ST. GEORGE — An area in Washington County known for its higher density of the threatened Mojave Desert tortoises is expanding.
The Utah Division of Wildlife Resources announced Tuesday that about 23 acres of land were donated toward the Red Cliffs Desert Reserve. In addition to the donation, the agency reports that another 30 acres were acquired through an Endangered Species Mitigation Fund, giving the reserve an additional 53 acres.
The new land additions were acquired through the help of the Utah Department of Natural Resources, Washington County, and The Nature Conservancy — a national land conservation nonprofit. The private property acquired was one of the largest remaining private properties within the reserve, according to DWR biologist Ann McLuckie.
"Long-term protection of this entire parcel is vital. The parcel supports high numbers of desert tortoise and provides quality habitat for a number of other desert species too," she said in a statement. "Acquisition and protection of this property is essential to maintaining the integrity and connectivity of the Red Cliffs Desert Reserve."
Dave Livermore, the Utah director of The Nature Conservancy, added that acquiring "key inholdings" within the reserve has been a priority for the group for some time.
The Red Cliffs Desert Reserve is an area of over 60,000 acres located north of St. George that's protected through the help of several local, state and federal agencies. It's considered the far northeast corner of the current range for the Mojave desert tortoise, according to the U.S. Fish and Wildlife Service.
A little over 2,000 adult tortoises are estimated to live on the Utah reserve with an estimated five to nine adult tortoises per square mile, according to the DWR. It's considered the highest population density for the species within the range.
The species, which was listed as threatened under the Endangered Species Act in 1990, is also commonly found in Arizona, California and Nevada.
A study conducted three years ago found that adult tortoise populations fell by 50% and 90% in some of the more critical habitat management units since 2004 in some areas within its range, according to the Los Angeles Times. The newspaper pointed out those statistics last October after the California Fish and Game Commission voted to give temporary endangered species status for the desert tortoise within California.
The news Tuesday came less than a week after the Fish and Wildlife Service and the Bureau of Land Management approved plans for a 4.5-mile, four-lane highway through the reserve, including close 2 miles through the Red Cliffs National Conservation Area. The plan would add about 6,813 acres of conservation to the reserve. Several conservation groups said they planned to fight the decision and/or pressure President-elect Joe Biden to reverse it after his administration takes office Wednesday.
Biologists say that urbanization is one of the biggest threats Mojave desert turtles face, especially as the areas the species calls home experiences human population growth. That's on top of fire threats. Just last year, sizable portions of the Red Cliffs National Conservation Area were scorched by the 12,000-acre Turkey Farm Road Fire.
"The same area where new homes are being built overlaps with areas where tortoises have shelters, forage sites and reproductive areas," McLuckie explained. "Predators, vehicle collisions and illegal removal are also challenges the tortoises continue to face."