Biology is not my area of expertise, but: Interbreeding is bad when it’s a small population interbreeding for a long long time. From the article it sounds like they aren’t worried about the genetic diversity of this 6k bison herd. I’m sure it would be better to have more diversity, but that’s hard to achieve with animals brought back from near-extinction.
There are a lot of private herds. But a lot of them have been bred with domesticated cattle and do not have the pure bison DNA in them. They can be used as a last resort. The solution here would be to slowly start separating herds to more locations away from Yellowstone. Over generations, the genetic makeup will separate enough to be considered separate populations.
