PRINEVILLE, Ore. — The U.S. Forest Service will reduce the wild horse population east of Prineville to a level that horse advocates say could lead to the herd’s elimination.

The most recent count of wild horses on the Big Summit Wild Horse Territory of the Ochoco National Forest puts the population around 130, but the Forest Service estimates it at closer to 150, Oregon Public Broadcasting reported.

The management plan approved Friday will decrease the herd to 47-57 horses total over the next five years. Officials say “excess” horses will be captured and relocated to corrals where they will be put up for adoption.

“We want to make sure that we manage this herd for its genetic viability,” said Kassidy Kern, public-affairs officer for the Ochoco National Forest and Crooked River National Grassland. “We want to make sure it’s a healthy herd.”

The agency will use contraception and sterilization to keep the wild horse population down and will use genetic analysis to guide future management of the herd. The Forest Service said it will not euthanize horses as part of this plan.