Slough Creek is among the most famous trout fishing destinations in western United States, and for good reason. The Cutthroat Trout are both good sized and abundant, and all of the fishing is done with dry flies. Wildlife is commonplace in the meadows of Slough Creek, and I have spotted Bison, Wolves, and Grizzly Bears all within the same afternoon of fishing. While much of the stream requires an overnight stay in the backcountry, and the coveted permit that goes along with such a trip, there are several sections that can be fished as a day trip. Rising to the north of the park in the Absaroka-Beartooth Wilderness Area, the Yellowstone Park stretch consists of 4 major meadows, broken by short pocketwater areas in small canyons. Slough Creek is hallowed ground in the fly fishing world, and every serious angler owes it to him/herself to test their skills against these wily Cutthroats at some point in their fishing career.
Fly Fishing Slough Creek - Overview
Slough Creek is divided into 4 meadows, named, from top to bottom: Third, Second, First, and Lower. The top portion of the Lower Meadow is roadside, but everything else requires hiking. From the road access below the Slough Creek Campground, it is about a 1.5 mile hike down to the VIP Pool, which lies at the end of the Lower Meadow, just upstream from the confluence with the Lamar. From the trailhead at the campground, it is 2.5 miles to the First Meadow, 4 miles to the Second, and 6 miles to the Third. It is almost 11 miles from the trailhead to the end of the Third Meadow and the park boundary.
The 1st, 2nd, and 3rd meadows have good populations of Cutthroats that average in the 14”-16” class, with fish up to 20” present. The main difference in each meadow is the amount of fishing pressure, which lessons somewhat as you get farther from the road. While size and numbers stay the same, the fish further upstream are often easier to catch. The First Meadow is an easy day trip, while the Second is only feasible for the very fit, experienced hiker. The Third Meadow requires an overnight stay. That said, chances are you will still have competition from other anglers in the 3rd Meadow.
The Lower Meadow is a different beast altogether. A significant tributary, the Buffalo Fork, enters between the First and Lower Meadow, greatly increasing the size of Slough Creek. Rainbows and Cutt-Bows are common in the Lower Meadow as well, with the top end fish falling in the 22”-25” range. The river here is not only larger, but deeper and slower as well. I have seen fish cruising here, swimming and facing downstream as well as up. Heavy fishing pressure ups the ante even more. Nothing comes easy here.
Fishing Slough Creek - 1st, 2nd, and 3rd Meadows
Slough Creek comes into fishable shape around the 4th of July and fishes thru mid/late September. Early season is typically easiest, as the fish become increasingly wary as fishing pressure mounts throughout the summer. In July, mayfly hatches and hoppers are the attraction. In August and September, hoppers still work but smaller terrestrials like beetles and ants become key as the trout will have seen every hopper pattern under the sun. The slow, clear waters of Slough Creek lend themselves to sight fishing, and the angler who is able to slow down and think through each situation has the advantage. Blind fishing can be productive, but your odds increase greatly if you are able to spot the fish first. Keep a low profile and try to avoid walking on the high, undercut banks. Not only can the fish spot you easily, the vibrations will spook fish that are holding along or just under the bank, key structure here. The choppy riffles at the head of each bend pool are typically the most forgiving water and easiest to fish blind. The fish in the tailouts of each pool will be spookier, and these areas are generally not productive to fish blind.
In July, be on the lookout for various species of Drakes as the most important hatch. Also come prepared to fish Pale Morning Duns and midges. A full compliment of terrestrials is essential as well, but if you are dead set on fishing hoppers, mid-late July is the time to be on Slough. In August and September, I will often start the day off with a small hopper, but I am quick to change if I get a refusal and feel I made a good presentation. Ants and Beetles will be the go to, but do not discount the importance of midges on Slough Creek.
The fish do not become active until the bugs do, whether it be mayflies or terrestrials. Use the early-mid morning hours to hike in to your desired location and get your gear rigged up. 5x tippet is the norm on Slough Creek, and be prepared to lengthen your leader a bit longer than you might otherwise fish.
Fishing Slough Creek - Lower Meadow
The Lower Meadow fishes somewhat similarly to the above, though there is an added importance of both hatches and sight fishing. Given the larger stream size and propensity of the trout to cruise, locating the fish is the first challenge in the Lower Meadow. While there are some nice riffles, pools, and banks that can be fished blind, many stretches of the creek are very uniform and tough to read without any clues from the fish. You have to choose what style you want to fish here. You can hop around, cover a lot of ground, and fish the water. Or, you can really slow down, be patient, pay close attention, and fish to individual fish.
One thing to really pay close attention too in the Lower Meadow are the many micro currents that may impart drag onto your fly. Oftentimes taking one or two steps in a given direction will make a world of difference in how your presentation appears to a fish. Watch closely to how your leader behaves as it floats downstream, as that cues you in to how your fly is about to react and you can adjust accordingly.
Look for the same variety of bugs in the Lower Meadow that you would find up above. You will want to lengthen your leader into the 12-15 foot range, and it is wise to carry 6x tippet as well. Remember that Cutthroat Trout rise and eat flies very slowly and deliberately, so remain calm and do not set the hook until you see the fish turn its head and start to dive.