The big Park fishing event is brown trout migration. This is big time in numbers into the Madison River, but even more numerous into the Lewis River between Lewis and Shoshone Lakes and into the river below Lewis Lake. Streamer presentation is the name of the game. Use stout leaders and rods of at least six-weight. Be ready for changes in the weather towards cold and stormy because these conditions seem to make the browns most active. Bring a camera because you have the chance of encountering the fish of the year.