Photo of the Day #157: Bison

The American bison (Bison bison) was almost entirely lost by the beginning of the 20th century, but a number of conservation projects sprang up during this time to try and restore bison populations. The individual animal photographed above calls the Bronx Zoo home, and the institution has a history of bison conservation; in 1905 the American Bison Society was founded at the zoo (with Theodore Roosevelt as honorary president), and by 1907 15 bison were on their way west.

Despite the efforts of conservation groups, though, the number of bison presently roaming North America is just a shadow of the immense number of bison that used to thunder across the plains. Even more troubling is that many bison populations have been cross-bred with cattle or European bison, and groups of genetically intact American bison are rare. Presently, the only population that is genetically intact and remains in the area it historically inhabited is the Yellowstone National Park group, but animals that wander outside the boundaries of the park are often shot as ranchers claim they could transit diseases to cattle. More information about the controversy surrounding migrating bison and the Yellowstone population can be found in the book No Way Home.