Bison question is complex

Letter writer Don Chapman criticizes Garrett Wilson [“Refugee Crisis,” February-March 2017] for not calling the disappearance of the bison from the northern plains a systematic slaughter. It’s not that simple. A new collection of essays [co-edited by the writer], Bison and People on the North American Great Plains: A Deep Environmental History, offers a more comprehensive explanation for what happened — how it was a combination of factors and not only a consequence of indiscriminate killing by white hunters. The story is complex, nuanced, and interesting. Bill Waiser Saskatoon