It was 9:15 p.m. on the Wuest Ranch when the first small chorus of frogs began to make their chirping calls.
The sun had just fully set, turning the Texas sky a deep navy tinged with the darkest purple. Few stars poked through the moonless, blackening sky, but Mars was clear and bright overhead.
Coming from the tall grasses on Cibolo Creek’s banks, three distinct songs rang out — a quick low trill that sounded like a cricket, a deep broad honk almost like a dog’s bark, and a rich croak that was distinctly froglike.
Wildlife biologist Jeremiah McKinney leads a small group through the creek’s waters, nabbing frogs with a quick swipe of his hand as soon as he heard their calls. After catching the slippery amphibians, he would show them to the group, pointing out specific characteristics of each.
The aim is to learn more about what species live on the ranch, McKinney explained, so he’s surveying the different kinds of wildlife there to assess its biodiversity. What he finds could provide further insight into how the Hill Country is being affected by encroaching development.
Cibolo Creek splits the Wuest Ranch, home to Natural Bridge Caverns, across two counties just north of San Antonio. Its west bank lies in Comal County, where the caverns and the majority of the ranch is located. On the creek’s east bank is Bexar County, which encompasses 430 acres of the 2,600-acre property.
As sprawl moves closer to where the ranch and caverns are located, McKinney, chief operating officer of Blackland Environmental LLC, hopes these surveys will be the first of many on the Wuest property, which belongs to brothers Travis and Brad Wuest, who own and run Natural Bridge Caverns.
Comal and Bexar are two of the fastest-growing counties in the nation; Bexar County ranked ninth in numeric growth between July 2021 and July 2022, adding almost 30,000 people, while Comal County ranked ninth on the list of counties in percentage growth, according to U.S. Census Bureau data released earlier this year.
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.
“Not only is this work important for [the Wuests’] understanding [of their ranch], but it’s also important for their neighbors and local companies that want to cooperate with landowners here,” he said. “It will take folks working together, thinking about benefiting species here … really taking a holistic approach to benefit the area.”
A history of exploration
McKinney and his family live just 5 miles from the Wuest Ranch. He recalls meeting Travis Wuest first several years ago through their kids, who compete in competitive shooting.
Not long after, McKinney met Brad Wuest, and the two became fast friends due to their mutual love for outdoor activities.
It was McKinney’s idea to launch a ranch-wide comprehensive biodiversity assessment of the ranch, and his friend liked the plan.
The ranch has been in the Wuest family since 1884. Brad Wuest said he wanted to better understand the immense property left to him and his brother, which not only is the home of the Natural Bridge attractions but still operates as an active cattle ranch and houses the two brothers’ homes.
“We want to be good stewards of this land, and that means understanding what’s here,” Wuest told the San Antonio Report. “This area is known for its pristine aquifers, but what we’re all still learning about today is how important the relationship is between what’s above the surface and what’s below it.”
In 1960, four St. Mary’s University students — Orion Knox Jr., Preston Knodell, Al Brandt, and Joe Cantu — acquired 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 visitors every year. The Wuest brothers continue to actively explore the caverns’ numerous winding passages and make new discoveries.
From surface to underground
It’s not just below the ground that remains unexplored, McKinney said. With roughly 95% of land in Texas privately owned, wildlife species in Texas are “likely vastly undercounted,” he said.
“People don’t often want to let biologists or others on their land because they want people to stay away from their property, so a lot of our estimates are probably way off,” McKinney added.
He shared an anecdote about an endangered species of cactus he and his team recently found on a private property in East Texas five counties away from where it is known to grow. He and his team were then able to trace the cactus’ spread across the five other counties, showing the area had more biodiversity than was previously known.
As the Hill Country continues to develop and grow, animals will need places like the Wuest Ranch to thrive, McKinney explained.
The squeeze Hill Country animals are experiencing is called habitat compression, said James Rice, a Texas Parks and Wildlife biologist and the superintendent of the Albert and Bessie Kronkosky State Natural Area, located just northwest of San Antonio.
“The critters that live in that land — they die, they migrate, or they adjust,” Rice said. “That causes the compression. I want to make it really clear, it’s not good or bad — Mother Nature has no conscience. We know people are coming into Texas and we’re creating homes for them. That’s the situation. What’s the reaction? Well, that’s where we [biologists and land stewards] come in — is managing these reactions.”
While currently counting and documenting the frogs and snakes on the property, McKinney is also using new technology, an ultrasonic recorder that can be paired with software to detect bats by their unique sound patterns, to collect data. He’s installed six around the Wuest Ranch, which is directly next door to the Bracken Cave Preserve, home of the world’s largest known single bat colony comprising 6 million to 10 million bats. However, McKinney suspects there are likely other species of bats that call the Wuest Ranch home, something he and others hope to learn about.
“We used to have to set up nets and try to catch the bats so we could document what species were present on a property,” McKinney said. “But that was difficult for a number of reasons. Biologists would have to be careful not to get bitten and it was also potentially bad for the bats. Plus, we missed a lot of bats if they simply flew over or under the net.”
While McKinney is performing the ranch’s first full biological assessment above the ground, Natural Bridge Caverns launched its first underground biological survey last year. During the survey, conducted by Texas-based Zara Environmental, an unmapped stream of water hidden deep below the surface was discovered. The group also identified six species previously unknown to live in the caverns, including a groundwater crustacean called a Stygobromus russelli, which looks like a small shrimp without eyes.
Natural Bridge Caverns plans to showcase these new species, as well as others previously found in the cavern system, in a new educational exhibit scheduled to open in early 2024, Prosapio said. The exhibit will also likely include the new data from McKinney’s initial surveys about which species live above ground, she added.
“This assessment is really setting a baseline,” McKinney said, adding that he is looking forward to doing future surveys on the ranch and seeing how the area’s growth is affecting the species of the area.
