Annual Bison Roundup returns to Antelope Island State Park in October

A bison calf grazes alongside the herd at Antelope Island State Park, where the annual Bison Roundup will take place Oct. 25, 2025. Photo: Antelope Island State Park

ANTELOPE ISLAND, Utah — The annual Bison Roundup at Antelope Island State Park will return Oct. 25, giving the public a chance to witness hundreds of horseback riders drive nearly 800 bison into holding corrals as part of an effort to manage one of the nation’s largest and oldest public herds.

The roundup begins at 9 a.m. at Fielding Garr Ranch and moves north across the island. Spectators can view the final push from White Rock Bay, where food vendors, educational booths and family activities will be available. Vehicle access along the east side road will be restricted for safety. Past roundups have concluded between noon and 3 p.m., though officials note the timing depends on the animals’ behavior.

The event marks the first of two phases. During the initial phase on Oct. 25, riders consolidate the bison into a single herd and move them into corrals, where the animals rest for about a week to reduce stress. Public riders may participate with registration.

The second phase, known as the Working of the Bison, will take place Oct. 28–30. Each bison will be vaccinated, examined for health issues and pregnancies, and tagged with a radio frequency identification chip. Following the checkups, animals are either released back onto the island or kept for sale in a public auction. Free tours and media opportunities will be available during this phase, though group reservations must be made in advance.

To maintain a sustainable herd size of about 500 to 550 animals, excess bison are sold at auction. Without natural predators on the island, park managers say it is necessary to reduce herd numbers to balance the food supply with other wildlife, including pronghorn, bighorn sheep and mule deer.

Revenue from the sale supports Antelope Island’s Wildlife and Habitat Management Program, which funds habitat work and infrastructure improvements. The 2025 auction will take place online Nov. 5.

Antelope Island State Park is open daily from 6 a.m. to 10 p.m. For more information, visitors can call 801-773-2941 or 801-725-9263.