The Eddy Line: ‘Tis the stonefly season
By Patrick Straub EBS Fishing Columnist
The transition from spring to summer in mountain country is defined by change: The snow line creeps up, rivers are full and often dirty, and the fly-fishing community is gearing up for summer. When I’m not on the river, I’m checking streamflows and weather reports to find stable, or dropping, rivers. With the anxiety of runoff season, a little sweat equity can result in finding some of the best fishing of the year.
If finding fishable water is the challenge, fortunately your fly choice and fishing methods are often simple. High and dirty rivers mean stoneflies are on the move. Plecoptera is the Latin name for the order of stoneflies, but with more than 3,500 species worldwide, we don’t have room in our fly boxes for them all. Stick to the common names of stoneflies and you’ll be able to talk the talk.
Salmonflies are the first stoneflies to hatch, followed by golden stoneflies, and yellow stones and sallies later in summer. Despite their differences, all stoneflies hatch in similar ways – by crawling to bankside structure and shedding a nymphal “shuck,” or shell, and emerging as flying adults. We’re still several weeks away from the emergence of adult salmonflies, but if you want to catch fish before the hatches and the masses of anglers arrive, you need to understand how to fish stonefly nymphs.
Bank on it. Stoneflies need structure to hatch. With very few exceptions, they crawl from the water onto rocks, sticks or other shoreline objects. As these nymphs are migrating to shore, hungry trout gobble up as many of them as possible. It’s as if the fishing gods created this hatch so we could fish during runoff – since the trout’s main food source is near the bank, we can still fish during high-water periods. With rivers that are bank-full, wading into swift current is unsafe. It’s a good thing that nearly all your fishing should occur while standing near, or even on, the bank.
Shorten and strengthen the system. Since the fish are close to the banks, decrease the length of your leader and increase the strength of your tippet. Additionally, a shorter leader will be easier to cast larger, heavier flies. The occasional branch snag will occur, and a stronger tippet ensures you’re more likely to keep your flies. Increasing the strength of your tippet helps if you get snagged on the bottom as well, since dirty water makes it difficult to see underwater structure. A stouter tippet also comes in handy when you hook that trophy trout and need to land it in fast current.
Weight for it. Even though fish are tight to the banks this time of year, the current is often strong and fast. Adding weight to your fly or your leader is essential. My favorite stonefly nymph pattern is a Pat’s Rubberlegs. This fly is similar to a Girdle Bug or Bitch Creek and imitates a stonefly nymph. I tie weight into these fly, typically wrapped on the hook shank during the tying process. Adding weight to the leader in the form of putty or split shot may be helpful as well. Start with as little weight as possible then add weight as needed if you’re not getting deep enough.
Double the pleasure. Fish two flies at all times to increase your odds for a strike and for a little more weight in the rig. The second fly can be tied directly off the bend of the hook of the first fly using a clinch knot.
Strike on anything. Using a strike indicator is helpful when stoneflies are on the move. An indicator serves two main purposes: it allows you to detect a strike and it holds your flies at the right depth. If you see it move in any erratic motion, set the hook. A good rule of thumb is to place the indicator twice the depth of the water above the first fly. However, this varies based on current speed, flies on your leader, and your ability to mend effectively. I use indicators I can move easily, such as the AirFlo AirLock.
Trout eat stoneflies year round, but as spring fades into summer stonefly nymphs become more active until their emergence into adults and subsequently dry-fly fishing begins. Until the adults flutter about, you’ll need to adjust your tactics. If you don’t want to do that, I’m sure there’s a bowling league somewhere that needs a few more rollers.
Pat Straub is the author of six books, including “The Frugal Fly Fisher,” “Montana On The Fly,” and “Everything You Always Wanted to Know About Fly Fishing.” He and his wife own Gallatin River Guides in Big Sky and co-owns a guide service on the Missouri River.