Federal authorities will intervene at Mono Lake, where a burgeoning wild horse population has expanded beyond its designated territory, causing significant harm to the fragile and unique ecosystem. The U.S. Forest Service, in partnership with the Bureau of Land Management, has approved a plan to round up and remove several hundred horses that have migrated into the Mono Basin from their territory about 30 miles to the east. The action aims to mitigate ongoing damage to sensitive habitats and address public safety concerns but has drawn criticism from animal welfare advocates and local Native American tribes.
The conflict pits the protection of a vital, internationally recognized bird habitat against the management of an animal often seen as a symbol of the American West. An aerial survey in 2024 counted nearly 700 horses in a region federal officials say can only sustainably support between 138 and 230. This overpopulation has pushed hundreds of horses into the Mono Lake area, where they are trampling pristine wetlands, degrading freshwater springs, and damaging the lake’s iconic tufa towers. While environmental groups and federal officials argue the removal is essential for preserving the lake’s ecological integrity, opponents are challenging the methods and calling for a more humane, collaborative approach to managing the herd.
An Ecosystem of Extremes
Mono Lake is an ancient, landlocked sea with water more than twice as salty as the ocean and a highly alkaline pH of 10. While inhospitable to fish, these extreme conditions support a simple but massively productive ecosystem. The food web is built upon trillions of endemic brine shrimp, Artemia monica, and vast clouds of alkali flies that thrive in the saline water. These two species provide an essential food source for millions of birds that use the lake as a critical resting and refueling stop along the Pacific Flyway, a major migratory route.
Because of its importance for avian life, the area has been designated as part of the Western Hemisphere Shorebird Reserve Network. Up to 80 species of migratory birds, including vast flocks of Eared Grebes and Wilson’s Phalaropes, depend on the lake’s invertebrate bounty to gain the necessary body fat for their long journeys. The landscape is also famous for its dramatic tufa towers—limestone spires formed by the chemical reaction between calcium-rich freshwater springs and the carbonate-filled lake water. These formations, along with the surrounding wetlands and alkali meadows, form a delicate habitat that has evolved over thousands of years.
An Expanding Herd’s Footprint
The wild horses are not native to the Mono Basin. They belong to the Montgomery Pass Herd, which has a federally designated territory of about 50,000 acres primarily in Nevada, roughly 30 miles east of the lake. In recent years, the herd’s population has surged far beyond what its territory can sustain. A 2020 aerial survey counted 642 horses, with nearly 500 found outside their designated range; by 2024, the estimate had grown to 699 animals. This population pressure has driven large groups of horses westward in search of food and water, into the sensitive lands surrounding Mono Lake.
The impact of hundreds of these large animals has been severe. Federal officials and environmental groups have documented extensive damage, including the trampling of wetland vegetation that provides crucial habitat for shorebirds, ducks, and songbirds. The horses congregate at freshwater springs, fouling the water and compacting the soil. They have been observed using the irreplaceable tufa towers as scratching posts and have left large amounts of manure across popular visitor areas. After one particularly harsh winter, horse carcasses were found along the shore, providing further evidence that the landscape cannot support the herd’s current size. Furthermore, the increasing presence of horses near major roads like Highway 395 poses a growing safety risk to motorists.
Federal Agencies Announce Roundup
In response to the escalating damage, the U.S. Forest Service and the Bureau of Land Management jointly approved a management plan in March 2025. The plan authorizes the agencies to gather and remove between 300 and 500 excess wild horses from areas outside the Montgomery Pass Wild Horse Territory, with a high priority placed on the Mono Basin. The operation could begin as early as the summer of 2025.
The stated goals of the roundup are to protect sensitive natural resources, including habitat for the bi-state greater sage grouse, and to reduce public safety hazards. According to the agencies, removing the horses that have strayed far beyond their managed territory is authorized under the Wild Free-Roaming Horses and Burros Act of 1971. Captured animals would be transported to off-site holding facilities. Officials state the action is necessary to prevent further irreversible harm to the Mono Lake ecosystem and to bring the herd’s population back to a sustainable level within its intended range.
Controversy and Opposition
The planned roundup has been met with significant resistance from animal advocacy organizations and local Paiute tribes. A major point of contention is the proposed use of helicopters to drive horses into traps, a method that critics say is cruel, terrifying for the animals, and can lead to injury and death. American Wild Horse Conservation and other groups have called for a halt to helicopter roundups, advocating instead for the use of on-range fertility control to manage the population humanely.
Tribal Calls for Alternative Management
Local Indigenous communities, including the Mono Lake Kootzaduka’a Tribe and the Utu Utu Gwaitu Benton Paiute Tribe, have voiced strong opposition to the federal plan. They argue that the horses hold deep cultural importance and that tribal authorities should lead management efforts. These groups have proposed an alternative plan that includes a two-year moratorium on roundups, the establishment of a Tribal Wild Horse Management Council, and the creation of a tribe-operated training and adoption facility. Despite consultation, federal agencies ultimately decided against incorporating these tribal recommendations into their final decision.