(CN) - The government's decision to rein in the wild horse population on Montana's Pryor Mountain did not violate environmental law, a federal judge ruled.
U.S. District Judge James Gwin dismissed a challenge by the Cloud Foundation, a Colorado nonprofit that claimed the Bureau of Land Management's roundup plan threatened the viability of the herd.
The Washington, D.C., judge previously refused to block the roundup, which proceeded as planned in September 2009.
About a year later, the Colorado nonprofit and other environmental groups amended their complaint to try to block the government's planned expansion of a fence to keep the herd from damaging public land.
In December 2010, Gwin refused to dismiss the case as untimely and declined to transfer it to a judge in Montana.
On Tuesday, he granted the government's cross-motion for summary judgment, upholding the BLM's decision to limit the wild horse population to between 90 and 120.
"Against the competing claims for using this land, court finds that the agency used reasoned decision making when it picked the target horse and burro population and its actions were not arbitrary and capricious," Gwin wrote.
He also rejected the groups' bid to block fence construction, saying the U.S. Forest Service had "fully explained the need to repair, maintain and slightly extend the fence."
"The Forest Service determined that extending and realigning the fence would 'reduce long-term maintenance needs, provide an effective barrier, and minimize conflicts with other legitimate uses on adjacent National Forest System land,'" Gwin explained.
It was too late to challenge the government's exclusion of BLM wild horse roundups from the requirements of the National Environmental Policy Act, he added, because the event already happened.
And any decisions to exempt future roundups from such requirements "will be shaped by a number of factors and circumstances unique to that specific future horse gather," Gwin wrote.
"Only after reviewing BLM's reasoning behind an invocation of a categorical exclusion can a court determine if a violation of the National Environmental Policy Act has occurred," he wrote. "Therefore, plaintiffs have not challenged final agency action."
The Pryor Mountain Wild Horse Range spans more than 39,000 acres in Carbona County, Mont., and Big Horn County, Wyo., and is home to wild horses of colonial Spanish-American heritage.
Federal law requires the BLM and the Forest Service to care for and manage wild horses on land in their respective jurisdictions.
The Pryor Mountain Mustangs were the subject of the documentary films "Cloud: Wild Stallions of the Rockies," "Cloud's Legacy: The Wild Stallion Returns" and "Cloud: Challenge of the Stallions," produced by the Cloud Foundation's executive director, Ginger Kathrens.
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