Fly Fishing Slough Creek Yellowstone National Park
Slough Creek rises in southern Montana in the Absaroka-Beartooth Wilderness and flows southwest into Yellowstone National Park. It empties into the Lamar River near Tower junction within Yellowstone National Park. In turn the Lamar River forms a confluence with the Yellowstone River inside of Yellowstone National Park. Slough Creek is a mildly alkali stream. The Slough Creek watershed consists of mixed fir forest, sage flats and grassland. These plant communities support considerable wildlife including coyote, bears, wolves and bison.
Slough Creek ranks as one of the most popular fishing destinations in Yellowstone. While access can be relatively easy - the fishing for large cutthroats can be a challenge. The lower meadows of Slough Creek, below the campground, are easily accessible from parking areas between the campground and the Cooke City road. There are rainbows in this lower water as well as cutthroats. The upper meadows of Slough are accessed from a trailhead near the campground. The first meadow is a 45 minute walk from the trailhead with an initial uphill climb. The first meadow is the most popular since it's close and the fishing can be excellent. Slough Creek's second meadow is about a 3 hour hike.
Cutthroat trout in Slough offer good dry fly fishing with heavy hatches of caddis, PMDs, and large Green Drakes in July. Terrestrials can be fished in early August and are prominent in late summer. As Slough Creek meanders through large meadows, grasshoppers are numerous, as too are ants and beetles. A good hopper pattern is often the key to success and you should have a variety of them. I found both the body color and size of the hopper pattern to be important on Slough Creek (i.e., bigger isn't always better).
In the summer of 2007 an angler caught a rainbow trout upstream of the Slough Creek falls. Not welcome news to the Park's fisheries biologists who are engaged in a full-scale war to remove lake trout from Yellowstone Lake. The presence of of rainbow trout ulimately impacts the native cutthroat trout as well as other wildlife species who count on the cutthroat as a food source. The National Park Service requires anglers to kill any brook or rainbow trout caught in the Lamar River Drainage, including Slough and Soda Butte Creeks.