A private conservation reserve on north-central Montana's open prairie now spans more than 300,000 acres with the addition of a large parcel south of Malta.

American Prairie Reserve manager James Barnett said Thursday the group recently bought a 22,000-acre ranch in Phillips County.

He says the deal marks an important step in the reserve's goal to piece together more than 3 million acres of public and private lands. That would allow the free flow of wildlife -- including up to 10,000 bison.

The reserve is about 60 miles south of Canada and connects with the C. M. Russell National Wildlife Refuge.

Some surrounding ranchers worry the project will doom the remote area's agricultural communities.

Owners of 14 ranches have voluntarily sold out to the reserve since 2004.