RENO, Nev. (AP) — U.S. land managers have begun efforts to capture about 50% more wild horses than originally planned this year because of severe drought across the U.S. West.

The emergency roundups that began Sunday and Monday target about 6,000 additional animals primarily in Nevada, Oregon and Colorado.

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The Bureau of Land Management says the expanded effort concentrates on places where “chronic overpopulation” of the herds has stretched available food and water to their limits. Horse advocates say the emergency roundups are being driven by pressure from ranchers who don’t want wild horses competing with their livestock for limited forage and water.

The National Cattlemen’s Beef Association says ranchers have voluntarily reduced and rotated grazing on federal lands during the drought.

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