The 1st edition was my fishing reference for nearly twenty years. I’m glad to see this update as the authors recognize things have changed since then. In the intervening time the Yellowstone cutthroat nearly disappeared. Thanks to extraordinary methods the trout is making a comeback; this is critical since nearly sixteen species depend on the Yellowstone “cutt”. There are now deliberate efforts to preserve native fish species and grow populations westslope cutthroats and Graylings in their historic ranges. Climate change has affected the aquatic food of trout. The caddis Nectopsyche and the mayfly Epeorus albertee were once insignificant but because of warmer waters these are dominant sources of trout food. Because of warmer winters the Spruce Moth have infested trees and become food on the rivers.