Throughout the year, but especially during the spring and fall, small blackish and iridescent beetles of different sizes are found in trout stomach samples, even if the bulk of the food mass in the gut is predominantly another type of aquatic insect. Though trout may feed heavily on Callibaetis nymphs, damselfly nymphs, or midges, they will opportunistically take an occasional beetle or water boatman, should it lie in their cruising and feeding lanes. When beetles are mating, there also may be actual beetle “hatches” that trout key on and that can be fished.
Some years ago, I was a guest at the Sand Hill Lakes outside of Reno, a private pay-for-play venue on the diagonal route to Pyramid Lake. I was doing a magazine piece on private still waters. It turned out that another client, John Fukumoto, had booked that day on these three small spring-fed lakes so his grandson could work on his casting and landing techniques for larger fish, so instead of horning in on the limited amount of water, I elected to pull up a chair and chat with the fly-fishing guide who had brought the young man and his grandfather — Doug Ouellette, of Calvada Fly Fishing out of Reno. Doug and I opened up our fly boxes at lakeside, and I enjoyed a most interesting conversation about stillwater fly patterns.
Doug’s boxes contained iridescent aquatic beetle patterns that were works of art. The beetles, with their magenta, candy apple red, purple, green, and black reflective shellbacks, were unlike anything I had seen. He generously gave me four of the beetles, which included flies in charcoal, light orange, light olive and other surprising hues.
It also turned out that the youngster’s grandfather tied and was known for the colorful and effective beetle patterns that were in Doug’s box. Six months later, I was speaking at the Mission Peak Fly anglers in Fremont, and John Fukumoto surprised me with a box of his flies. He was grateful that Doug and I had elected not to fish and steal the thunder of an excited young man who was into his first really large trout.
I eventually researched beetles and water boatmen and started thinking about them more when I was on the water. Boatmen are sometimes known as “water crickets,” because they rub their appendages to make a chirping sound that is audible to humans under optimal conditions. But more formally, water boatmen fall into the taxonomic order Hempitera, family Corixidae, and aquatic beetles belong to the larger order Coleoptera, family Dytiscidae. However, both orders are often lumped together by scientists and nonscientists. This larger group has approximately four hundred thousand recognized species, one-third of all insect species in the world. In their aquatic form they lack gills, breathing through spiracle tubes on their backs and sometimes sides. These beetles can breathe on the surface, but carry air bubbles, enhanced by fine hairs on their bodies and legs, that give them a halolike sheen when seen in the right light. The bubbles allow them to go underwater for periods of up to half an hour.
They move vertically up and down in the water column, mostly in depths of less than 10 feet on the edges of lakes, ponds, marshy areas, and in slow-moving waters. Their bodies are armored for protection from predators or physical injury and are hydrodynamically efficient. They are superb swimmers and can also fly in order to find new habitat or mate, and have a life cycle somewhat similar to better-known caddisflies in that they have an egg stage, a larval stage with three molts, a pupal stage, and an adult form. They have strong, broad mandibles (jaws) for tearing, and some can inject a paralyzing venom through slots in these jaws to incapacitate their prey. They range from 3 to 45 millimeters in length and occupy diverse habitats. Some eat algae, plant material, and detritus, while others are predacious and eat tadpoles, crustaceans, small fish, mosquito larvae, other insects and scavenge on carrion.
So how do we capture fish using fly patterns that mimic these insects? Beetles can become fish food when they are blown onto the water from riparian areas and, in their aquatic form, when they are captured by grazing fish rooting among aquatic vegetation. They are also vulnerable when they move up and down in the water column for surface air and during mating, when they rise to the surface to rest, dry, and then pop up into the air, flying to where eggs will be fertilized. After mating, females return to the water and seek plant stems on which to lay their fertilized eggs. This phenomenon occurs during the spring and early summer as inshore water temperatures rise. Eggs hatch in 7 to 14 days, depending on water temperatures, then morph into larvae that eat much the same food as the adults. Similar life cycles are exhibited by the aquatic beetles.
In higher-altitude lakes, especially in ones above 7,000 feet, I cast a water boatman or a black beetle pattern to sighted fish with high expectations of success. The presence of aquatic vegetation can be an important key. I have fished Quail Lake, with its beautiful lily pads, as well as Sawmill, Watson, and Spooner Lakes and Indian Creek using boatmen and beetle patterns. Some of the most enjoyable fishing that I’ve experienced has been at Sawmill Lake, casting to cruising fish that may be a foot or two underneath the surface.
As with most sight fishing in lakes, you need to cast out a ways from your float tube, pram, pontoon, or boat. Rarely will a fish take a fly in closer than 35 feet. See my “Can Fish Think?” in the September/October 2016 California Fly Fisher. And as with most sight fishing, you have to guess which way the fish is headed and lead it. This kind of angling can test your nerves. I’ve seen huge trout swim up to a boatman pattern that is slowly sinking and circle the fly as many as two times, then suddenly rush in aggressively and take the fly. Once they’re comfortable with their choice of prey, they act as if they know these bits of food are tasty and don’t want them to escape. This works sometimes in open water, but is more often successful when fishing shoals or in inshore areas where boatmen are likely to be found.
If you don’t have a fish to key on for casting a boatman pattern, try fishing a boatman pattern blind. Use a floating line with long leaders in the 12-to-14-foot range that go down to a 5X tippet. Give the fly time to sink, then make short jerks with pauses in between, since the beetles rise and fall erratically. Boatmen can ride an air bubble to the surface or row with their efficient paddlelike legs, often doing one, then the other.
Another trick is to use small foam pinch-on indicators the size of aspirin pills and hang the insect imitation several feet underneath. These indicators cast easily and work equally well with small San Juan Worms and chironomid imitations. A slight ripple on the water is great, because it will bounce and dance the fly as well as make you less visible. A gentle wind is your friend. Make short, 6-to-12inch slow pulls with pauses in between, as when fishing chironomid patterns. This will make your fly rise in the water column, then fall. Also use this technique with damselfly nymphs whose sinusoidal movement is hard to imitate. Stealth is important in these situations.
I tie boatman patterns on light-wire scud-type hooks, and also on heavier wire hooks with a few twists of lead added. That way, you can cover more of the water column, as needed. You can tell which is which by the “click” or “clank” when you drop it onto a fly box lid.
In ultimate fly-fishing experience is to find mating flights of water boatmen. They can provide explosive fishing, but such flights don’t happen very often on most of the waters I fish. One such occurrence was in a large cove with a narrow entrance between Mosquito Slough and the mouth of Freeman Creek at Davis Lake. It’s been dry over most of the recent drought, but during years of normal precipitation it is quite shallow and perfect boatman habitat.
You can also try fishing the water boatmen pattern or one of many iridescent beetles as a trailer in a classic tandem with a fly such as a Woolly Bugger using a clear or camo intermediate line. I tie the dropper off the larger fly’s hook bend. Others swear by tying it to the eye of the first fly. Don’t be afraid of changing color if things aren’t working. The change in fish interest can be like flipping a light switch on. Also experiment with the first fly, going up and down in size and varying its color and retrieve.
Another excellent generic trailer that may imitate a beetle of some type is the late Don Stahl’s Pine Creek Special. It has a greenish, iridescent peacock herl body, brown hackle, and a white metal bead or glass head. The tail is two strands of amber Krystal Flash.
Whether dragging the tandem fly rig behind a pram, a float tube, or even a boat, it is advantageous to stop rowing or kicking periodically and let the fly line and rig settle into deeper water, especially near a ledge or drop-off. Be patient, and let the rig get deep. Hits will come as you start moving again and your flies rise in the water column.
Water Boatman
Some 15 or so years ago, I was given a simple water boatman pattern tied by an angling partner, Greg Betz, for a Tri-Valley Fly Fishers club trip to Five Dot Reservoir outside Susanville. The pattern, which proved to be quite successful, taught me a lot about this important item in a trout’s food chain.
Materials
Hook: TMC 2457, size 14 or 16, or TMC 2499, for a larger gap
Thread: Black
Shellback: Iridescent green Flashabou or other flat, Mylar-like synthetic tied in a hank.
Weight: .015-inch lead wire, if desired
Body: Iridescent green or bronze peacock herl.
Legs: Gray/black jig rubber or variegated Sili Legs
Tying Instructions
Step 1: Secure the hook in the vise and tie in a hank of Flashabou or Krystal
Flash where the shank starts to bend. Several trials will tell you how many strands are needed to make a broad shellback that doesn’t pull the legs down from the horizontal.
Step 2: Add 6 to 10 wraps of small-diameter lead wire to the hook shank, depending on the size of the hook, if weight is desired.
Step 3: Tie in two strands of peacock herl just forward of the secured Flashabou hank. Tie in a single set of legs perpendicular to the hook shank and one-third of the way back from the hook eye. You can leave them longer for tying ease and trim them to proper proportions later.
Step 4: Wrap one peacock herl forward and beyond the legs to just behind the eye. Overwrap the second herl forward and secure it. Use a third herl strand if it’s a bigger fly or if your herl isn’t bushy. Leave enough room to tie down the tightly pulled hank of Flashabou and to trim it short of the hook eye.
Step 5: Build a bulky head with black tying thread and apply a glossy cement. Trim the legs. If desired, you can also add Flexament, Loon Fly Finish, Hard as Nails, or thin Clear Cure Goo to the shellback to make it stronger and more reflective. After a little trial and error to get your proportions down, this is an easy fly to tie.
This pattern functions both as an imitator and as an attractor and is an addition to your stillwater fly box that gives you another option while fly fishing lakes and slow-moving waters. Stillwater environments are so complex that you never know what you may encounter.
— Trent Pridemore
