Small Nymphs for Huge Results
by Danie Erasmus
European nymphing methods have received a lot of attention in North America over the last 15 years. These methods are very effective in catching fish and are innovative in overcoming the challenges of fishing small nymphs, which requires a lot more attention to how, when and where you fish. By adapting the best ideas of the European presentation techniques to matching the hatch, fishing with small nymphs becomes more practical and a realistic option in the toolbox. This article takes a North American angle, focused on matching the hatch, to European nymphing methods.
Most fly anglers tend to be over analytical and nit-pick – they want to know what size is exactly a 'small nymph'. To satisfy these obsessive-compulsive tendencies this article defines small nymphs as anything tied onto size 14 hooks and smaller. You could add another category of micro nymphs, which are tied onto size 18 and 20 hooks.
Before stepping into the water it is always a good idea to take a few minutes to see if any fish reveal themselves. The fish may either rise to hatching insects or you will see flashing from fish feeding on nymphs. A few summers ago I was doing this exact thing on a run, but the fish were hidden better than a special-forces team. As there was no clue from the fish, my approach was to cast a few different dry flies to some likely holding spots, followed by drowning a few larger stonefly nymph imitations. Usually this would have produced a few fish, or at the very least a few strikes, but I was still left empty handed. Then, on my third cast after switching to a size 16 clinger mayfly nymph, a 15-inch rainbow trout made a mistake. During the next few minutes a few more fish equal in stature fell for this nymph, and received a lip piercing.
Other than cherry picking specific situations to convince you of small nymph fishing, there are a number of good reasons to do so:
· The overwhelming majority of aquatic insects are small
· In highly fished systems small nymphs can be the key to success
· Mastering the art of small nymph fishing makes you a smarter angler
1. SMALL NYMPHS ARE ALWAYS ON THE MENU
Taking a kick net sample through a riffle shows that the vast majority of insect nymphs and larvae are small. Trout then see a lot more small nymphs than larger nymphs, and have to feed longer on those small nymphs to obtain the same amount of calories. Consequently, trout are conditioned to feed more often on small insects than larger insects.
Mayflies make up a major portion of the small nymphs trout feed upon and they become prey in a number of situations. Trout feed opportunistically on struggling nymphs that are swept downstream by fast flowing water. Mayfly nymphs also exhibit behavior where they let go of the river bottom on mass, drifting downstream. Called dispersal drifts, they are off to find new habitat and these migrations peak early morning and early evening, exposing them to predation. Nymphs are also susceptible when hatching as many species swim to the surface to hatch.
Mayfly nymphs occupy a wide variety of habitats and water types including riffles, runs, back eddies and pools. In streams mayfly nymphs have adapted to either cling or crawl among the rocks, or swim and dart from rock to rock in the fast current.
Clinger and crawler nymphs tend to occupy faster flowing water in riffles and runs. These nymphs are flat, stout and wide so that they can cling to and live among rocks without easily being swept away. Effective fly patterns imitating these nymphs should have the same wide and stout profile, and be heavily weighted. The stout, wide shape is very convenient for a fly tier as it allows for the inclusion of over-sized beads and lead wire to help these flies sink faster.
Swimmers, such as those belonging to the Beatidae family, inhabit both fast and slow moving water. Nymph imitations of these mayflies should be slender in appearance, which does not allow for a lot of weight to be added to the flies. Although, you could cheat a little bit and use oversized shiny bead heads with slim bodies or the very popular Perdigon nymph. To fish these flies effectively, focus on slower moving runs.
Caddisfly larvae are also a major component of small nymphs. Trout feed on caddis larvae regardless if they have a case, spin a net, or are free-living. Most caddisfly species' larvae also perform a behavioral drift throughout the season, making them an excellent, easily accessible food source for trout. Many caddis larvae also expose themselves when suspending mid-current using a silk thread that is attached to the substrate. Called rappelling, the larvae attach the silk thread to the substrate and then rappel downstream to new habitat.
The American grannom is one of the more important small caddis to consider as they inhabit moderately flowing runs in good numbers, and where it is practical to fish small nymphs. This case-building caddis' larvae are easily recognized by the four-sided chimney-shaped cases they build from small twigs. Grannoms cling to the topside of rocks and aquatic plants, and exhibit the rappelling behavior. It is quite common to find these larvae with their cases in a trout's stomach.
Small free-living and net-spinning caddis are also excellent fish food. Imitating predacious free-living caddis is more challenging as they occupy fast moving riffles, but since they are actively hunting their prey and moving around a lot, they are often washed downstream. Unable to swim very, well free-living caddis end up drifting long distances downstream. Net-spinning caddis setup their shelters and nets in more moderately flowing current, water suitable to fishing small nymphs. These larvae leave the safety of their shelters to find food, inadvertently exposing themselves to danger.
The overall the shape of caddis larvae permits the addition of a fair amount of weight when tying small imitations. Tungsten beads and lead wire along the shank of the hook is key in tying effective small caddis larvae.
Based on their physical size alone, this insect order falls squarely in the small nymph category. Among the midges, chironomids are the most important family when looked at with fishing goggles. More synonymous with still water fishing, chironomids are also relevant to stream fishing, but they are ignored by many anglers, mostly because they are small and thus hard to fish. With multiple generations hatching throughout the fishing season midges are always relevant, and since they continually spread downstream through dispersal drifts trout feed often on the bloodworm larvae. They are so abundant that even in freestone rivers you can see substantial numbers of chironomid larvae in riffles if you sample with a Surber sampler. It would be very challenging to fish chironomid imitations in riffles as the water is just too fast flowing. Water types such as large back eddys are good places to fish chironomid larvae and pupae imitations. In spring creeks and tail waters, chironomids are abundant and are a substantial part of a trout's diet, and a good winter-hatch to fish.
Compared to the size of flies that anglers usually fish in still waters, in streams chironomid larvae and pupae imitations are much smaller. You will seldom fish imitations larger than size sixteens. Tie your imitations with slim bodies and over-sized tungsten beads. In streams chironomid pupae imitations with dark coloured bodies and copper or silver beads are effective.
Stoneflies are more known for their large size but the majority are actually quite small. Usually the smaller stonefly species' nymphs are not that relevant to fishing as they emerge when fishing conditions are challenging. Small stoneflies emerge and peak in numbers during June and July when many rivers are high and fast flowing. There are a few circumstances though, when it is worthwhile to fish small stoneflies.
The small Perlodid genus Isoperla, also commonly known as the Little Yellow Stonefly or Stripetail, is an important small nymph to imitate. It occupies streams and rivers across the continent and is often found in high numbers. Although small, it is big enough to add sufficient weight to fish effectively. Nymph imitations of these yellow and brown coloured nymphs are tied onto size 14 hooks, and are fished from late June into July.
In winter, small black stoneflies of the Capniidae family, commonly known as Winter Stoneflies or Snowflies, hatch from February to April. As water levels are low and clear, small black nymph imitations tied onto size 16 hooks can be effective (for this time of year) when fished along the shoreline and in slower moving runs.
Tying effective small flies
Small nymphs are simple to tie and many patterns incorporate the most recent advances and ideas. In my opinion the most important attributes of effective small nymphs are their overall silhouette, colour and sink rate. Nymphs today are tied with these attributes in mind, but with features that attract fish. These features include fire orange or pink hotspots and tags, brightly coloured tungsten beads, and shiny flashback – all materials that help get a second look from an educated or skeptical fish.
When designing effective nymphs use materials for the body that provide the best hydrodynamic surface and shape. Avoid furry and fuzzy looking small nymphs as they trap air reducing their sink rates. Instead tie flies with bodies that are slim and smooth. Tie simple bodies from either thread or copper wire, especially the latter as it helps getting the small nymphs down. Instead of regular brass beads use oversized tungsten beads to get the flies to sink faster.
2. SMALL NYMPHS ARE FOR HIGH-PRESSURE SITUATIONS
On heavily fished waters trout learn to avoid flies pretty quickly. The majority of these flies are usually large nymphs. If you do not develop the skills to fish small nymphs you put yourself at a disadvantage.
This past season I was fishing a well-known and very popular stream. As I approached a section of water that sees flies daily I knew I had my work cut out for me. This piece of water had a riffle transitioning into a run with a slight bend. This bend created an obvious seam between the faster moving water in the main current and slow moving water on the inside. After staring at the water for a while it was clear that nymphing was the best approach. As it was June, I knew that large salmonflies were still on the menu and I could fool a few fish with low IQs to take my nymph. Working my way through the riffle and main run I had one fish on briefly, and that was it – but I knew there had to be a few more fish.
My Plan B included changing my leader and fly to a long French leader type setup and a #14 Stripetail nymph. Stepping out of the river and taking a wide birth to the lower end of the run, I cast upstream into the shallow slower moving water right next to the seam. Like a typical fishing story, except this is true, on the first cast my hi-vis mono sighter slowed down. I lifted my rod tip and a beautiful rainbow launched itself out of the water. With a “What the …” I manage to overcome my own adrenaline rush and land a 14-inch rainbow who had no shortage of the fight-or-flight hormone. The same approach produced a few more fish in the next hour.
Most anglers tend to fish larger nymphs, and in heavily fished systems trout quickly learn to avoid the large nymphs. To anthropomorphize the fish develop an association between the large flies and a bad experience. This is exacerbated by the fact that the majority of the real food is actually small and not large. In situations like these fishing large fake nymphs is putting the angler at a disadvantage.
3. FISHING SMALLER MAKES YOU A SMARTER ANGLER
The big challenge in fishing small nymphs is getting the fly down to the fish. To be effective at doing this, take the time and have the patience to develop the knowledge and understanding of contemporary methods, terminal tackle, and tying materials. Half the fun is playing around with all the new ideas and inventions.
Tools of nymphing
Fish take small nymphs very subtly, often just inhaling them, which is almost undetectable sometimes. The use of a strike indicator is essential, but choosing its design can make or break your nymphing. Strike indicators come in two types: floating indicators that suspend flies, and sighters that only indicate a fish's strike. When small nymph fishing, floating strike indicators can be problematic as surface currents are faster than currents near the riverbed. A faster moving strike indicator can drag nymphs out of the strike zone, and with small nymphs this is exacerbated. Sighters such as brightly bi-coloured (High-Vis) monofilament that are either coiled (Curly Q/slinky), or straight are excellent as they cause minimal drag, and assist in detecting strikes.
A third option is indicator putty, and it can be used as both a floater and sighter, and be molded into different shapes and sizes. To use it, simply take a small amount of the putty and put it on the leader as a sighter, or mold it into a very small egg-shaped ball to suspend small nymphs in slower moving water. Indicator putty is easy to cast and since you can make it quite small, drag on the surface is reduced quite a bit.
Split shot is very effective in pulling flies down to the fish. The most common practice is to attach split shot above the flies, which is a mistake with small nymphs. When a fish grabs the fly it pulls against the heavy split shot, dampening the signal of subtle bites. In slower moving water fish feels the resistance from the split shot before the angler sees the strike. The fish end up rejecting the nymph faster than the angler can react to it, that is if the angler actually sees the bite. In the end anglers see fewer strikes and usually only see the aggressive strikes. Personally I try to avoid the use of split shot and try to include as much weight as practically possible in the nymph itself. With the weight in the fly the angler has direct contact with the nymphs, which helps with seeing strikes.
Alternatively, tie on a tungsten bead with a non-slip loop knot as a point 'fly' and your small nymphs as droppers. With different sizes of tungsten beads the sink rate can be regulated and the angler is in contact with the flies as the weight is below the flies.
Where do you fish small nymphs?
As a stream flows the main current transitions between the major types of water such as riffles, runs and pools. There is also what I refer to as minor types of water that are formed by water not part of the main current, but are still areas where you will find fish, such as riffly-runs. Many anglers do not recognize a riffly-run and dismiss it as merely shallow water, and wade right into one to fish the main water.
Riffly-runs are around knee deep with the surface of the water, not flat like a run but they have the appearance of a riffle. And yet the surface is not as broken up or as fast flowing as a typical riffle. The flow rate of the water and gradient of riffly-runs resemble a run more closely than a riffle, making riffly-runs exceptional water for small nymph fishing. This minor water is also good habitat for the mayflies, caddisflies and stoneflies mentioned earlier. Rainbow trout and the western North American species mountain whitefish love feeding on nymphs in riffly-runs.
How do you fish small nymphs?
There are many established nymphing methods and of these French nymphing is made for small nymph fishing in low and clear water. This method employs extra long leaders of 20-feet or longer to present small flies to picky fish. Using a tapered leader to cast the small flies with no fly line out the tip, and a Curly Q sighter, the angler can detect those subtle strikes. Casting upstream and slightly across the current, the rod tip is lifted to keep the Curly Q just above the water while maintaining contact with the flies. A fish's strike is detected when the coils of the sighter are being pulled apart.
To many, the French nymphing method can be intimidating as casting 20-foot plus leaders without fly line is scary. There are other ways to present small nymphs as well. The key is in your leader design, and where and how you fish your nymphing rig.
If you plan on designing your own small nymph fishing leaders keep in mind that an effective leader is longer than usual, and is tied with segments of level tippet that is small in diameter. Long small diameter level leaders allow small nymphs to sink faster than tapered leaders. Use a leader that is two, three or even four times longer than what you would normally fish. For example when fishing in two- to three-feet of water build a leader consisting of four feet of eight pound Maxima Chameleon that transitions to two feet high-vis monofilament and then another four to six feet of 5x or smaller diameter fluorocarbon tippet. With each transition point connect the sections with tippet rings. This leader setup work well for water like riffly-runs, runs and pools.
With 10 to 15 feet of fly line out the tip of the rod cast upstream at a 45-degree angle and then lift the rod tip to keep as much fly line of the water. With this approach fly rods that are 10 to 11 feet in length are very helpful as you can keep line easier of the water.
Small nymph fishing may not be for everyone, and fishing small nymphs is not going to turn you into a nymphing superstar. There is definitely a learning curve to this approach and it will take some time to refine your skills, but the process of mastering small nymph fishing is half the fun and in the end it adds to your arsenal. Fishing small nymphs requires that you fish smarter, not harder.
First published in Spring 2018