The U.S. Bureau of Land Management completed a major roundup of wild horses this week in northeastern Nevada.
The BLM said it gathered 2,196 horses from public lands in what it calls the Triple B Complex, which is about 60 miles north of Ely, between Nov. 2 and Wednesday.
Of those mustangs, the agency said it treated 23 mares with GonaCon-Equine, a fertility control vaccine, and released them back into the wild along with 16 stallions.
The BLM used helicopters operated by contracted pilots to drive the horses into traps.
The agency euthanized 27 horses during the operation, according to a web page it set up for the Triple B Complex "gather."
Of those, 20 animals had pre-existing conditions such as blindness or "low body condition" and seven were euthanized for acute reasons, including three cases of broken necks.
The BLM sent more than 2,100 horses to holding facilities in Fallon and Sparks to be readied for adoption or sale.
According to the BLM's list of planned wild horse and burro roundups this fiscal year, the Triple B Complex gather was expected to be largest in the western states and by far the biggest in Nevada.
The BLM regularly rounds up feral horses and burros - often the descendants of formerly domesticated mining and ranch animals - to address what they say is overpopulation on ranges that cannot support the animals, which reproduce readily and have few natural predators.
"The gather was crucial to ensuring public land health, as well as the health of the horses. Both continue to be at risk due to herd overpopulation," Ely District Manager Robbie McAboy said in a statement.
The BLM said the wild horse population in the Triple B complex prior to the roundup was estimated at 3,335, while the "appropriate management level" is 472 to 889 horses. The appropriate management level is the level at which the BLM says the land can support the animals.
The BLM's next Nevada roundup is planned for January, when it aims to gather about 200 horses from public lands near Eureka.
The agency plans to gather about 11,000 animals across eight western states this fiscal year, which runs from October through September.