Francisco Kjolseth | The Salt Lake Tribune Riders from near and far numbering 430 move a herd of more than 500 bison from the rocky west side of Antelope Island during the 26th annual bison roundup on Friday, October 26, 2012.

Despite harsh weather conditions, more than 400 riders showed up Friday for the 26th Annual Bison Roundup at Antelope Island State Park. The riders moved the population of more than 500 bison to corrals on the west side of the island, where they will be held for a health checkup and, eventually, some will be auctioned off to the public.