During National Pollinator Week, it’s important to celebrate all of our pollinators — including bats. If you’ve ever enjoyed a refreshing margarita, thank a bat. The blue agave plant, from which Tequila is derived, depends on bats as pollinators. Because bats are valuable, but often misunderstood, I thought I’d republish my bat article that originally ran in The Denver Post in 2005.
When Merlin Tuttle was growing up in Tennessee he made a remarkable discovery. The gray bats that resided in a nearby cave were migratory. His observations contradicted everything he had read about the bats.
“I got my parents to take me to the Smithsonian, where I politely informed leading authorities that I had found gray bats that seemed to migrate,” he recalled. “They were impressed with my observations, gave me several thousand bat bands and suggested I band them to see where they were going.”
Tuttle banded over 40,000 bats and traced their migratory movements from northern Florida to northeastern Tennessee and from northern Alabama to Missouri. He used the migration data to write his doctoral thesis.
The data also showed that gray bats were headed for extinction. “The species was declining alarmingly which led to my conservation efforts and the founding of Bat Conservation International.” Today the gray bat population is well on its way to recovery.
The conservation group has worked for 20 years to educate the public about bats. To review, all bats aren’t rabid, bats won’t attack humans, bats can’t get tangled in hair, they aren’t blind, and they aren’t flying rodents.
In spite of the positive public relations, most people still shudder at the thought of a bat encounter. Would it help to know baby bats are called pups?
“They are cute as any puppy,” Tuttle said. “They are among the most gentle animals on earth, but people don’t understand them.”
Bats play a vital role in our environment and our economy. They disperse seeds, pollinate crops, and feast on insects. The world wouldn’t be as healthy if we didn’t have bats, according to Tuttle.
Bats consume tons of insects nightly—one brown bat can eat over 1000 mosquito-sized insects each hour. Economically speaking, bats provide a valuable service to farmers by eating agricultural pests like the corn earworm and armyworm moths.
And, if you’ve ever enjoyed a refreshing margarita, thank a bat. The blue agave plant, from which Tequila is derived, depends on bats as pollinators. “Seventy percent of all tropical fruits are reliant on bats for pollination or seed dispersal,” Tuttle said. The list includes bananas, plantain, figs, dates, avocados, mangos, papaya and guava.
“Gardeners may be surprised to learn that bats not only eat a lot of insects, they also scare the dickens out of them. Many of the worst pests listen for bat echolocation and flee when they hear bats.”
Bat Conservation International is based in Austin, the summer home to a massive bat colony. Austin always had bats under the Congress Avenue Bridge, but when the bridge was reengineered in 1980, crevices underneath made for a perfect bat roost.
The Texas capital now hosts the largest urban bat colony in North America. Over 1.5 million Mexican free-tailed bats migrate there each year.
“Health officials predicted problems,” Tuttle said. “But we’re still waiting for the first human bat attack.”
For those who are still afraid of bats, Tuttle said, “Less than two people die of rabies from a bat each year. But healthy dogs kill about 20 people a year and domestic violence takes about 10,000 people a year. So if you’re brave enough to own a dog or get married, you shouldn’t be afraid of bats.”
The Congress Avenue Bridge bats are now the top tourist attraction in Austin, bringing in $8 million dollars annually. Visitors gather each evening to watch the bats emerge from under the bridge for their nightly insect hunt.
David Hinojosa is an Austin native who remembers when the bat flight was just a family affair. “We’d have a picnic and wait for dusk to arrive. It’s a spectacular sight of Mother Nature.”
Now, as an account executive for a software company, he takes visiting clients to the bridge to share the experience. “It starts with just a few bats and then there are sheets of bats that fly off in the same direction. It’s like a never-ending stream of bats.”
Colorado’s Bat Colony
Colorado is home to its own bat colony, according to Rick Adams, professor of biology at the University of Northern Colorado and president of the Colorado Bat Society. The Orient Mine, located in Saguache County, is the summer residence of a large colony of Mexican free-tailed bats.
“What’s unique about this bat colony is that it’s almost all male. It’s a huge bachelor roost,” Adams says. Estimates range from 150,000 to 250,000 bats. Each summer, hikers navigate the trail to watch the out flight. The Orient Land Trust, a nonprofit preservation organization, protects the area.
“Bats are shrouded in mystery,” Adams says. “Very little is known about them even though they’ve been studied for years.
“They live on the extreme edge of mammalness. They are the only true flying mammal and their heart beats 20 beats a second when they’re flying.”
Bats are the most gregarious of all mammals. “They are very social and are passionate parents when it comes to child care,” Adams says. “They’re different than people expect.”
Most bat and human encounters happen in a stressful situation, like when a bat is caught in a house. “People are running around screaming and the bat is flying around and screaming. The bat just wants to get out,” Adams explains.
The Colorado Bat Society is a nonprofit group that promotes bat education and research. Society members developed a bat trunk for the University of Colorado Museum’s Science Outreach Program. Teachers can order the trunk and use its contents—books, tapes, a mounted bat, and a bat skeleton to educate students about bats.
Another program uses trained volunteers to monitor bat roost sites in Boulder County.
There are 18 species of bats that live in Colorado, although a new species may have been found in north Boulder last year, according to Adams. Colorado bats aren’t pollinators, but they do have voracious insect appetites.
Education efforts appear to be working. Instead of calls for how to exterminate bats found in home attics, Adams says he now gets calls asking how to safely relocate them.