Crane Flies, Damselflies, and Mice
June 29, 2017
I will never forget the fall day I witnessed one of the largest BWO hatches I've ever seen on the infamous South Platte. There was a large pod of browns holding at the head of a long run where the riffled water poured into a deep plunge pool. The fish were being extremely selective as they lifted gently to sip in the mayflies sailboating on the surface.
After I'd changed my client's flies for what felt like the millionth time, a light bulb went off. "We have to change this up," I decided. "Let's try something completely different to see if one of these fish will pounce on it." The first presentation was magic, and my client's jaw dropped as the largest fish, previously an occasional sipper, hunted down and smashed a swimming #10 Morrish Mouse.
I first gained confidence throwing big stand-out meals on the surface the year before when I was guiding on the Naknek River and the surrounding fisheries in Katmai National Park. While preparing my fly boxes for the season that largely consisted of painted beads, Flesh Flies, and big nymphs, fellow guide Matt Bynum told me, "The topwater scene up here can be incredible. Don't be afraid to throw a mouse to stand out to these fish."
I put this method to the test on my first guide trip. After jetting up and drifting down one of the side channels, I noticed some nice 'bows prowling the soft seam at the point of the island. We landed some of the smaller fish using beads to imitate salmon eggs, but I wanted to see if a mouse might attract the attention of one of the giants. Sure enough, one of those tanks poked its nose just out of the water, flared its gills, and delicately "sipped" the mouse from the surface. Ten minutes later my client slid the submarine into the net, and I had my introduction to alternative food sources. It is easy to get stuck in the mindset that downsizing will fool more trout because we know this is the safest way to have your imitation live up to the definition of "imitate," however, sometimes it is better to be a contrarian.
Large trout can be lazy by nature and resist spending excess energy to feed. This is why some targets can be reluctant to take small bugs on the surface, but lose their minds when they have the opportunity to hunt and destroy one big monumental meal that catches their eye.
I've found that crane flies, damselflies, and mice all stand out in a crowd because these meals supply the fish with the maximum amount of nutrition for the smallest amount of effort, and trout everywhere are familiar with them. One thing these three value meals have in common is that they disrupt a lot of water on the surface when they ride, leaving a V wake that demands investigation.
On one hot summer morning, I heard occasional explosions on the surface that led me to believe something was not just eaten, it was being destroyed. As the day pushed into early afternoon, I was standing on the edge of a long riffle delivering small flies to subtle eaters near the opposite bank. The afternoon was calm and quiet, with only the occasional sound of a trout sucking in spent Tricos.
I heard a buzzing sound and watched as a large adult crane fly skipped across the surface of the water tumbleweed-style. A big trout gave chase, missed the crane fly, swung around, and came up from underneath it like Jaws for the second and final attack.
Also known as mosquito hawks, these long-leg insects are found in freshwater ecosystems worldwide. Including the extremely gangly legs, the adults can reach the size of silver dollars. Many fly fishers use subsurface imitations of crane fly larvae, but very few of us take advantage of the adults, which can be clumsy fliers.
The key to imitating what looks like an oversized mosquito is the legs. Imitations like the Daddy Long Legs Crane Fly (#8-10) match the body profile with a generous amount of hackle and leg materials to lift the fly high on the surface so it can roll, matching the movements of the naturals.
These "paired-winged" flyers are in the same family as dragonflies, and are predators that become prey as they hunt for other adult insects on the river edges or stillwater shorelines. Male damselflies exhibit a vivid blue body compared to the pale olive markings of females. They hunt smaller insects near the surface of the water on warm summer days, and trout in most circumstances do not miss the opportunity when one of these meal tickets crashes onto the water.
Sometimes trout don't even wait for contact, and leap from the water to consume damselflies in midair. If you want to see beautiful and dramatic slow-motion video of this, I suggest you watch the short film Damsels in Distress at flyfisherman.com/damsels. A glimpse at this video makes it joyfully obvious how much trout enjoy feasting on damselflies.
I have always admired the beauty of these insects as they prowl the water, and at the first sight of any damselfly activity I quickly switch to a size 6 or 8 Parachute Damsel Adult.
It matches the long slender body of an adult, uses foam for buoyancy, and has paired Krystal Flash wings sticking straight out to the sides preventing the fly from rolling over. When complete, it looks like a small version of a Mountain Banshee from the movie Avatar.
One of my favorite times to throw the electric blue, black, and blue imitation is in between major mayfly hatches. For example, as the morning Trico hatch dies down and before the afternoon stonefly or mayfly hatch begins, trout are still eager to pounce on the next topwater meal. Concentrate on edges and shorelines, or the very spots where you might have struggled with selective trout during the hatch—there is a good chance those fish will react to your damselfly imitation.
Mice & Voles
As the name indicates, "fly" fishers have been historically focused on matching hatches of aquatic insects, but I have found many large fish that prefer to hunt and destroy furry mammals.
Meadow mice (also called field mice or voles in Europe) love fertile river valleys with lots of grass or tundra, as the vegetation provides protection from predators, and ample food. Mice are excellent burrowers, and frequently nocturnal, so you don't often see them. Like most things in nature, local mouse populations are cyclical, and the trout really get turned onto mice during periods of local abundance. In New Zealand, there are "mouse years" in certain forested areas that are related to the abundance of seeds from southern beech trees.
In 2012 there was an explosion in the population of montane voles along Silver Creek, Idaho that was known only to a few observant big-trout hunters who noticed unusual numbers of hawks, owls, coyotes, and rattlesnakes patrolling the riverbanks. These boom-and-bust cycles and periodic rodent migrations happen all the time on most North American rivers, yet fly fishers rarely recognize them. It's a well-known fact that hopper fishing can be excellent when adjacent hayfields are swathed, but not many of us realize how the local rodent population also reacts when a hayfield is cut.
The key to a mouse fly is the body design, extending legs, and a supple tail that S-curves like a snake when the imitation moves. In Alaska I learned to love imitations like a size 6 or 8 Mr. Hanky or a Morrish Mouse.
You can present these flies dead or alive. A live mouse dog-paddles across the current, kicking its legs and causing a wake in an attempt to reach dry land. Swing your fly on a tight line to match this movement, and add occasional extra twitches. If the extra movement does not attract attention, try a simple dead drift to mimic a mouse that has given up swimming and is along for the ride. Once you find the right delivery, hold on. You could be in for one hell of a fight.
When to Throw Down
Clear water provides the fish a better visual of the prey and commotion it is causing on the surface. These are surface flies with surface presentations, and you want as many fish as possible to see your flies.
Keep in mind that trout are wary creatures, they don't like to be seen by their prey or by larger predators, so low light provides the best bite. The challenge in low light—an hour after sunrise, two hours before sunset, or any dark and overcast day—is glare. The reflection of the sky, clouds, and changing color can make it impossible to see below the surface. On the other hand it can silhouette your surface fly, allowing you to track a dark, drifting object, or follow the disturbed water as it skates. I also believe low-angle light helps the trout see and track your fly better. No one likes staring into bright sun, and trout don't have eyelids or pupils that can contract.
When rigging these large flies, I tie on a single fly using 3X tippet to prevent potential tangles, and encourage a proper presentation. Attach the fly using a no-slip mono loop knot, and the fly will move more naturally on the surface.
Large drys create wind resistance, and are easier to cast on heavier weight-forward lines such as Scientific Anglers MPX. Finally, fly maintenance can help produce the long drifts you need in some cases to produce fish. If the fly begins to sink, I first pinch-dry the fly using a shammy, amadou patch, or Wonder Cloth. Then I use a desiccant like Shimazaki Dry-Shake. It is not uncommon for me to go through a whole container of Shimazaki every two or three days.
Statue of Liberty
Crane flies, damselflies, and mice disrupt a lot of water at the surface because of their mass and movement, and the best way to fish them is to make them move across the surface of the water. I cast across and slightly upstream, starting the drift with my rod tip just above the surface.
As the fly begins to drift and swim downstream, elevate your arm with smooth acceleration toward 12 o'clock using your hand and wrist to add twitching movements to the fly as it drags across the surface on a tight line. At the end of the drift, your arm should be raised well above your head, which is why I call this technique the Statue of Liberty.
This technique helps keep the fly at the surface instead of dragging it under, and keeps you in constant contact with the fly. If a fish strikes at the end of the cast when your arm is vertical, sweep the rod to the side to set the hook. This helps position the fly in the corner or roof of the fish's mouth, and works well with all three of the fly patterns described here.
Use angles to your advantage with this skating method. If you cast upstream at a 45-degree angle you can add a short dead-drift at the start of your cast before the swinging and skating begins. If you cast more downstream, it keeps you out of view, and tension quickly swings the fly to the target's position below you. Incidentally, the Statue of Liberty was the technique my wife Michelle used to land her personal best trout, shown on the cover of this issue of Fly Fisherman.
"The rise of a trout is far from being the only thing that matters about fly fishing, but it is for many of us the most exciting thing." This is one of my favorite quotes from Paul Schullery in his book The Rise. The thrill of fooling a nosing fish is hard to beat, but when that doesn't work, you can still catch fish on the surface by standing out in a crowd with these underused, and thrilling big-fly alternatives.
Landon Mayer is a Colorado-based guide and author of several books including 101 Trout Tips: A Guide's Secrets, Tactics, and Techniques (Stackpole Books, Headwater Books, 2015).