Anyone know the Origins of the Boston Bruins NHL team's bear on their shoulder patch?

Also where does the yellow come into it. I saw this doentary about some parts of Canada have white and brown bears with in the same species. Its a genetic mutation and the bears with the white fur have a bruin glow to their fur as they move. I was wondering if its possible this is where the yellow came into their franchise. What does the brown in the clevland browns refer to. I figure it has something to do with stains but I'm not sure. Stains of old textile mills of course.