ST. GEORGE — The hot topic was conservation at the 48th Annual Desert Tortoise Symposium, where a Southern Utah biologist took a deep dive into Southern Utah’s long history of tortoise study and recovery last Thursday.
Beginning in 1936, scientists Angus Woodbury and Ross Hardy were two of the earliest individuals researching Mojave Desert tortoises. The two men conducted a 12-year study on the Beaver Dam Slope, researching the reptiles’ biology and ecology, Ann McLuckie, a wildlife biologist with the Utah Division of Wildlife Resources, said.
The Beaver Dam Slope is near Old Dixie Highway 91 in the southwest corner of Washington County and is part of the Northeastern Mojave Recovery unit, St. George News reported in a previous article.
Woodbury and Hardy were the first to document tortoise hibernation dens, wintering behavior and population density, estimating that there were approximately 58 tortoises per square kilometer, McLuckie said, adding that these findings served as a basis for subsequent research.
“Sadly, Woodbury actually died in 1964 in a car crash, but Hardy continued to visit the site,” she said.
Hardy was concerned about declining tortoise numbers on the Beaver Dam Slope and how the reptiles were impacted by various factors, including livestock grazing, vandalism of wintering dens and over-collection, McLuckie said. People reported “truckloads” of tortoises being transported to Las Vegas, Nevada, to be sold at pet stores or given away for free at gas stations.
Utah began protecting desert tortoises in 1971 and funded additional research on the Beaver Dam Slope in 1973, spearheaded by Eric Coombs, McLuckie said. The seven-year study focused on food habitats, scat analysis and grazing impacts. Additionally, researchers first reported nasal discharge in a tortoise in 1975.
The Beaver Dam Slope population of Mojave desert tortoises was listed federally as a threatened species in 1980 and 39 square miles of critical habitat was identified, McLuckie said.
Additional studies were conducted, focusing on population density, distribution and demographics in the area and comparing survival rates between native tortoises and released captives.
From 1985-1995, there was a multiagency effort to research tortoise disease mortality, as more than 150 shell remains were pulled from the Beaver Dam Slope and stored by the Utah DWR, McLuckie said, adding that an increase in nasal discharge was reported. A health assessment was conducted to better understand the health profile of the species, particularly free-ranging tortoises.
As a direct result of these concerns, the Beaver Dam Slope tortoises were emergency listed under the Endangered Species Act in 1989, and the species was listed as threatened range-wide in 1990, McLuckie said.
Once the species was listed, recovery units were formed across its range, including two located in Utah. The Upper Virgin River unit is entirely within the state and encompasses the Red Cliffs Desert Reserve. The Northeastern Mojave unit contains the Beaver Dam Slope. The DWR has monitored tortoises in these areas for over 30 years.
The Upper Virgin River unit is the smallest, containing 1% of the habitat in the recovery area, McLuckie said. It was created due to its high-density tortoise population and “high-quality habitat.”
“But we also knew that because of the small size, intensive management would be required to maintain tortoises into perpetuity,” she said.
In the early 1990s, “urban growth exploded,” increasing development pressure throughout Washington County, McLuckie said. To reduce conflicts between developers and conservationists, the Red Cliffs Desert Reserve was created under the Washington County Habitat Conservation Plan in 1996, protecting over 62,0000 acres.
After the Omnibus Public Land Management Act of 2009 was passed, federal lands in the reserve were designated as the Red Cliffs National Conservation Area. The Beaver Dam Slope also was protected as part of the Beaver Dam Wash National Conservation Area, McLuckie said.
Since 1995, the DWR’s focus has been working cooperatively with local, state and federal agencies to “manage and recover tortoises,” she said. The agencies’ efforts include acquiring over 10,000 acres of private property and installing and maintaining 82 miles of tortoise fencing.
The division has “taken the lead” in habitat restoration and tortoise translocation, McLuckie said. Approximately 575 displaced tortoises were moved into the Babylon area, which includes the Babylon Arch trail and Sandstone Mountain.
If tortoises are present on property that’s set to be developed, the Red Cliffs Desert Reserve and partners can capture the animals for relocation, as St. George News previously reported. The reptiles are medically evaluated before release.
The tortoises are given a “hard release,” where they are soaked in water to ensure they are fully hydrated and then left near existing burrows or in the shade.
The division released tortoises monitored from 2003 to 2018, focusing on impacts on density, health, survival, growth and other factors. Translocation was determined to be a success in Southern Utah after researchers saw positive signs, including an increase in population density and a “relatively high” survival rate, McLuckie said.
To restore desert habitat impacted by wildfires, the division tapped into funds from the Watershed Restoration Initiative and other agencies to replant over 10,000 plants on the Beaver Dam Slope and in the Red Cliffs Desert Reserve from 2026-2017 and more than 900 willow and cottonwood trees from 2020 to 2021.
In 2006, the reserve obtained the Turkey Farm Property, which, while within its boundaries, was not initially included in the Habitat Conservation Plan as it was a working farm. The structures were demolished and removed, and the soil was prepared and drill-seeded. Additionally, multiple agencies have used the property to experiment with habitat restoration methods.
The division’s current goals include conducting additional field surveys on the Beaver Dam Slope, maintaining its local roadkill mortality database, experimenting with cost-effective habitat restoration strategies, and pursuing “innovative solutions” and collaborative partnerships.
In conclusion, McLuckie recited a quote from Coombs.
“‘The desert tortoise in the state of Utah is unique as its controversial, and its future and habitat are hinged on the choices made by responsible land management agencies and politicians,”‘ she said. “So that was true in 1980. And it’s true today.”
The Desert Tortoise Council made the abstracts for presentations available at this link.
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