When it comes to catching fish in a stream, Nevadan trout angler Steve MacMillan knows no bounds. He’ll climb any mountain, tread any path and wade through any churning body of water in pursuit of his quarry. But MacMillan is not just a fisherman. He’s essentially performing the work of a biologist as a volunteer. By diligently documenting the location, air and stream temperature, fish species, weight and length of every catch, MacMillan gives scientists an invaluable dataset to track and preserve fish populations where he goes.