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"): The Plains bison ("Bison bison bison") is one of two subspecies/ecotypes of the American bison, the other being the wood bison ("B. b. athabascae").
Relevant evidence: Yes