By Chris Rourke Along a more than four-mile stretch of the Slate River near the town of Crested Butte lies a colony of Great Blue Herons. They return every spring to lay eggs, hatch their brood and tend to chicks. The majestic and colorful creatures can be spotted high in the tree tops overlooking the river, with their blueish-grey plumage and long plumes fluttering in the breeze. Unfortunately, they too spot recreationists that use the waterway below—floaters as they’re called—the sight is simply too upsetting for them. “What we’ve seen is a clear and dramatic pattern that proximity leads to ...