By Charles Scudder, The Dallas Morning News
MASON, Texas (AP) — A dozen conservationists clad in khaki and forest green march into the Hill Country brush.
The Dallas Morning News reports noontime sun hasn’t broken through the clouds. The prickly pears are full of ripe purple fruit. Late summer rain has kept the grasses green and red dirt damp. Conditions are ideal for this rescue mission as the procession moves wordlessly onward.
In their hands are cameras and clear deli cups, the kind used to take home leftover potato salad. Inside each are tiny lizards, about the size of a quarter and only a few weeks old.
They are the latest, greatest hope for bringing their species back from the brink.
Call them horny toads, horned frogs, Phrynosoma cornutum or the Texas horned lizard, the state reptile is in dire straits. For several decades, they’ve been vanishing from Texas landscapes for reasons researchers cannot fully explain.
Now, Texas zoos, Texas Parks & Wildlife Department officials, Texas Christian University biologists and more are working together to release hundreds of horned lizard hatchlings here, on state land about 100 miles west of Austin.
The horned lizard procession arrives in a clearing surrounded by granite hills at Mason Mountain Wildlife Management Area. There’s open dirt, a few tufts of low grass, tall brush nearby, lots of termites and a few varieties of ants. Perfect horned lizard habitat.
Jim Gallagher, a wildlife biologist with Parks & Wildlife, spreads his arms wide.
“Ground zero,” he says. “Who’s got how many?”
“I’ve got 15,” says Jaimie Peltier, a zookeeper at the Fort Worth Zoo.
She kneels and pries the lid off one of the cups.
Carefully, she lifts each baby lizard and sets it on the ground. Some scurry away quickly, others hunker down and hardly move at all. Peltier’s face turns red as Diane Barber, her boss, pulls out a phone to take photos of the zookeeper.
“I’m trying not to cry,” she says, grinning.
Peltier has worked with the horned lizards for months to prepare for this day. She helped pair lizards for breeding, scooped droppings, refilled ant feeders, checked for nests, watched, waited, weighed and measured them week after week, packed the hatchlings into these cups and brought them here.
It’s emotional, she says, to finally see them scamper out of sight.
In a booming bass, Gallagher sings as the little lizards look for ants to snack on.
“Born free, free as the wind blows .”
The horned lizard hatchlings at Mason Mountain are on their own now. But before they got here, these critters were the product of the careful, calculated work of biologists, ecologists, researchers, landowners and zookeepers across the state.
It’s an uphill battle, one that has become more and more common as species like the Texas horned lizard struggle to survive.
The horned lizard is not on the brink of extinction — yet. It is listed as “threatened” in the state, but strong populations in New Mexico and elsewhere keep it off the federal endangered species list.
Status as a state treasure helps give the lizard cultural protection, but it could easily become just another Texas legend.
“There’s a lot against us in terms of establishing these guys,” Barber said in the spring. She’s the Fort Worth Zoo’s curator of ectotherms, in charge of the cold-blooded creatures there. “There’s a lot of species where people wait until the 11th hour and there’s 20 left — literally, only 20 — and people come to us. It’s far better to try to take action.”
To lose the horned lizard would be to lose something uniquely Texan, and it’s why so many people are working to bring them back.
“It’s more like a bald eagle or something,” said Dean Williams, a TCU biology professor who has worked with the lizards for a decade. “It’s symbolic of the West.”
On fall Saturdays, just across campus from Williams’ biology lab, TCU fans dressed in purple and white fill Amon G. Carter Stadium. Just before kickoff, a gray mascot with a cartoonish head runs onto the field.
The mascot — here, it’s a “horned frog” — leads the stadium in a chant of “Go! Frogs!” After every touchdown, the stadium echoes with refrains of “Horned Frogs, we’re all for you,” but few TCU students have seen the real thing outside of zoos.
The lizards’ round, flat bodies and namesake horns make them look prehistoric. Their unique defense mechanism — shooting blood from their eyes at canine predators —only adds to their reputation as Texas tough.
The Comanche people believed that horned lizards would always run in the direction of bison, and used them to guide hunts. Other American Indian cultures saw them as symbols of strength. Cowboy stories told of horny toads that could live a century or more.
One tall tale from Eastland, Texas, tells of a lizard that survived 30 years sealed in the cornerstone of the county courthouse without food or water. As the story goes, the lizard went on to appear onstage in Dallas and meet President Calvin Coolidge in Washington, D.C. When it died a few months later, its body was embalmed and put on display at the courthouse. Tourists still stop to snap photos of “Old Rip” the horny toad.
They were once so populous, the lizards were backyard favorites across the state. Slow and docile, they were easy to catch and made for fun summertime pets. Some Texans remember keeping the lizards in a shoebox under the bed. Others remember carrying pillowcases full of lizards to trade at Boy Scout jamborees.
Then, slowly and inexplicably, they started to vanish.
Fire ants, the insidious South American invaders that destroy lawns and pack painful venomous bites, are the most oft-cited perpetrators. They’ve decimated populations of harvester ants, the primary diet of the Texas horned lizard. They also destroy lizard nests and eat hatchlings.
Human interference shoulders some of the blame as well. Urban sprawl and the spread of pesticides certainly harmed the horned lizard’s prospects.
By the time researchers noticed the horned lizard was disappearing, it was almost too late. Now, you’re unlikely to find a single lizard in the wild east of the Interstate 35 corridor. You’re more likely to find them in South and far West Texas.
About 10 years ago, TCU’s Williams joined an effort with Parks & Wildlife and Texas zoos to study and protect the horned lizard.
Barber’s team at the Fort Worth Zoo pioneered breeding strategies, learning how to successfully raise the lizards in captivity. Others like the Dallas Zoo have joined the effort.
“We’re all sort of working together for the common good,” said Nathan Rains, a wildlife diversity biologist with Parks & Wildlife.
Early attempts, such as raising lizards to adulthood before release or moving wild-caught lizards from one area to another, were found to be too costly or impractical.
Last year, Parks & Wildlife released hatchlings — just a few weeks old — in an attempt to establish a stable population. Sixty-three babies from the Fort Worth Zoo were released at Mason Mountain, a trial run. It’s unclear if any of those have survived, since they were too small to carry radio monitors commonly used on adult lizards.
At the end of last year, Parks & Wildlife and the zoos settled on a new goal: 300 hatchlings for release by September 2018. That number, they guessed, would give the lizards a greater chance to reach adulthood, breed and produce their own wild offspring.
“Nobody’s more optimistic than I am,” Rains said, “but we don’t know if it’s going to work yet.”
Far from the pink flamingos wading near the Fort Worth Zoo’s entrance, past the saltwater crocodile floating lazily alongside his big glass window, behind the air-conditioned building where Mexican long-nosed bats dart back and forth in a darkened room, a small building away from public access serves as headquarters for the horned lizard breeding program.
The lizards spend their winters inside a walk-in refrigerator. Keepers raise the temperature to simulate the arrival of spring in late March.
At 66 degrees, it’s time for a wake-up call.
A sleepy lizard cracks open an eye as a large hand pulls her out of the sand and brushes granules from her face.
“When they come out covered in sand like this,” says Peltier, the zookeeper, “it’s adorable.”
The lizard, No. 207121 according to a spreadsheet to Peltier’s right, has three dots of nail polish on her back: Green-Green-Black. Each individual is identified by its six-digit number and the unique nail polish pattern the zookeepers apply every time the lizards shed their skin.
Peltier places Green-Green-Black onto a small scale. Thirty-five grams, the same as when she went into hibernation back in November. As Peltier marks down the measurement, Robyn Doege, supervisor of aquatics, carries the lizard to a small tank with other females.
Each lizard’s DNA has been tested by Williams at TCU. Those DNA results go into a computer program that analyzes every individual for its best possible mating match.
The goal: Pair the male and female lizards to create the most genetically diverse offspring possible. Weed out the related lizards, try to pair wild-caught critters with individuals born in the zoo.
“It’s like Tinder for horned lizards,” Doege said.
Within a few weeks of waking from hibernation, the lizards at the Fort Worth Zoo are clearly ready for action. They’ve been in bachelor and bachelorette tanks, warming up and starting to move.
First up, a young male and two older females. One of those females has been at the zoo since 2011, and was once selected as a model for TCU’s billboards and promotional materials.
“He gets two girlfriends this year,” Doege says, placing the three lizards in a sandy outdoor enclosure.
After exploring the enclosure’s boundaries, the male spies the TCU model.
He bobs his head up and down in quick succession. “Hey, girl.”
No response.
He scrambles a little closer, then stops short. He bobs his head again. “What’s up?”
Still, no response. He bobs again. “Wanna get out of here?”
Finally, she bobs back. His cue. The male scrambles over, leaps on her back and grabs one of her namesake horns with his strong jaws.
Longer horns are appealing to male lizards, as it gives them something to hold onto during the act. The female bucks and spins, flips upside down and rolls as soon as the male jumps on her back. “Is he too small for her?” Peltier asks.
“We’re giving him a shot,” Doege says.
Just like online dating, sometimes the most compatible match on paper isn’t the best practical pair. A female in San Antonio might be the best match for a male in Fort Worth. In those circumstances, it’s up to Barber and Vicky Poole, the species studbook keeper, to evaluate the matches and make adjustments.
“We have so many animals and so many possibilities,” Poole says. “Every year we have to go through this. It’s the dating game.”
While the young male courts the TCU model, Doege introduces other pairs. Green-Green-Black, the sleepy lizard who woke from hibernation covered in sand, is paired with Yellow-Yellow-Black, a male who has fathered 15 hatchlings at the zoo. They mate right away.
It’ll be at least a month before there are any signs of eggs, and even then every nest may not be viable. Three hundred hatchlings is still the goal.
“If each of them lay 20 eggs,” Doege says after the lizards are all paired with their potential mates, “we have a shot.”
Zoos were once treated like exotic sideshows, places to view strange beasts from around the globe. Think of tigers in steel cages, elephants tethered with large chains.
In the late 20th century, however, there was a push among zoos to concentrate more on animal husbandry and welfare, Barber says. They became arks, places to collect and care for as many species as possible, especially as their natural habitats were in decline.
But zoos can only fit so many animals. Conservationists can support a finite number of projects at one time.
Consequently, the mind-set among many zoos has changed. They must engage in wild conservation as much as they collect animals and protect them in captivity. Zookeepers also work to make the environment better to protect those species.
“We’re not just amassing animals to keep them in captivity forever,” Barber said.
One of her first such projects at Omaha’s Henry Doorly Zoo in the early 1990s was to capture what were believed to be the only Wyoming toads in existence, a last-ditch effort that classified the species as “extinct-in-the-wild.”
In Omaha, she helped produce tadpoles for release near Laramie, Wyoming, and supervised the toad’s studbook, part of the Association of Zoos & Aquariums’ species survival plan.
Barber still keeps a photo of the first adult Wyoming toad she spotted in the wild, long after they had been declared extinct. It was very likely an individual she had released as a tadpole years earlier.
“My love for toads started then,” she said.
Today, the horned lizards are just one of her focuses. She regularly travels to Puerto Rico, where she’s helping to reintroduce the Puerto Rican crested toad. In the same room where the horned lizards are breeding, she’s overseeing an operation to support populations of rare Louisiana pine snakes and spot-tailed earless lizards.
She says there’s no playbook for this kind of work. As our planet changes and more species are shoved toward extinction, humans are learning how best to protect and reintroduce them to the wild on a case-by-case basis.
But not all toads are created equal.
One species may benefit from widespread support and research, while another might not succeed due to human conflicts over procedure and best practices.
That chatter can slow, and sometimes even halt, the effort to bring a species back.
To that extent, the Texas horned lizard is lucky.
Texas landowners flood Parks & Wildlife with calls asking to reintroduce the lizard on their land. TCU’s support with genetic research has helped diversify captive populations.
Still, everyone who’s had a hand in this project knows it will be nearly impossible to bring the lizards back to their original range.
In one of the earliest efforts to reintroduce hatchlings, half were killed by fire ants within 24 hours of release. This summer, a Parks & Wildlife project that released tagged lizards 75 miles southeast of Abilene ended early. No lizards were left to track by late August.
Even in good conditions, a high mortality rate among Texas horned lizards makes it all the more important to release hundreds of hatchlings at once.
“These projects are not things that may be successful at first,” Barber said. “Sometimes you get caught up and think, is this even going to happen in my lifetime?”
For weeks after pairing day, Peltier and Doege watch the sandy enclosures at the zoo. They look for signs that the females have laid eggs, weighing them regularly.
On May 17, Green-Green-Black weighed 40.7 grams. A week later, she was down to 26.6 grams. She was the first to dig a nest.
Peltier and Doege transfer her 24 eggs to a clear deli cup with a thin layer of vermiculite gravel. Each clutch is placed inside an incubator behind the zoo’s mountains and deserts building, where you’ll see the horned lizards on display.
By late June, the zookeepers have found 135 eggs, and the tiny lizards begin hatching in late July.
Each is hardly the size of a penny as they slowly climb out of the paper-thin eggs over several days. Peltier measures them in millimeters as Doege assigns each a six-digit code of their own.
Green-Green-Black’s offspring don’t get nail polish dots right away, however. Most are headed to the wild, where the colorful dots would counteract their camouflage.
In the first week of September, it’s time to pack up the baby lizards.
Peltier and Doege count the hatchlings and label each container with a piece of neon green painter’s FrogTape.
Twenty-one of Green-Green-Black’s offspring are headed to Mason Mountain. In all, they pack 93 baby lizards in a Styrofoam box cushioned by newspaper.
That’s far under the goal of 300.
Next year, they’ll have more juveniles at breeding age. More potential parents means more potential offspring. The bar is still set at 300 hatchlings for release in 2019.
On a cool and cloudy Wednesday morning, Doege and Peltier drive the lizards to Mason and carry the deli cups into the brush. They take turns placing the hatchlings carefully on the ground. Doege kneels and scoops Green-Green-Black’s offspring out of the deli cup two or three at a time.
And that’s it.
Unceremoniously, they walk back out of the brush, leaving the little lizards behind.
“Enjoy the horned lizards,” Doege says to the Parks & Wildlife biologists. “We’ll make more next year.”
There’s just one experiment left, one that will give Parks & Wildlife a better idea if these lizards survive more than just a few days.
Ten lizards were held from the initial release group to be part of a new tracking test. Technology originally developed to find skiers after avalanches has been adapted for tracking small reptiles.
A few hours after the other lizards were released, Rains and Barber glue tiny trackers onto the hatchlings before releasing them in a clearing not far away. The antennas hang off their backs like extra-long tails, bobbing behind as they dart toward a patch of prickly pear.
The next morning, Rains returns to the clearing. He watches the ground with each step, keeping an eye out for any hatchlings underfoot.
He opens a big yellow and gray receiver, turning up the monitor to check for any sign of the lizards.
Almost immediately, the device emits a rapid beep-beep-beep-beep out of the static.
In the Hill Country brush, the horned lizard hatchlings are still there.
Information from: The Dallas Morning News, http://www.dallasnews.com
