Try this shallow-water tactic on Idaho's Snake River Plain reservoirs: Chesterfield, American Falls and C.J. Strike. It also works in a quiet cove of Utah's legendary Strawberry Reservoir or on the less celebrated (but equally productive) Wasatch Mountains reservoirs, Currant Creek or Scofield. The upper end of southwestern Wyoming's Fontenelle Reservoir is full of trout, or you can fish for prizewinning fish at February's icefishing derby on Sulphur Creek Reservoir south of Evanston. Colorado has great winter trout lakes in North Park, and any of the interior mountain reservoirs--Ruedi, Rifle Gap, Antero and Eleven Mile--will produce limits on light tackle.