Woodland zoo. The Zollman Zoo at Byronn will be closed through October 6 to replace boardwalk trails with asphalt. The bison, elk, deer and natural playscape will still be accessible, announced Olmsted County, which operates the zoo. The new trails will be more accessible and safer, the County said\. The rest of Oxbow Park, including the nature center, hiking trails, and public programming will remain open.