the moment was captured on video and shows alaska department of fish and game biologist tom seaton leading 100 wood bison to freedom on a snowmobile .
the land mammals were freed from a temporary pen , where they had been kept for just over a week during the transition , and followed mr seaton to their new home .
they journeyed for a distance of about a mile and crossed the innoko river before reaching the grass meadows of lower innoko , which is surrounded by the yukon river that wood bison are north america 's largest land mammal .