Spring runoff usually subsides between mid May and mid June. Once the flow drops, the upper Beaver River can provide good fishing for abundant brown and rainbow trout throughout the summer. Most of the tributaries - including the Beaver forks, Merchant Creek, and Three Creeks - also have abundant populations of wild trout. A variety of flies, lures, and natural baits can produce good to excellent fishing. Terrestrial flies like foam hoppers and ants can provide some exciting action during the summer. Focus fishing efforts on early morning and late afternoon/evening.