As we move into the middle part of June here in Southwest Montana, one thing on the mind of trout fisherman in our area is the famed Salmonfly hatch. Why all the fuss? Well just the thought of a nice trout rising to the surface to eat an insect that reaches up over 3” long is enough to get the juices flowing in any fly fisherman’s psyche. One thing is for sure, once you experience a Salmonfly hatch and catch your first fish on one of those bugs, you’ll be hooked for life.
Salmonflies are a variety of a stonefly, Pteronarcys, that live most of their lives under the water. Salmonfly nymphs typically spend 3 years under water and once they reach maturity (typically during the month of June when water and air temperatures are just right), will actually crawl out of the water along the banks and break out of their nymph shucks appearing as the adult insect that we actually see. They have two antennas, two tails, a set of long wings and a set of shorter
wings that drape over the backs and bright orange bellies making them fairly easy to identify. Once they reach their adult stage on land, they will typically crawl off the rocks into the bushes where they mate, much like other aquatic insects. When the females are full of eggs, they will launch from the bushes, fly over the water and smack their abdomens on the surface to drop their eggs and keep the cycle going. This is the phase of their lives that will drive trout crazy.
As far as the fisherman goes, the Salmonfly hatch can be both exciting and frustrating all at the same time. There are a couple of things to mention before we dive into how to successfully catch a fish on a Salmonfly. First, unfortunately, there is no way to predict a Salmonfly hatch, or if the river will even be fishable during the hatch. As was mentioned before, Salmonflies typically hatch during the middle to end of June in our area, depending on the river. High water and the annual spring runoff also typically happen from the middle to end of June. Conditions must be just right with decent water clarity for fishing during the Salmonfly hatch to be good. Salmonflies don’t care if the water is dirty so they’ll still hatch when the conditions are right for them. Sometimes, this does happen during dirty and high water and we never get to fish with them. That’s just life. Secondly, just because you see a few skeletons along the rocks and a few bugs in the bushes does not mean that the dry fly fishing with Salmonflies is going to be “epic.” We hear this all the time from anglers who head out and come back disappointed. The fish don’t care that there are Salmoflies in the bushes. If they have not seen them on the surface of the water, they might not be in tuned to looking up. Its not until you start to see bugs flying and bugs laying eggs on the water that the fish really get worked up for them. On an aside note, this is also true for other insect hatches as well. Think about it, until fish start to see a few bugs on the water or even eat a few of them, they typically are not going to be interested. They usually aren’t going to rise to something they have not seen in pretty good numbers, so until this happens, they might not eat a dry. Thirdly, not all rivers in our area, or even all stretches of a certain river, get a Salmonfly hatch. Stoneflies by nature like faster rocky rivers and streams. While you will occasionally see a few bugs on some of our slower rivers, typically it’s the faster freestone rivers where you will see the most numbers of bugs. Rivers like the Big Hole, the Gallatin, the Upper Madison and the Yellowstone are our local rivers with the most prolific hatches. Our more silty waters like the Jefferson, the Missouri and the Lower Madison below Bear Trap Canyon typically don’t have much of a hatch if any. Also, its important to keep in mind that different stretches of the rivers themselves will often have more or less insects in them. For instance, they don’t get much of a Salmonfly hatch on the lower Yellowstone River, but once you get upstream of Livingston, you’ll see a few and once upstream of Emmigrant, you see a lot. This is not uncommon on most rivers so it’s important to know where the bugs are before you go. Lastly, keep in mind that fish do get full! If you head out to fish and the bugs have been around for a bit and the fishing is slow, sometimes the fish are “gorged” where they have eaten so many bugs that they are stuffed. When things are really happening, we’ve actually caught fish before that have live insects still protruding out of their mouths. Fish go crazy for these big insects, but once their stuffed, they won’t sometimes eat until they digest what’s already in their stomachs. Just like for you and me, this really does happen.
On to techniques and equipment…
If there is one hatch or type of fishing that will really test your casting skills, it’s fishing during the Salmonfly hatch. Remember the part about high water? With this hatch happening typically when rivers are full, many of the fish will be pushed up to the banks looking for a place to feed and rest. In addition, Salmonflies are also hanging out close to the banks of the water clinging to the bushes and low branches of trees. Add those two things together and you’ll find that often your best chance of fooling a fish during the Salmonfly hatch is to put the fly as close to the bank or bushes as possible. The most successful days of fishing I’ve ever seen during a Salmonfly hatch is when the anglers I’m with can put the fly within inches of the bank, and I mean inches, and keep it there. An accurate reach cast is extremely important for successful float fishing during this hatch. Also, remember that part about how adult females will come back to the water to lay their eggs, sometimes splatting your fly down on the water will cause a fish to react instantly. Delicate presentations are not needed during the Salmonfly hatch!
Look through the bins of any fly shop and you will see Salmonflies in multiples sizes, shapes and colors, most commonly orange or black. Flies can be very specific to certain rivers, but depending on when or where you hit the hatch seems to be the most important factor. During the early stages of the hatch, sometimes the bigger, brighter and gaudier patterns are the ones that work best. It seems like if the fish have not seen a lot of adults, they are attracted to the bright orange underbellies of the bigger size 2 and size 4 bugs. In addition, it seems like the higher floating foam patters seem to work best early on during the hatch. As the hatch goes on and the fish start to become more wary, it seems like going smaller and a little darker can be more productive. Moving to a size 6 dark orange or black pattern that rides lower but offers a good silhouette can be deadly after the fish have been seeing bugs for a few day. Also, if you’re fishing a pattern that seems to get more “looks” or “bumps” than actual full on eats, moving smaller and darker can get more fish to actually commit to the fly. Unfortunately, it seems that the harder it is to see on the water, the better the fish like it. One last thing to consider is that often times, the other insects on the water get overlooked by most anglers so throwing on something like a golden stone pattern or a caddis dry can be very productive.
Our favorite customers who gear up for a Salmonfly hatch are the ones who stop in and buy a few bugs and a 9’ 5x leaders to head out for the day. If you’re this angler, you probably will want to buy a few more dozen bugs because you’ll probably need them. If you recall, I earlier mentioned that during this hatch, the water is sometimes very high or up in the willows even and that you’ll really need to get close to the bank to catch fish. If you’re anything like me, that first cast end up a little long and landing in the willows. With 5x tippet and a big fly, my $3.00 fly just went bye bye. When fishing during this hatch with big flies on sometimes windy days here in Montana, we typically fish a minimum of 2x or 3x tippet and usually no longer than a 7.5’ leader. Again, these flies are hard to cast and when you have to fish close to the bank, it’s nice to be able to yank your fly back out of the grass and not lose it all the time. Also, typically with the water being higher, it’s also usually off color a bit so fishing a heavier leader will not spook a fish. While I would love to sell you a light leader with a bunch of flies, I’d rather you had a good experience. In addition, fishing a two fly rig which can be very effective at certain times can also hinder your ability to get the fly in close. For this reason, I prefer to fish a single Salmonfly with no dropper. These big flies are hard enough to cast as it is, plus they sometimes like to twist while in the air and with a dropper below them, you’re just asking for a tangled mess. With this said, if I’m not 100% committed to just fishing the Salmonfly, adding a dropper and moving out from the bank a bit can be a good way to turn a slow day into a productive one.
So is it all worth it? Sometimes crowded waters, hard casting, the ever impending risk of losing lots of flies and really not knowing if the fish are looking up.
Absolutely! While for many anglers the Salmonfly hatch is more myth than legend, all it takes is one great day or even one good eat and I guarantee you’ll be hooked. The sight of a nice trout with its mouth wide open waiting for your fly to float in is one you won’t soon forget.
For more information on the Salmonfly hatch, where or when to fish it or what flies to use, please give us a call or stop in at either of our locations. We are always here to help.