Question: What Bison heard is a herd of 250–400 American bison in Wind Cave National Park, South Dakota, USA, that  is one of two subspecies/ecotypes of the American bison?
Sentence (from "Plains bison"): Furthermore, it has been suggested that the Plains bison consists of a northern ("B. b. montanae") and a southern subspecies, bringing the total to three.
Relevant evidence: No