost each summer, producing millions of young each year before the bulk of the colony hibernates or flies south to winter in Mexico.

Since the cave is privately owned and operated by Tuttle’s Bat Conservation International, Bracken Cave visitors must be paying, reservation-making members. So although a trip to Bracken requires a little more planning, bat-loving pilgrims will find one of most stunning displays of bat emergence in the world.

Millie Mine, near Iron Mountain, Michigan

Near the border between Wisconsin and Michigan’s Upper Peninsula, the Millie Mine bat-viewing site represents one of 30 sites across the U.P. where visitors can see bats emerge from their roosts within abandoned iron ore mine shafts. The opening to the shaft is inconspicuous—just a hole in the grass along a forested trail on Iron Mountain, beneath which a mine shaft drops 360 feet into the earth, providing a home for multiple bat species. A grate covering the entrance allows resident bats to come and go.

While thousands of mine shafts have been sealed to reduce hazards, the Millie Mine offers a roost for mating bats in the summer and a place to hibernate in the winter. Bat viewers can gather on an observation deck uphill from the mine, which offers a view of the majestic exodus that occurs each evening during summer and fall.

Carlsbad Caverns, New Mexico

As the story goes, a teenager named Jim White was rounding up stray cattle in the northern foothills of the Guadalupe Mountains around the turn of the 19th century when he saw bats swarming out of the ground like a plume of smoke. Upon further investigation, he discovered a hole in the ground, from which bats continued to emerge for hours. “Any hole in the ground which could house such a gigantic army of bats must be a whale of a big cave,” he later wrote, recounting the tale of how he discovered Carlsbad Caverns.

Today, visitors to Carlsbad Caverns National Park can experience the same bat emergence that sparked White’s curiosity. Seventeen bat species live in the park. From May through October, the park’s amphitheater offers a sunset view of the bats as they corkscrew in a dense cloud into the desert night.

Nickajack Cave, near Chattanooga, Tennessee

Nickajack Cave tells a rich history. Carved out of the side of a bluff overlooking the Tennessee River, the cave once gave refuge to the area’s Cherokee tribe members as well as river travelers passing through. During the Civil War, both Union and Confederate armies mined it for saltpeter to make gunpowder. Then, in 1967, the Nickajack Dam partially flooded the cave. Today, Nickajack Cave is home to a colony of gray bats that fly over the reservoir in search of insects each night during summer and fall.

The cave is gated to protect the roost from human disturbance, which has historically led to the decline of this particular bat species. But visitors can still see the bats emerge over the still, blue reservoir from a viewing platform above the cave, or from a canoe or kayak—watercrafts can offer an insect’s-eye view of the flying mammal on her evening hunt.

Yolo Basin, near Davis, California

Mexican free-tailed bats can be found throughout California, save for the High Sierra and parts of the north coastal region. But the Yolo Bypass Wildlife Area hosts the state’s largest colony of this species. Like Austin’s Congress Avenue Bridge, the Yolo Causeway, which bisects the northern section of the preserve, provides an artificial roost for the opportunistic species.

Bats aren’t the only wildlife drawn to the Yolo Basin. Hunters and bird-watchers come for the many species of waterfowl, raptors, shorebirds, and migratory birds. But through guided tours and private events, the state-managed wildlife area offers the chance to see bats shoot from their roosts to hunt for insects over the nearby rice fields and wetlands of California’s Central Valley. 

This article has been updated since publication.