The federal agency says mustangs in the Antelope and Antelope Valley Herd Management Areas are moderately thin to very thin because of minimal forage and limited water.
BLM says the condition of the animals will deteriorate if steps are not taken to remove them.
A helicopter will be used to gather the horses in the areas located 60 miles south of Wells and 50 miles north of Ely. The roundup is scheduled to begin Oct. 1.
Horses removed from the range will be taken to either Palomino Valley north of Reno or the Gunnison Correctional Facility in Utah to be prepared for adoption or sent to long-term pastures.