Few animals carry the weight of the plains' history like the bison, which once ranged the grasslands in the millions and were driven within a lifetime to the edge of extinction. Their return — to the national park, to tribal herds, to private ranches raising them for meat — is among the great conservation stories of the continent, and a shaggy emblem of the grassland's recovery.

The Shaggy Engineers of the Prairie

The bison is more than a symbol; it is an engineer of the prairie. Its grazing, its wallowing, its very hooves shape the grassland in ways that favor a host of other creatures, from nesting birds to prairie dogs. A landscape with bison is a richer landscape, and much of the plains' ecology evolved with the great herds moving through it.

From the almanac's reckoning:

• Bison were driven nearly to extinction within a single human lifetime.
• Herds now graze the national park, tribal lands and private ranches.
• Bison grazing and wallowing shape habitat for many other prairie species.

To watch a herd graze the badlands at dusk, calves at their mothers' flanks, is to glimpse the plains as they were before the plow. The almanac counts the bison's return among the most hopeful chapters in the long story of the grasslands.