WILDLIFE: Healthy Yellowstone bison could help start new herds -- study Published: Friday, February 28, 2014 Disease-free bison in Yellowstone National Park could be used to start new herds across the West, a study shows. Please subscribe to Greenwire to read the full story. Username: Password: Forgot your access codes? Recover them. Not a subscriber? Sign up for a trial. Ready to subscribe? Click here.