Custer State Park.

Bison, resting & grazing in Custer State Park.

Bison, resting & grazing in Custer State Park.

Alan Morris in Custer State Park, South Dakota. In the background, some Bison are sitting in the grass.

Bison in Custer State Park, South Dakota.

Bison in Custer State Park, South Dakota.

Bison cross the road we are driving along in Custer State Park, South Dakota.

Bison, eating grass next to the minibus I was sitting in as we drove through Custer State Park.

A group of bison with their young in Custer State Park.

Young bison with its parents in Custer State Park.

A group of bison with their young in Custer State Park.

Bison in Custer State Park, South Dakota.

Bison eating grass in Custer State Park.

Bison watching its young in Custer State Park.

Young bison with its parents in Custer State Park.

Young bison taking milk from its mother in Custer State Park in South Dakota.

Young bison taking milk from its mother in Custer State Park in South Dakota.

Young bison walking next to a river & away from its mother in Custer State Park.

White-tailed deer in Custer State Park.

White-tailed deer cross the road in Custer State Park.

White-tailed deer in Custer State Park.

Bison cross the road, stopping traffic in front of the minibus I am in, going through Custer State Park.

Bison eating grass in Custer State Park.

Bison following its young in Custer State Park.

Deer in Custer State Park.

Custer State Park, South Dakota.