The first results of a biodiversity study at the Wuest Ranch — home to Natural Bridge Caverns — are in, and environmental experts say they highlight the need for Hill Country habitat protections.

The yearlong effort by the Wuest family and Blackland Environmental identified 10 species of frogs and nine species of bats living on the land surrounding Natural Bridge Caverns, showcasing how important it is to protect Hill Country habitats, as they support a wide variety of species, said Jeremiah McKinney, wildlife biologist and operating manager of Blackland Environmental.

“To find this diverse number of species just a few minutes’ drive from the urban areas of San Antonio is remarkable,” he said.

Frog species in the area included the cliff chirping frog, Cope’s gray tree frog and the spotted chorus frog, and bat species discovered there include the big brown bat, Seminole bat and Mexican free-tailed bat.

McKinney said he and his team decided to survey first for anurans — amphibian species including frogs, toads and tree frogs — on the property because they are great “indicator species.” Indicator species are those whose presence, absence or abundance can be evaluated to assess the quality or condition of the surrounding habitat.

The number of anuran species found on the Wuest Ranch indicates a thriving biodiversity on the property, said Brad Wuest, president and CEO of Natural Bridge Caverns. He noted about 20 local anuran species are found in Comal and Bexar counties, so finding 10 on their ranch shows it is abundantly biodiverse.

Wuest added that he hopes the survey results will inspire other landowners in the area to protect their properties’ habitats.

“To my family, it’s super important that we be good stewards of the resource we have the privilege to manage — that being the caverns and our ranch above the caverns,” he said. “We hope there are land owners that see what we’re doing and that creates a spark in them and they think, ‘That’s cool. I wonder what species I have on my property and what can I do to better care for this land that I have.'”

Comal and Bexar are two of the fastest-growing counties in the nation. Bexar County ranked eighth in numeric growth between July 2022 and July 2023, adding almost 30,000 people, while Comal County ranked seventh in percentage growth over that same period, at 5%, according to U.S. Census Bureau data released last month.

It’s becoming increasingly important to understand the ecology in these counties, McKinney said — and to learn how to prevent the loss of species as growth occurs.

“What it shows is that …. there’s quite a bit of biodiversity in the Hill Country … that could be lost by being developed, because people don’t even always understand what all they have on their land,” he said. “I think a lot of property out there has quite a bit of biodiversity that folks may not even know it’s there, and might even change their mind about what they want to do with it if they knew that.”

The biodiversity surveys, which so far have focused on finding out how many species of frogs and bats call the Wuest Ranch home, came about as a result of a friendship that formed between the ranch owners, brothers Brad and Travis Wuest, and McKinney through their children, who compete in competitive shooting.

The inspiration for the above-ground surveys came from work that the Wuests had been helping do below the surface, Brad Wuest explained. The previous year, the Wuests had partnered with Zara Environmental to do underground biological surveys, which resulted in the discovery of six different species.

“We were telling [McKinney] about the cave biological inventory work we were doing on cave-adapted species and he was fascinated and asked if we had done similar studies on the surface of our ranch,” he said. The brothers quickly were on board with McKinney’s idea, Brad Wuest said.

The 2,600-acre ranch has been in the Wuest family since 1884. Cibolo Creek splits the ranch across two counties. Its west bank lies in Comal County, where the caverns and the majority of the ranch are located. On the creek’s east bank is Bexar County, which encompasses 430 acres of the property.

In 1960, four St. Mary’s University students — Orion Knox Jr., Preston Knodell, Al Brandt, and Joe Cantu — got permission from the Wuest brothers’ grandparents and began exploring the caves on the ranch. This changed the Wuest family’s destiny forever. On their fourth expedition, the young men discovered the entrance into what is today Natural Bridge Caverns — the largest known cavern system in Texas.

Today the caverns are a public attraction, visited by hundreds of thousands of people every year. The Wuest brothers continue to explore the caverns’ numerous winding passages and make new discoveries.

Above ground, McKinney and his team have logged more than 2,292 man-hours in the past year recording and analyzing audio data, making multiple nighttime trips into Cibolo Creek and catch-and-release trapping, McKinney noted.

“I think the whole idea is what we do with the information we learn,” he said. “So what can we educate people about? Can we do better at the ranch? How can the Wuests manage it even better? So step one is just getting the information; next is what to do with it.”

The study is ongoing, with McKinney and his team now turning their attention to snakes, small mammals and birds, he said.

“We recently caught a Central Texas whip snake — I was super excited,” he said. “I’ve never caught one before, so I’m kind of a nerd in that regard.”

Lindsey Carnett covers the environment, science and utilities for the San Antonio Report. A native San Antonian, she graduated from Texas A&M University in 2016 with a degree in telecommunication media...