A conservation group said it sent over 100 bison to tribes in Montana, South Dakota and Washington.
American Prairie sent 107 bison from its herd in eastern Montana to five tribes in November. Twenty-one were sent to the Blackfeet Nation and Rocky Boy tribe.
The conservation nonprofit distributes bison to tribes every year. The InterTribal Bison Council said this helps tribes build their herds and diversify genetics.
The bison are tested for brucellosis and other diseases before they are sent to tribes.
American Prairie said the distribution also helps it maintain its own herd, which now stands at about 900.
Restoring bison to the landscape is culturally important for tribes, which relied on the animals for centuries.