NEWS: Two lightning-caused wildfires on the same site in eastern New Mexico yielded profoundly different results. Why? Prescribed fire played a key role.
Two lightning-caused wildfires on the same site in eastern New Mexico yielded profoundly different results. Why? Prescribed fire played a key role.
On June 10, 2009, lightning sparked a fire in remote grasslands some 30 miles east of Roswell, New Mexico. Strong winds whipped the flames, stoking a plume-dominated wildfire—the term for fire so hot it creates its own weather and wild, unpredictable winds. By the time firefighters fully contained the Cato Fire three days later, more than 55,000 acres—86 square miles—had burned.
Fast forward eight years to July 2017. Lightning again ignited a wildfire in the same area as the 2009 fire. But this one, called the East Cato Fire, burned just 372 acres before dying out for lack of fuel. Why the profoundly different outcomes from two lightning-caused wildfires in the same location? Prescribed fire played a critical role.
About two-thirds of the acreage that burned in the 2009 wildfire lies within the boundaries of Sand Ranch, a 58,600-acre federally owned parcel 35 miles east of Roswell. It’s managed by the Bureau of Land Management (BLM) as habitat for the lesser prairie-chicken, an imperiled species of prairie grouse that inhabits the southern Great Plains.
Sand Ranch encompasses a big swath of potential lesser prairie-chicken habitat, but there’s a whole lot more to good habitat than sheer acreage. Like many other grassland birds, prairie-chickens need diverse grassland structure—a mosaic of grassland patches with varied structure that meets their particular needs throughout the year.
Historically, a closely entwined duo of natural forces—fire and fire-influenced grazing by bison and other large herbivores—created that essential patchwork of grassland habitat. Decades of fire suppression and altered grazing patterns shifted that dynamic, reducing both the structural and species diversity of prairie grasslands.
Because of this, the BLM made careful plans to reintroduce fire to Sand Ranch through prescribed burning. It wasn’t a decision lightly made. While low-intensity fire can help create the vegetation mosaic lesser prairie-chickens need, an uncontrolled, high-intensity fire can destroy nesting habitat, plus a whole lot more. This is dry country and aversion to fire runs deep.
Local rancher Kyle Dillard voiced a common fear as he recalls a wildfire that came on the heels of the intense drought of 2011-12. “My place caught on fire—we burned 5,000 acres from lightning—and it blew for three years. It was a disaster.”
“We had another fire in June [2016] that we started accidentally with our tractor,” Dillard continued. “But it rained right after, and it actually looked really good. If you could predict the rainfall, then fire might be OK.”
That’s just what prescribed burn planning aims to do—to identify site conditions that can produce a contained fire that meets the landowner’s range management objectives, and to time the burn treatments to meet those conditions.
On Sand Ranch, the overarching range management objective is to maintain optimal lesser prairie-chicken habitat, which means creating a dynamic mosaic of vegetation. Nathan Curnutt, BLM fire management specialist, was tasked with developing and implementing the prescribed burn plan for Sand Ranch.
According to Curnutt, the plan divides Sand Ranch into 15 burn units that can be burned on a rotation schedule. Prescribed fires are carried out prior to prairie-chicken nesting so that birds are not impacted. The goal is to remove about 50 percent of the vegetation within the burn area, creating the vegetative mosaic that lesser prairie-chickens and other grassland wildlife need.
The long planning process came to fruition in 2016, when the BLM’s fire crew carried out the first-ever prescribed burn on Sand Ranch, treating a total of 3,100 acres in two areas. The burns were picture-perfect. Fire snaked through the prairie, leaving behind areas that didn’t burn and areas that did.
Dr. Scott Carleton of New Mexico State University studies lesser prairie-chickens on Sand Ranch and was ecstatic about the burns. “Lesser prairie-chickens were seen out foraging in [the burned area] right after the burn. Within two weeks we had a lek move from an adjoining unburned area to the recently burned area,” he said.
In late February of 2017, the BLM fire crew burned two more areas totaling 10,700 acres. Then in July, the East Cato Fire started, right in the middle of the Sand Ranch, where the huge Cato Fire had burned in 2009. After scorching 372 acres, the East Cato wildfire ran into the grasslands that had burned four months earlier. Starved of fuel, the fire was easily extinguished.
The difference in both economic and ecological costs of wildfire versus prescribed fire are dramatic. The 55,000-acre Cato Fire cost approximately $525,000 to suppress, and it incinerated all grassland habitat in its path. The BLM’s 2017 prescribed fires cost about $40,000, created optimal wildlife habitat, and reduced fuel loads.
That’s why prescribed fire is a core conservation strategy within the Natural Resources Conservation Service’s Lesser Prairie-Chicken Initiative (LPCI). LPCI offers technical and financial support to farmers and ranchers interested in carrying out voluntary conservation measures that improve their rangelands for lesser prairie-chickens.
Only five percent of the lesser prairie-chicken’s habitat occurs on public land parcels like Sand Ranch, so engaging private agricultural producers in habitat conservation is essential to the bird’s survival.
The beauty of LPCI’s conservation effort is that what’s good for lesser prairie-chickens is also good for livestock. The healthy habitat that lesser prairie-chickens need is also resilient, productive, drought-resistant forage for livestock—win-win conservation at its best.
LPCI focuses conservation dollars on sites and strategies where efforts are likely to do the most good for lesser prairie-chickens. In terms of both economics and ecological results, prescribed fire is a remarkably effective tool in the conservation toolbox.
Though prescribed burning is not yet an integral part of the ranching culture in eastern New Mexico, the East Cato wildfire offers an encouraging vision of its potential for both recovering grassland habitat and reducing fuel loads in this arid region.
The Lesser Prairie-Chicken Initiative, led by the USDA’s Natural Resources Conservation Service, is a partnership-based, science-driven effort that uses voluntary incentives to proactively conserve America’s western rangelands, wildlife, and rural way of life.