Rare tortoises may have been hit hard by fires
ST. GEORGE - Now that an army of firefighters is gaining the upper hand on a slew of southwest Utah wildland blazes - homes remained out of harm's way Thursday - biologists are turning their attention to the damaged ecosystem, particularly for the Mojave Desert tortoise.
"It's hard for me to see this fire," said Ann McLuckie, a biologist for the Utah Division of Wildlife Resources. "It's heart-wrenching to see the impacts on the fragile ecosystem and the tortoise population."
Thursday, biologists and wildlife managers toured the Red Cliffs Desert Reserve just north of St. George in an effort to analyze the impact from this week's fires.
It is estimated that wildfires fueled by cheat grass and fanned by erratic winds burned more than 10 percent of the 62,000-acre wildlife preserve.
The Red Cliffs preserve is home to an estimated 1,700 tortoises. Officials fear than many may have perished in the blaze.
"The tortoise is an umbrella species - it alerts us to threats to other species because it's easy to monitor," McLuckie said.
Beyond the reserve's boundary, much of the 12,000 acres scorched this week in various Washington County fires comprise desert tortoise habitat.
Like many parts of this hot, dry landscape, the Red Cliffs preserve, after a wet winter and spring, is choked with fast-burning cheat grass.
Because lightning ignited the fires on a relatively cool day, many tortoises would have been out of their underground burrows, McLuckie explained.
"For the juveniles and sub-adults, it could have had a huge impact," she said.
"We won't know for sure for a year or two."
Although desert tortoises - a federally "protected" species - are believed to live to be 50 to 60 years old in the wild, and perhaps longer, they are not efficient at producing offspring, said Lori Rose, a Washington County habitat biologist.
An adult female - age 20 or older - may lay up to 15 eggs per year, but only one-third hatch.
And only 2 percent of turtles that hatch live to reproductive age.
The invasion of cheat grass, a non-native species, is drastically altering the wildfire cycle and is impacting the tortoise and other species, Rose said.
"But no one yet knows how the desert will respond."
Whether species such as the desert tortoise survive could depend on what scientists can devise to stop the quick spread of cheat grass, according to Randy Trujillo, a Bureau of Land Management field manager.
In the St. George area, the Mojave Desert ecosystem comes together with the systems in the Great Basin and Colorado Plateau.
In this unique area, the fire cycle should be 35 to 50 years, Trujillo said.
With the invasion of cheat grass, the fire cycle has jumped to every three to five years, he said.
That makes it nearly impossible for native plants to compete with the onslaught.
"The cheat grass burns before the native plants can set seeds," Trujillo said.
"But if we can slow the fire cycle down, the native plants can re-establish themselves."
Biologists are exploring ways to keep cheat grass from spreading, such as reseeding burned areas with native plants.
But like a cure for cancer, it could take awhile, he said.
"You won't see a cure anytime soon," he said. "But it won't be long before you should see some progress."
l Jarvis fire: 900 acres, fully contained.
l Blue Springs fire: 12,286 acres, 80 percent contained.
l Diamond Valley fire: 6,500 acres, less than 50 percent contained.
l Plateau fire: 2,800 acres - less than 50 percent contained.
l Wide Canyon fire: 1,700 acres, less than 50 percent contained.
l Cottonwood fire: 324 acres, less than 50 percent contained.