The Guardian: But for Bill Alldredge, a now-retired wildlife professor at Colorado State University, there is no other explanation. He started studying unit 45 in the 1980s in response to expanding ski resorts and trails systems.
linkThe Guardian: But for Bill Alldredge, a now-retired wildlife professor at Colorado State University, there is no other explanation. He started studying unit 45 in the 1980s in response to expanding ski resorts and trails systems.
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