Earl Nottingham | TPWD
FEELING THE HEAT
Drought, wildfires and heat waves pose challenges for a rare bird and toad.
A friendly, sunshine-faced songbird and a small toad that loves to sing loudly all night seem unaware of the threats that face their species. The actions we take to save them could save another species as well ... humans.
These two species — the golden-cheeked warbler and the Houston toad — make their homes on either side of the Balcones Escarpment, the surface expression of a fissure in the Earth’s crust formed 300 million years ago. The fault zone extends from Waco in the north to Del Rio in the south, featuring distinctive traits from both halves of the continent as verdant pancake-flat prairies converge on juniper-studded canyonlands and stratified limestone bluffs.
In addition to the millions of Texans who call it home, this region of hills and plains accommodates diverse and rare wildlife, including the warbler in the canyons to the west and the toad in the Lost Pines to the east.
Ensuring the survival of endangered species is complex and challenging work, especially with animals that require specialized habitats and live within a limited range, as is the case with the warbler and toad. With our state experiencing increased climate challenges such as droughts and wildfires, species conservation approaches are adapting by necessity, becoming ever more difficult, and ever more urgent.
To prepare for these obstacles, government agencies, municipalities and private landowners are increasingly cooperating to protect these endangered species as well as our own species.
First documented in the 1950s, the tiny Houston toad has inhabited local wetlands and woods for eons, making its presence known less by its appearance than by its high-pitched trill mating call. While the toad's physical attributes provide excellent camouflage from predators, its habitat has been overrun by an onslaught of urban and agricultural development throughout its range in the Lost Pines and post oak savanna ecosystems. Roads replaced wetlands; pastures replaced woodlands. In 1970, the Houston toad became one of the first amphibians to receive federal protections under the precursor to the Endangered Species Act.
Similar circumstances led to the 1990 endangered species classification for the warbler, the only migratory songbird to nest exclusively in the state. The “goldfinch of Texas,” as it is often called, migrates from wintering grounds in Mexico and Central America every March to landscapes in about 35 counties in the Texas Hill Country, where stands of mature oak and juniper utilized by the bird for nesting have been dramatically displaced by development.
Chase Fountain | TPWD
Maegan Lanham | TPWD
RELENTLESS, PERSEVERING CONSERVATION work over decades has helped thwart extinction for both species. But while spreading development presents one challenge, extreme climate occurrences add another. Heat waves, drought and wildfire have become more common in the last decade or so, imposing daunting dimensions to the task.
In 2011, when the state registered its driest year on record, impacts were especially profound in Central Texas. That year saw the Bastrop County Complex Fire — the most destructive wildfire in state history — consume more than 34,000 acres, destroy more than 1,600 homes and cause $325 million in property damage.
Central Texas faces a troublesome outlook: The region will get hotter and, in some years, drier, which will significantly increase drought and wildfire risk.
To deal with those trends and help species such as the Houston toad and golden-cheeked warbler, biologists are working with ecologists to estimate climate projections and identify vulnerable habitat.
Based on predictions by the South Central Climate Adaptation Science Center, the daily high temperature in Texas could rise by more than 2.6 degrees Fahrenheit by midcentury.
2022 was grim. By August, more than 98 percent of the state was in drought, with 68 percent experiencing extreme or exceptional drought conditions. By the end of October, the National Interagency Fire Center reported more than 10,300 fires had scorched nearly 660,000 acres across the state.
“These are very high numbers for Texas,” says national fire center spokesperson Carrie Bilbao. “The state ranked third in the nation for most acres burned — and first for most wildfires and human-caused fires."
FORTY MILES NORTHWEST OF AUSTIN the 27,500-acre Balcones Canyonlands National Wildlife Refuge has been central to conservation of the golden-cheeked warbler, which requires large patches of oak-juniper woodlands with mixed, dense canopy.
“Severe drought has been killing lots of trees the warbler requires,” says Michael Warriner, an Austin-based U.S. Fish and Wildlife Service biologist. “So, we’re having to adjust accordingly.”
The service is currently revising a warbler recovery plan and updating its species status assessment.
Since 2011, refuge biologists have been developing and implementing protocols on the refuge and other areas around Austin to protect people and warblers, reducing wildfire potential yet maintaining canopy cover.
Refuge guidelines have been adopted by Travis County and the City of Austin. To mitigate wildfire at the wildland-urban interface, they’ve been creating “shaded fuel breaks” at the 33,000-acre Balcones Canyonlands Preserve, one of the nation’s largest urban preserves, established in 1996 to protect habitat for eight endangered species, including the warbler. The Balcones federal refuge and Balcones city/county preserve occupy similar Hill Country habitat northwest of Austin.
“Shaded fuel breaks are common fuel mitigation methods used to protect the closed-canopy oak-juniper woodlands of Central Texas,” says Melinda Mallia, a Travis County natural resources manager. They “leave the canopy intact to shade out grasses and other fine fuels. Ladder fuels are removed to inhibit fire spread into forest canopy from higher-ignition areas, like grasslands and developments.”
Some of the protocols have been incorporated in FEMA’s Hazardous Mitigation Grant Program, which provides aid to communities for wildfire prevention and response efforts.
“FEMA has really embraced incorporating the needs of rare wildlife species into their projects where they can,” Warriner says. “In most if not all cases, there are ways to work together to protect people and species from these catastrophic events.”
FIGHTING FIRE WITH FIRE
SEEMINGLY IRONIC, ONE OF THE MOST effective methods of conserving habitat and mitigating wildfire is by means of prescribed burns. Despite a mindset favoring wildfire suppression over the past century, fire has been a naturally occurring force that serves critical ecosystem functions, from promoting new growth to removing disease to returning nutrients to the soil.
Without fire, the buildup of burnable biomass — understory fuels, increased densities of smaller trees and standing dead wood — creates conditions for catastrophic wildfires that increasingly leave wastelands in their wake.
Fighting fire with fire, so to speak, Balcones Canyonlands National Wildlife Refuge staff conduct carefully monitored prescribed burns every winter and summer.
“A lot comes down to a basic equation: how hot is the surface fire and how low is the canopy,” says refuge fire management officer Carl Schwope. “We can and do mechanically create conditions — low surface fire, high canopy base — to mitigate wildfire. But they can be labor-intensive and require debris to be removed so it doesn’t become fuel.”
On the other hand, Schwope says, “Hardwoods like oaks are vulnerable to pests; juniper is not and has significantly outcompeted hardwoods. But juniper is more fire-susceptible, so burns can help deliver a better overall tree composition for warblers.”
Earl Nottingham | TPWD
SIMILAR STRATEGIES ARE BEING DEPLOYED on the eastern side of Balcones Fault, where only a few thousand Houston toads are estimated to exist in fragmented, narrowly distributed areas. Drought and wildfire have not only set back efforts to repopulate these spots with eggs and tadpoles, they’ve all but destroyed the habitat.
The Houston toad is a habitat specialist, requiring loose, deep sands within loblolly pine forest or post oak savanna and an open understory that supports native bunch grasses and waters for breeding.
The 2011 Bastrop fire “was devastating to the people of Bastrop and the toad,” Warriner says. It burned nearly all 6,600 acres of Bastrop State Park, which “contained probably the largest Houston toad population and the largest block of contiguous pine forest habitat for the species.”
Since then, the Texas Parks and Wildlife Department and partners have planted native grasses and more than 2.5 million loblolly pines.
Prescribed burns represent an effective approach here as well, reducing underbrush and ladder fuels. Years of fire suppression have resulted in overgrowth of aggressive shrubs like yaupon holly, which produce dangerous fire conditions, reduce the diversity of insects the toad eats and may inhibit toad movement.
Lost Pines Habitat Conservation Plan administrator Cari Croft says the group has received multiple FEMA grants for wildfire work. To date, some 2,400 acres have been thinned and mulched with onsite monitoring to safeguard the Houston toad.
“The goal was to reduce heavy fuel loads outside of the burn scar to minimize the risk of another catastrophic fire, with the added benefit of improving toad habitat,” Croft says.
Earl Nottingham | TPWD
Chase Fountain | TPWD
Courtesy of AAS
From top: New growth at Bastrop State Park; the 2011 wildfire damaged most of Bastrop State Park; Elvis and Roxanne Hernandez manage their land to help the Houston toad.
LIKE SO MANY OF THEIR NEIGHBORS IN Bastrop County, Elvis and Roxanne Hernandez were deeply distraught about the devastating 2011 fire. So much so, in fact, that just months afterward, with assistance from the South Central Texas Prescribed Burn Association, they conducted their first prescribed burn.
They’re not your typical rural Central Texas landowners. He was raised outside New York City. She grew up near Chicago. They moved to the Lone Star State in 2004, buying a 53-acre former cattle ranch in McDade, population 1,285.
“We had no idea what we were doing,” Roxanne says. “All we knew was we wanted to create wildlife habitat.”
Since then, they’ve transformed their land by various means: from planting native grasses and thousands of loblolly pine seedlings to providing supplemental shelter for wildlife to conducting prescribed burns.
In fact, the Hernandez family became the first in the state in 2018 to help the Houston toad through TPWD’s permit to administer the U.S. Fish and Wildlife Service’s Safe Harbor Agreement. The initiative, which assures additional land use restrictions won’t be imposed on those who partake in conservation measures for threatened or endangered species, is an essential tool in Texas, where 95 percent of the land is privately owned. In addition, the Hernandez family has won a TPWD Lone Star Land Steward Award, and Roxanne has directed the Lost Pines Habitat Conservation Plan and is one of the founders of the Alum Creek Wildlife Management Association.
Another local landowner, the Boy Scouts of America Capitol Area Council, has been a longtime toad conservation ally. In addition to its 542-acre Lost Pines Scout Ranch, which is enrolled in the Safe Harbor program, the council manages the Griffith League Scout Ranch, a 5,000-acre stronghold for the Houston toad, half of which tragically burned in 2011.
Later in 2023, Jon Yates, the council’s CEO, expects to conduct a 500-acre prescribed burn there. Habitat, he reports, is successionally returning, and numbers, at least for now, are encouraging: “Prior to the 2011 fire, there was an average annual detection of 45 male toads onsite. This year, there’ve been 250.”
Nearby, the 302-acre Yegua Knobbs Preserve also enrolled it in the Safe Harbor program. Staff have been removing understory, mostly yaupon holly, by mulching and hand-clearing, and will conduct burns about every five years, according to Pines and Prairies Land Trust Executive Director Melanie Pavlas.
“One outcome of our work is demonstrating to traditional Texas landowners what can be accomplished — and that protecting endangered species habitat can occur alongside other land practices, including agriculture and careful development,” Pavlas says.
The Hernandez family shares this belief. And while they may seem anomalous next to many of their cattle-grazing neighbors, they’ve seen a growing number of like-minded efforts in the last decade.
As has Elizabeth Bates, a TPWD conservation specialist who oversees the Houston toad Safe Harbor program and other landowner conservation agreements.
“We’re seeing a lot more interest from landowners in managing land primarily for wildlife and ecosystem health,” she says.
There’s a lot of hope all around.
“Wildlife is an important measure of where we all stand,” Roxanne Hernandez says. “The collaborative work taking place here is the type of approach other regions might consider in mitigating climate change — and restoring a degree of ecological balance that will make them more resilient.”
Houston Toad Presence Increased
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