Oklahomans Work To Boost Horned Lizard Population
by Heide Brandes
“Iremember playing with those all the time as a kid. They seemed to be everywhere, but now you don’t see them that much anymore,” my brother said when I asked him if he remembered Texas horned lizards, aka “horny toads.” Growing up in Moore, we saw them in the culverts and sandy areas around our elementary school, those fierce-looking but laid-back creatures that could notoriously shoot blood out of their eyes to deter predators.
Once found across 80 percent of Oklahoma counties, these toadlike lizards (yes, they are lizards) are harder and harder to spot. Because they prefer native grasslands as hunting grounds for their favorite ant snack and loose soil to burrow into when the temperatures get extreme, the decline in natural habitat is a primary culprit for their population decline. As more of Oklahoma’s land is used for crops or converted into nonnative grasses, the numbers of Texas horned lizards are getting lower and lower.
Although horned lizards are not on the state or federal threatened or endangered lists, their population numbers are of concern. In Oklahoma, several entities are working together to help bring the population back up.
Where Did They Go?
Historically found across much of the western two-thirds of Oklahoma, the Texas horned lizard still thrives in the remaining
open, native habitat. Based on surveys and reports from the public by the Oklahoma Department of Wildlife Conservation, this lizard is now thought to be locally common and widespread in the western third of the state, said Jena Donnell, the department’s communication and education specialist.
The conversion of native ranges to nonnative pastures and crop fields is the leading cause of decline, not just for the Texas horned lizard but for other species as well. “Habitat loss has been an issue for lizards for about a century, but the decline became more evident in the 1960s,” Donnell said.
“While Texas horned lizards face multiple challenges, maintaining enough quality native habitat may be the biggest. These lizards need large, intact prairies to thrive. Keeping lizards in quality habitat is easier than returning the species to a restored area.”
The most substantial decline in lizard numbers is in central and eastern Oklahoma, Donnell said. These hearty creatures have managed to persist in little pockets, namely in central Oklahoma.
Photo courtesy of the Oklahoma City Zoo.
Good News and Good Work
Not all news regarding the spiky future of the Texas horned lizard is bad. One of the first efforts to protect the species was to create a closed season that makes it illegal for people to catch, possess, or harvest the lizards. The restriction has been in place since 1992, and it’s illegal to keep a horned lizard as a pet.
The Wildlife Department manages hundreds of thousands of acres of public lands that benefit lizards and other wildlife. Department biologists also conduct wildlife surveys and collect sightings from the public to monitor the status of the species. “The Wildlife Department has also partnered with several universities and organizations, including the University of Oklahoma, Sam Noble Oklahoma Museum of Natural History, the Oklahoma City Zoo, and Oklahoma State University, to learn more about these lizards and where they occur,” said Donnell. “The natural-resource team at Tinker Air Force Base has also been a dedicated lizard-conservation partner.”
Blake Bower, senior animal caretaker of reptiles and amphibians at the Oklahoma City Zoo, organized the zoo side of the field tracking program at Tinker Air Force
Base. He said the population of horned lizards has dropped because the habitat has become so fragmented. In addition, the ant populations that the lizards feed on have declined because of pesticide use and the growing number of invasive fire ants that outcompete the native ant species.
But the zoo has a plan.
“For the last several years, we’ve been doing a head start program where we collect eggs or newly hatched babies from Tinker, and we bring them to a lab on the zoo grounds,” Bower said. “We raise them for a year or two, and then we release them.”
When a hatchling horned lizard is born, it weighs less than a gram. Many are killed because of predation from other animals. “So we raise them here, and when they are half or almost full grown, we release them. When they are bigger, they have a much better chance of survival,” Bower said.
Photo by Wade Free, Oklahoma Department of Wildlife Conservation.
How To Help
For lizard lovers and conservation enthusiasts, the easiest way to help the Texas
horned lizard is to maintain quality places for them to live and simply share the word about them. Planting native bunch grasses and flowering plants helps the lizards move around more easily and attracts their favorite food — ants.
“Harvester ants are feeding on the seeds of these grasses and forbs, and while people may avoid spraying ant mounds with insecticide, they may not realize that spraying ‘weeds’ with herbicide can be just as detrimental to the lizards and their food supply,” according to the Wildlife Department. Replacing Bermuda grass and other invasive, sod-forming grass can also help Texas horned lizards.
“We’re all about conservation here at the zoo, and the horned lizard is an animal that is kind of a good symbol of Oklahoma,” said Bower. “You mention horned lizards, and everyone always says they used to see them all the time when they were younger. They’re also a good indicator species of how the ecosystem around them is doing.”
The public can report lizard sightings at https://www.wildlifedepartment.com/
wildlife/report-wildlife-sighting/texas-horned-lizard/form.
