(CNN) For the first time in nearly 150 years, bison will roam a new corner of a South Dakota national park. It's a vital step in growing the population of America's national mammal.

Badlands National Park officials released four bison into a newly expanded range on Friday. And if the way they careened out of their trailer onto the snow-covered plains is any indication, it seems the bison immediately made themselves at home.

The new real estate came from a land swap with a local ranch that blocked bison from entering the less rugged side of the park. Park officials worked with the US Forest Service and World Wildlife Fund among others to secure the additional 22,000 acres of land in 2014, according to the National Park Foundation

The project also included new fences along the perimeter of the new land to separate bison from local cattle.

Read More