Pesticides used to treat exotic game at the “Texafari” hunting Star S Ranch near Mason, Texas, drifted over to the Eckert James River Bat Cave. Credit: Monika Maeckle / San Antonio Report

The Eckert James River Bat Cave, a wildlife preserve run by the Nature Conservancy of Texas, missed its usual mid-May opening date because the conservation organization and its neighbor, the Star S Ranch, are working to formalize an agreement under which the exotic game ranch would cease spraying pesticides that drift onto the preserve.

“It’s taking longer than we hoped,” said Nature Conservancy spokeswoman Vanessa Martin, adding that the conservancy had secured assurances from Star S Ranch owner William Scott to stop using pesticides around the cave, which is home to 1.6 million Mexican free-tailed bats and their offspring each summer.

“We’re working towards an agreement to have everything we asked for – no longer using pesticides around the cave, no longer allowing pesticides to drift. Above and beyond that, we’ve asked for a legally binding, permanent solution to provide an additional buffer, an easement around the cave.”

Scott confirmed the ranch’s commitment to stop using pesticides around the bat cave. “Having said that, we are not willing to surrender any of our property rights in the process,” he said via email. Scott cited myriad investments his ranch has made that have facilitated visitor access to the bat cave.

“We built the fence around the cave to secure the area after trespassing was detected. We repaired the access road from the County Road to the cave at our expense twice after heavy rains. We provided equipment to support National Geographic magazine when they did an article on the bat cave some years ago, and we have maintained the county road through our ranch and across the river, particularly after flooding,” he said.

In June 2018, more than 25 people who were gathered at the preserve to observe the nightly emergence of millions of Mexican free-tailed bats, saw Permethrin pesticides from aerosol sprayers drift across the fence line shared with the preserve. Scott’s ranch staff applied the chemical to its animals. The incident sparked an investigation and $1,200 in fines by the Texas Department of Agriculture for using a pesticide “in a manner inconsistent with its label.”

The pesticide drift incident, combined with the appearance of a drone hovering above the nightly emergence a few weeks later, caused the Nature Conservancy to close the cave to the public two months early last summer. It has remained closed ever since.

Typically, the cave is open to the public on weekends from mid-May through September. Residents of the nearby Hill Country community of Mason and tourists from around the state look forward to witnessing the nightly “bat-nado,” a whirlwind that occurs when the bats emerge en masse from the cave each night to feed.

The maternal colony almost doubles in size as the summer progresses and makes for a unique natural spectacle. Female bats arrive pregnant from Mexico in March and typically give birth in late June. After five or six weeks of nursing, baby bats join their mothers in nightly outings to consume two-thirds their body weight in insects each evening. The wildlife destination is listed on the Mason Chamber of Commerce webpage as one of the top “outdoor adventures” in the area.

The Mason community is eager for the bat cave to reopen. Tony Plutino, the proprietor of Llano River Region Adventures, a kayaking and guiding operation, took issue with a post the Star S Ranch shared on Facebook on May 24. The photo showed an axis buck dead in the foreground as a father and son leaned over its back, smiling.

“School is out,” said the caption. “What are you doing with your kids?? Axis rut is coming. Come visit us soon!”

Plutino wrote in response: “We were going to take ours to the Eckert James River Bat Cave, one of the most amazing natural spectacles in the world and adjacent to your property. But it seems that your outfit is refusing to coordinate your animal pesticide treatments with opening hours at the Bat Cave Mason Tx.”

Plutino then shared the post on the Mason County TX online community page and encouraged its 3,000-plus members to reach out to the media and neighbors to express their concerns.

Star S Ranch owner William Scott agreed with Plutino that the cave is an amazing natural spectacle. When asked if he ever had visited the cave, he wrote: “… We often send guests and our grandchildren go as well. We look forward to it being reopened.”

Scott, Mason residents, businesses, and bat-watching fans will continue to wait.

Martin mentioned another snag in reopening the cave: Longtime bat cave steward Vicki Ritter will not be returning this year “for personal reasons.”

Known as “bat granny” by the Mason community, Ritter for years regaled crowds with her folksy, educational presentations of the bats’ life cycle.

Martin said the Nature Conservancy of Texas is continuing to explore staffing solutions and Nature Conservancy staff could fill in until the bat cave steward position is filled. 

“We’re still very committed to opening the cave this season and providing this experience to people, we just have to ensure the agreements we are seeking are in place and that we can provide a safe and enchanting experience for visitors,” Martin said. “We’re as invested in this as is the community. We just need their patience.”

San Antonio Report co-founder Monika Maeckle writes about pollinators, native plants, and the ecosystems that sustain them at the Texas Butterfly Ranch website. She is also the founder and director of...