[Rain Man]

I bet the bison was trash-talking that guy at the end. "Bear spray? Bear spray? I'm gon' kick 'yo a**, puny human."

It's hard for me to find initial fault here because I can't tell who was approaching whom. If the family was on the boardwalk and the bison approached, maybe their only crime was not moving away quickly enough. If the bison was minding its own business and they came close, it's on them.

But as Wilson said, why was the one person off the boardwalk at the beginning? That's ill-advised for a number of reasons. I bet the bison view that as trespassing.