The Bureau of Land Management (BLM) will begin gathering up to 50 wild horses from Colorado’s Sand Wash herd management area (HMA) in October under a decision signed Sept. 21.

Beginning Oct. 21, the BLM will bait-trap wild horses in northwestern Colorado’s Sand Wash Basin to remove up to 50 young horses, which will be placed in the Great Escape Mustang Sanctuary (GEMS) training and adoption program, and administer fertility control treatments to mares being released back to the range.

The BLM said it manages the area for up to 362 wild horses, but the current population exceeds 600, a number that poses a serious risk to the area’s ecological balance. Treating mares and removing some young horses should help check the growth of the Sand Wash herd, the BLM said.

Wild horses will be attracted to corrals using bait over a series of days or weeks. While confined in a corral, BLM will work with its partner group the Sand Wash Advocacy Team (SWAT) to identify horses to be placed into the adoption program as well as mares to be treated with the contraceptive vaccine porcine zona pellucida (or PZP), which delays fertilization, and released back to the range