That is a good question and the answer is.... it depends. It really depends on the watershed and what species of salmon are in that particular water shed. Mid August is usually a transitional time in many rivers with most seeing kings and chums starting to die off and seeing the sockeye start to spawn. Other systems like the Alagnak for example with just be seeing chums start to spawn while kings and sockeye will be in full spawn, The best bet would be to go with the Early Season Bead Selection and supplement it with a couple packs of 6mm mottled beads in Tangerine, Dark Roe and Montana Roe. This would provide you with beads to fish behind spawn kings, chums and sockeye.
Best of luck on your trip!
Brad, Mike and Kayla