Until a general killing frost hits the Park, terrestrial patterns will be the best dry fly way to find action during daytime hours. Tricos continue to emerge during mornings on many streams and evening caddis flights complete the reasons to find day long activity. On the Firehole River BWOs are into their classic autumn appearance. But as we approach closer to October streamer fishing will take over on most streams as the best way to encounter the largest fish. This is particularly true on the Madison River drainage below barrier waterfalls, on the Lewis River between Shoshone and Lewis lakes, the lower Yellowstone River (in the Park), and the Snake River at the south entrance. Still water fishing can also be excellent. Nowhere is action faster than on Beula Lake with Riddle Lake likely second. Both host Yellowstone cutts always eager for a meal. On Lewis and Shoshone lakes fishing away from shore remains the best way to encounter migrating browns, but fish close to shore will become increasingly effective as we advance through October.