KHOU 11 reported at the time that a combination of inclement weather and light pollution resulted in the birds’ demise. But the terrible event ultimately helped to spur on a new campaign: Lights Out Texas.
Nighttime is when most birds migrate, said Taylor Keys, the program manager at Texan by Nature, which leads the statewide effort in conjunction with other organizations. The "Lights Out" campaign asks Texans to turn out inessential lights between 11 p.m. and 6 a.m. during the spring and fall migration periods.
“Birds that are migrating at night use the stars to get their bearings and migrate through the night skies,” Keys said. “There’s a lot of light emitting from cities, not only from businesses but from homes and whatnot, so that light can disorient birds while they’re using the stars to migrate.”
Although the migratory birds’ critical peak migration period lasts from Sept. 5 to Oct. 29, the full migration period for the fall extends until Nov. 30.
Last month, Dallas Mayor Eric Johnson said in a tweet he'd issued a proclamation to encourage residents to shut off extraneous lights. In it, he notes that nearly 2 billion birds fly through Texas every spring and fall, representing up to a third of all birds that migrate throughout the country.
In one study of 125 American cities, Dallas ranked third in its light pollution exposure to migratory birds. At the same time, Dallas has been designated as one of Texas’ seven “Bird City” communities.
Dallas’ lights have claimed their fair share of birds, spanning 73 species over the past year, according to D Magazine. Last fall, 457 bird deaths were reported downtown. But in the spring, as 23 buildings agreed to go dark, the number dropped to 233 deaths.
Light pollution threatens birds migrating, especially in large metro areas. To raise awareness, I’ve proclaimed Sept. 27-Oct. 17 as #LightsOutNights in Dallas, and I am joining @laurawbush in encouraging residents to turn off non-essential lights. #LightsOutDallas #LightsOutTexas pic.twitter.com/NeErq5gp9o— Mayor Eric Johnson (@Johnson4Dallas) September 24, 2021
Each year across the United States, up to one billion birds are killed after crashing into windows and walls, according to the Texas Conservation Alliance, which has helped to lead the campaign in Dallas-Fort Worth, along with the Dallas Zoo and Perot Museum.
Since 1970, bird populations in the U.S. have decreased considerably, losing one out of every four birds, according to the website BirdCast. In addition to buoying the earth’s ecology, bird watching is big in the Lone Star State. Nature tourism in the Rio Grande Valley injects $300 million into the economy annually.
"[Birds] don’t have forecasts like we do." – Jim Bednarz, senior lecturer at the University of North Texas
The research into how light pollution affects migratory birds is in its infancy, said Jim Bednarz, a senior lecturer in the biological sciences department at the University of North Texas. Still, anecdotal evidence points to the fact that bird carcasses seem to accumulate around large buildings.
Over the span of millions of years, birds evolved to travel at night because the atmosphere tends to be more stable, and they can avoid “predator pressure," he said. Birds are attracted to light, and artificial ones turned on at night are confusing to the creatures because they’re a novel feature, evolutionarily speaking.
Like with the Galveston bird collision, poor weather conditions can cause birds to change course, he said. They use the stars to navigate, so cloud-cover and rainstorms may cause them to drop in altitude.
“They don’t have forecasts like we do,” Bednarz said.
Birds also provide a tremendous ecological service in insect control, he said. If bird, lizard, turtle and bat populations continue to decline, it will result in pest issues.
In addition, Keys said some birds can act as pollinators.
Texans who want to help their safe migration can look into complying with the campaign year-round, she said. They can aim their lights down and use motion sensors and warmer lights. Those who own buildings and homes can also learn how to make their glass more bird-friendly.
It’s also in humans’ self-interest to protect their winged friends, Bednarz added: “[Birds are] important as far as their variety of functions in the ecosystem, which we also depend on for our survival.”