Wild horses from Utah’s Swasey herd are rounded up by Cattoor Livestock Roundup Co in the West Desert near the Swasey Mountains Thursday February 14, 2013. Under the Bureau of Land Management operation 50 miles west of Delta, helicopter wranglers will gather 262 horses. One hundred will be released back into the Swasey Herd Management Area — one of Utah’s 19 HMAs on federal land. Many of the horses released will be mares treated with the contraceptive Porcine Zona Pellucida (PZP-22).