The Bureau of Land Management is planning to round up wild horses near Craig in October.
The Daily Sentinel reports that some of the horses will be treated with a fertility control drug and about 50 young horses will be removed and placed into a nonprofit training and adoption program.
BLM officials estimate the Sand Wash herd near Craig has more than 600 horses.
The agency decided last week to proceed with the roundup and thus far there have been no legal or administrative challenges to the action. A 30-day administrative appeal period is now in effect, and the earliest the gather could begin is Oct. 21.
BLM spokesman David Boyd says it is not uncommon for legal or administrative challenges to come closer to the planned start date.