A huge swath of Far West Texas has been formally designated as a “dark sky reserve,” a recognition of the long-running work of astronomers, conservationists and local communities to protect the region’s nighttime skies from light pollution.
The Greater Big Bend International Dark Sky Reserve was certified on Thursday by the International Dark-Sky Association, an Arizona-based non-profit that oversees such efforts across the world.
“Astronomers, dark sky enthusiasts, and local residents are all aware of just how magnificent and pristine the skies over this region are,” said Teznie Pugh, Superintendent of the University of Texas at Austin’s McDonald Observatory. “This designation gives us a way of sharing what we all already know with the world.”
The observatory and other entities like the Nature Conservancy had pushed for the creation of the reserve for more than a year, arguing that the designation would protect astronomers’ research while also supporting tourism in the area.
While the designation itself is mostly symbolic - the group that approved the reserve doesn’t have any kind of regulatory power - the steps that were taken for the Big Bend region to qualify in the first place could have a tangible impact on dark sky preservation.
Notably, the reserve designation guidelines called for local governments across the Big Bend region to adopt stricter outdoor lighting rules.
Over the past year or so, local city councils and county commissioners voted to update their existing lighting ordinances, often at the urging of McDonald Observatory staffers like Bill Wren, a longtime dark skies advocate who retired from the observatory in February.
According to the observatory, four counties and five municipalities within the new reserve boundaries updated their existing rules with “relevant language to ensure their lighting reflects best practices.”
“It has been a true community effort, and the people of the area should be proud of what we have all achieved together,” said Pugh.
The dark sky reserve’s boundaries stretch across Jeff Davis, Brewster and Presidio counties and extend into parts of northern Mexico. The McDonald Observatory and the Nature Conservancy’s Davis Mountains Preserve make up a “core” area of the reserve with the strictest outdoor lighting rules already in place. A number of popular public parks are located within the reserve boundaries, including Big Bend National National Park, Big Bend Ranch State Park and the Black Gap Wildlife Management Area.
Ashley Wilson, a conservationist who reviews reserve proposals for the International Dark-Sky Association, described the new Big Bend reserve as historic.
“It is the largest protected dark sky place in the world,” she said in an interview.
Wilson said the Big Bend region’s years-long efforts to prevent light pollution stood out to her as she reviewed the application for the new reserve. Usually, she said, her organization works with communities where the idea of dark skies as a resource is a relatively new idea.
“But here, especially with McDonald Observatory as one of the core partners, they have been leading efforts here for decades,” she said. “It’s building up instead of starting from scratch.”
While the reserve designation paves the way for continued dark sky preservation efforts - like retrofitting old lighting fixtures with more “dark sky friendly” options - an open question remains as to how or whether the region’s local governments will seek to actually enforce their updated lighting rules.
Many communities struggle with that follow-through, Wilson acknowledged.
“They get the certification, they get through their town councils, but most communities only have maybe one, maybe a small team of enforcers,” she said. “So now you have a very limited team of people trying to educate and talk to an entire community.”
In a statement, Big Bend National Park praised the news of the reserve being dedicated.
“People who know and love Big Bend National Park should be both delighted with, and proud of this designation,” said Bob Krumenaker, the park’s superintendent.
