"In the remote northeast corner of Montana on the Fort Peck Indian Reservation, Robert Magnan has built a fence.

Stretching nearly 42 kilometers across more than 2,000 hectares of Montana's snow swept plains, it's taken two years and $200,000 raised by the Assiniboine and Sioux tribes of Fort Peck to complete the fence.

Now Magnan waits for the last piece of the plan.

Hundreds of kilometers south of the Fort Peck reservation, where Montana and Wyoming meet in Yellowstone National Park, we find what Magnan is waiting for. Staggeringly large, burly, and grand – bison.

An icon of the country's western wild land. Magnan, who heads up the tribes' Fish and Game Department, hopes that the land enclosed by the fence will one day provide a new home to just a few of the park's iconic bison herd.

Yellowstone's roughly 3,900 bison, also known as buffalo, are the last herd directly descended from the tens of millions of American wild bison that once thundered across the Great Plains.

But the road from Yellowstone to the far reaches of Fort Peck's pasture is so far closed.

Winter in the Rockies is not for the faint of heart. Even for these bison, who have survived the harsh winds and sub-zero climate for seemingly time immemorial, it is an annual rite of survival that now brings tests beyond temperature.

During especially harsh winters – just like this season – bison often leave the park in search of food.

Once they reach the greener grass, they face a new challenge – not winter, but people.

The foraging bison are rounded up into corrals by state livestock authorities riding horse or helicopter and tested for brucellosis. The disease, which can be passed between species, causes livestock to abort their young – a condition that cattle ranchers are understandably not eager to encounter in their herds."

Get the Story:
Where the buffalo roam (Al Jazeera 3/25)

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