TUCSON, Ariz.— The Center for Biological Diversity petitioned the U.S. Fish and Wildlife Service today to protect Bendire’s thrasher under the Endangered Species Act.

The imperiled songbirds, native to the arid lands of the southwestern U.S. and northwestern Mexico, have lost nearly 90% of their U.S. population over the past 50 years, primarily because of destructive sprawl and other forms of land degradation.

“Bendire’s thrashers are wonderful, secretive birds who depend on flat, sparsely vegetated areas in the desert Southwest,” said Krista Kemppinen, Ph.D., a senior scientist at the Center. “Unfortunately, rampant sprawl and climate change are destroying the birds’ habitat. Further population declines could push Bendire’s thrashers over the cliff of extinction.”

The 2025 U.S. State of the Birds report named Bendire’s thrasher one of the country’s 42 Red Alert Tipping Point Species — defined as bird species who have lost more than half their populations within the past 50 years and that require immediate and urgent action to address declines.

Bendire’s thrasher is a medium-sized songbird that spends much of its time foraging on the ground and often runs with its long tail cocked over its back. They are most noticeable during the breeding season, when males sing a rich, variable warble.

Unchecked sprawl is one of the major threats to the bird’s existence. Arizona, which contains about half the global thrasher population, has some of the nation’s fastest growing cities that have historically grown outward rather than up, encroaching on pristine desert habitat. The population of Maricopa, Pima and Pinal counties, which include core thrasher habitat and the cities of Phoenix and Tucson, is expected to more than double its 2005 population by 2050.

The proposed Interstate 11, a 280-mile highway between Nogales and Wickenburg, Arizona, would pave over areas where large thrasher populations live.

Another serious threat to Bendire’s thrashers is climate change. Native arid land vegetation is expected to shift northward, and the birds will go with it. However, it’s not known if this shift can keep up with the pace of climate change. Already living at the edge of its heat tolerance, Bendire’s thrashers will likely suffer from dehydration and hyperthermia and experience reduced fertility due to a hotter and drier climate.

Compounding these threats, industrial activity in the form of data centers, warehouses and large-scale solar facilities is expected to increase substantially within the thrasher’s habitat. Other significant threats include wildfires fueled by invasive species, off-road vehicles and mining, among others.

Conservationists raised the alarm about Bendire’s thrashers more than a decade ago, prompting the formation of a working group seeking to inform conservation of these birds.

“Thanks to collaborative research and monitoring efforts we’ve improved our understanding of where Bendire’s thrashers live, their habitat needs and the many enormous threats to the birds’ survival,” said Kemppinen. “Unfortunately, these efforts and conservation recommendations aren’t enough to restore populations or prevent the birds’ slide to extinction. Protection under the Endangered Species Act is urgently needed.”