I was there in mid July and was nearly eaten alive by deer flies. The Yellowstone drainage is increasingly non fishable due to rain and run off although Lamar is more prone to this than Slough. This problem has apparantly gotten progressively worse in recent years and one local believes that the cutthroat throughout the Yellowstone are suffering both in size and numbers. Slough was off color the day I was there but the flies were more of a limit than the water. The same local fisherman who had described the run off problems related a story about being charged by a buffalo two summers ago on the Slough. He escaped by running emiting a trail of bear spray and jumping over an embankment into the creek. The moral is take your bug and bear spray and give the buffalo wide birth.