Study Shows Yellowstone Bison are a Single Breeding Herd

A new study by Texas A&M College of Veterinary Medicine and Biomedical Sciences (VMBS) has found that Yellowstone National Park’s bison population, once thought to be two distinct herds, has become a single, interbreeding population of 4,000 to 6,000 animals. Published in the Journal of Heredity, the study suggests that Yellowstone bison should now be managed as one genetically healthy herd.

Yellowstone’s bison are the only continuously wild American bison in the U.S., surviving since prehistoric times. However, they faced near extinction in the early 20th century due to overhunting, with only 23 wild bison remaining. Conservation efforts, including reintroducing domestic bison in 1902, helped rebuild the population. Researchers analyzed 282 tissue samples from different park regions, confirming genetic mixing. These findings will guide future conservation efforts, ensuring the long-term stability of this iconic species. The study provides crucial data for managing genetic diversity in Yellowstone’s bison population.