Starting Monday state officials will again be allowed to use helicopters to haze bison back into the park.
A federal district court judge approved an injunction to stop the low flying choppers almost two weeks ago, but the order expires Monday.
The Alliance for the Wild Rockies filed another injunction Friday but it was denied.
The environmental group says the hazing also harasses grizzly bears. Since grizzly bears are a threatened species, they say the activity violates the Endangered Species Act.
Judge Charles Lovell says There is no reason for the injunction while the helicopters are on the ground and wildlife advocates may refile if needed.
"We're going to wait and see what happens with the Department of Livestock and the Park Service and the Sheriff's Department and everybody down there chasing buffalo and if they take a chopper after the TRO expires, we'll file once again- the same papers, briefs that say we want the action to stop," says Alliance for the Wild Rockies' Steve Kelly.