Re-introduction of bison to the Wind River Ranch in northern New Mexico and Native American lands in the western USA

Summary

American bison (Bison bison), Near Threatened after being reduced from an estimated 30 million to about 1,000 animals by the 1880s and still managed almost entirely for meat rather than conservation today, were reintroduced to the Wind River Ranch in northern New Mexico as a joint conservation and cultural restoration effort with the Inter-Tribal Buffalo Council, which has restored 15,000 bison to tribal lands across 51 reservations since 1992. Beginning with nine bison grazed for the Jicarilla Apache Office of Cultural Affairs in 2007, the herd grew through a 2008 donation of 35 more animals and the 2009-2010 purchase of a dozen bison from the Picuris Pueblo, reaching 68 individuals split evenly in ownership between the ranch and the Jicarilla Apache. Herd size is deliberately managed relative to grass availability, calculated annually by mapping forage conditions and converting the herd into 450-kilogram adult equivalents to estimate sustainable winter grazing capacity, with excess animals transferred to other tribes, sold for meat, or distributed through a tribal free-meat program. Genetic analysis identified both a Yellowstone-lineage contribution and a previously undescribed lineage, and a pilot study and a master's thesis found bison browsing controls the encroachment of piñon, juniper and yucca onto grassland, a role compared to elephants in African savanna, with a five-year study and a Denver Zoo comparison of bison versus cattle impacts now underway. Difficulties included limited grant funding and the ranch's modest size constraining herd capacity. The project rates itself successful, crediting bison's strong fecundity and effective cooperation between the ranch and the Inter-Tribal Buffalo Council.