In the mid-1990s, I started a yearly autumn pilgrimage to the McCloud River under the guidance of my longtime mentor, Jim Moloney, to fish the October Caddis hatch. Year after year, we descended upon the lower river below the McCloud Reservoir dam during the fall, learning the details of the life of North America’s largest caddisfly. Our crew of dedicated, seasoned anglers would set up base camp for a few days or weeks at the Ah-Di-Nah Campground until the closure of the regular trout season on my birthday, November 15. It was a tight-knit group, and we would work together to find insights about the nuances of October Caddis behavior, sharing those experiences every evening around the campfire. When the big bug of fall was hatching, nothing else really mattered.
The lower McCloud, though, is just one of the many streams where California fly fishers can chase this amazing autumn hatch. The October Caddis can be found in most Western freestone rivers, streams, and creeks. Northern California watersheds, in particular, are legendary for the hatch — not just the McCloud, but the upper Sacramento, the Pit, and the Truckee Rivers, as well as portions of Hat Creek, the Trinity River, all forks of the American River and its tributaries, the North, Middle, and South Forks of the Yuba River and its tributaries, the upper reaches of the Feather River system, including the West Branch, the South, Middle, and North Forks and their tributaries, the Mokulumne and Calaveras Rivers, the upper South San Joaquin River, and hundreds of lesser small streams across California. When it’s on, anglers go a little crazy for it, and so do the fish.
The Bug
Like all caddisflies, the October Caddis (genus Dicosmoecus) passes through three different life stages. The first is a cased larva, about 1.2 inches long, pale orange in color and plump when fully mature. During the early months of life, when the larvae are smaller, their protective cases are made from organic matter, neutrally buoyant materials such as leaves and small sticks that are easy to haul around, attached to a foundation of silk that they produce. As the larvae grow in size through the first spring and summer months, they abruptly switch to cases made of fine pebbles, which offer better protection from turbulent currents and also are easier to anchor to the bottom of the streambed. You can sometimes see these larvae crawling around, dragging their cases with them as they forage for algae and decaying plant and animal matter. Although primarily grazers, October Caddis larvae are omnivorous and capable of preying on other, smaller aquatic insects. In the late spring and summer, when they outgrow their existing cases, they may drift caseless before constructing a new one. This usually occurs around the latter part of the afternoon and makes them especially vulnerable and appealing to hungry trout. October Caddis larvae live for approximately two years before entering the next phase of their life cycle.
The second stage is the pupa. In mid to late summer of the second year of life, the October Caddis pupates, sealing up its case prior to the final metamorphosis into an adult. Cooler water temperatures in the late summer and fall trigger them do this in a synchronized way. This stage lasts nearly two months, and when pupation is complete, the October Caddis chews its way out of the case and emerges from the water by building up gas bubbles under its skin, which helps it to float near the surface, where it drifts, in some cases for long stretches, before finding shallow water and structure, where it finally crawls out. This emergence is likely to take place in water too shallow for trout to feed comfortably, but there are exceptions, when trout find enough depth next to the shoreline. I have also seen the emerging caddis rocket out of the water, hatching midstream in the middle sections and tailouts of major runs.
Throughout the spring and summer seasons, anglers may see empty October Caddis cases on top of rocks and assume they have hatched out there. What they are really seeing is what’s left of a water ouzel’s dinner. The small gray bird commonly known as the dipper eats the same aquatic insects that trout do. The dipper swims underwater and retrieves a cased caddis, brings it up to the top of a rock, and pulls out the larva. The water ouzel is the product of thousands of years of evolution within the river’s ecosystem, and I love watching them work the water and riffles. The last stage is the adult. The adult October Caddis has a burnt-orange body, grayish hairs around the base of its legs, and a large, tent-style overwing the color of pine bark that camouflages it from predation by birds such as the Steller’s jay while it rests in the conifers near the stream after emergence.
The adults are most active during the warmest time of the day and prefer exposed bends of the river that receive plenty of sunshine. Because they can eat and drink water, they live for months, until there is a hard freeze or snow. Some of the best days I’ve had when fishing the October Caddis hatch have been days with a light snowfall. The bugs fell from their perches among the conifers into the river or from streamside vegetation and were helplessly drifting down the foam lines into the mouths of hungry trout.
The October Caddis can mate several times during its short lifetime. When the female is ready to oviposit her eggs in the water, she bounces up and down above the stream, hitting the water and rising again. Each time she dips her abdomen onto the water, she releases eggs, which sink down to the bottom and hatch into larvae, completing the life cycle.
Tight-Line Nymphing
Early in the morning, before the adults are active, tight-line nymphing is by far the most effective way to fish the October Caddis hatch. Most of the rivers with strong October Caddis populations have pocket water, pools, and short runs that are well oxygenated, hold plenty of fish, and friendly to nymphing without an indicator. Anglers can get incredibly close to their quarry, with the bubbling and turbulent water surrounding them masking their presence. Being in direct contact with your flies is much simpler than constantly mending your fly line and worrying if your drift is drag free or if your indicator depth is set correctly. If you had to choose one style of presentation to catch fish consistently, day in and day out, this would be it.
For tight-line nymphing, I particularly like the Euro-nymph technique. Current Euro nymphing rods have two properties that set them apart from a standard fly rod: a soft and sensitive tip and a length of from 10 to 11.5 feet. The specialized tip allows you to feel every tick on the bottom substrate and also the slightest grab from a fish. To compensate, these rods also have a much stronger butt section a few weight sizes higher in order to facilitate fighting and landing larger trout. The longer length on the rods allows the angler to reach areas a shorter rod cannot and to achieve a better drift with more control. It also makes it possible to fish multiple pockets or areas of a run from one wading position. But the length requires a different mindset when using them. Be extra careful walking down trails and through brushy portals to the river. It’s easy to get the tip caught in a unsuspecting branch and snap it off. Also, because of the flexible tip, when you jiggle the rod while rigging, the leader will want to spin around the rod, creating an ugly tangle. It’s best not to hold the rod while rigging, if possible.
Setting up a rod for tight-line nymphing is fairly straightforward, though not as simple as it was in the 1970s, when my father taught me. The European influence has greatly changed the game, with specialized, small-diameter fly lines, sighter sections of line, tippet rings, swivels, and many other variations. Fly fishing is all about personal preferences, and tight-line leaders can be rigged many different ways. If you’ve had success using your own formula, you will fish it with confidence, so go with what works for you. I tend to experiment a lot with different lengths and materials in the construction of the leader. I like to test and evaluate and refine the connection to my flies. Here’s my current formula. I start with a competition nymphing fly line with a diameter of .022 to .024 inches and attach a 6-foot section of 12-pound-test mono using a Nail Knot. Next, I attach a 3-millimeter tippet ring, then a 2-foot multicolored sighter section with hanging tag ends from Blood Knots for better strike detection. Then I attach a 2-millimeter tippet ring, add 3 to 4 feet of 3X to 5X fluorocarbon tippet, then attach another 2-millimeter tippet ring. To the last tippet ring, I add 9 to 12 inches of 5X tippet, tie on a small fly (even as small as a size 22), then add another 12 to 14 inches of 5X tippet off the eye of the smaller fly and tie on a much heavier and larger fly. Sometimes I mix it up, though, with the heavier fly first, trailing the small fly for more movement in the current. This is what works for me.
When I’m fishing the October Caddis hatch, the larger fly is of course an October Caddis pattern. There are a whole lot of fly patterns out there that imitate the early life stages of the October Caddis and its emergence. My favorite is a much-modified version of Gary LaFontaine’s Sparkle Pupa. I eliminated the wing of deer hair and the encasement of Antron around the body.
October Caddis Sparkle Pupa
Hook: TMC 300, size 8 to 10; or, if Euronymphing, a jig-style TMC C450BL with a slotted 3.8 mm tungsten bead
Thread: Black 6/0 UNI-Thread
Weight: 10 to 15 wraps of .020 lead wire (optional black 4mm bead)
Body: Orange sparkle dubbing with added cinnamon UV Ice Dub
Ribbing: Medium gold wire
Feelers/legs: Mallard flank feather and fine brown ostrich herl
Head: Black ostrich herl
Weight is added to the fly, rather than to the tippet, to get the fly down. You can use a traditional slightly curved nymph hook with multiple wraps of lead, or a bead, or both. Apply slightly less weight if you intend on mainly swinging this pupa pattern. Conversely, for a true Euro-style fly, use the above-listed heavy-wire jig hook with a slotted tungsten bead. I wrap the body using Gary’s technique of touch dubbing for added translucency, which is the most important characteristic of this fly. After ribbing the body, pick out the dubbing evenly. Make the head on the large side and full with the black ostrich herl.
Enough how-to articles have been written about tight-line nymphing that I won’t go further into it here, but I believe there are three important elements that produce hookups. First, vary the depth at which you fish your flies with a series of casts, from the top of the water column down to the bottom. Not all fish are on the very bottom, and many will be suspended at different levels. Trout seldom look for food below their line of sight. While fishing a pocket, cover it all, from top to bottom, before changing position and moving upstream.
Second, lead your flies through the drift with the tip of the rod. In slower water, pull the flies through the drift with a natural drifting speed while leading with the tip of the rod. When there’s any movement of the sighter section or where the leader enters the water — an abrupt stop, a slight twitch — make a brisk hook set downstream and to the side of the river where you are standing. Hook sets should occur often through each drift and presentation.
Third, when your drift is done, allow the leader to swing in the current until it is fully extended downstream. This will mimic the technique of swinging a soft hackle, with the rise of the fly toward the water’s surface resulting in a trigger response from the trout. Seventy-five percent of the fish hooked this spring on the Middle Fork of the Feather River by my guests came at this point in the drift while tight-line nymphing.
Dry Fly Action
As the day warms, the adult October Caddis becomes an active flyer, patrolling the skies upstream and down and high above. If the hatch has been going on for a week or more, most of the trout will be looking up for them — for both females laying eggs and the clumsy males that fall off the streamside vegetation into the drink. Fishing an October Caddis dry-fly pattern on a size 8 hook can be a heart-pounding experience when a large trout sucks down your fly.
Rod selection, line choice, and rigging for fishing October Caddis dries are not complicated at all. A 9-foot to 10foot 5-weight rod with a relatively soft tip to protect tippets is a great choice. Match that with a weight-forward line and a 9-foot leader tapered to 4X on bright days and to 3X in the evening low-light conditions. These will turn over a big fly better than 5X, stand up better to abrasion from rocks and foliage, and you’ll have greater success pulling your fly out of misguided presentations that end up in the bushes.
Many anglers use a dropper nymph off a big dry fly to increase their odds, but in my opinion, you’re taking away from the true experience of fishing this incredible hatch. I’ve always used a single dry fly when fishing the October Caddis hatch. You can focus more on your presentation. My favorite dry-fly pattern is an October Caddis version of Nelson’s Caddis. I first saw a similar pattern in a book printed in the early 1960s titled Trout and Steelhead Flies of the Pacific Northwest. That fly did not feature a hackle, and the head of the fly resembled an Elk Hair Caddis’s. Today, most anglers know this fly as tied in the 1980s by Nelson Ishiyama, owner of the Henry’s Fork Lodge in Idaho.
Nelson’s Caddis
Hook: TMC 101 or TMC 100, size 8
Thread: Tan 6/0 UNI-Thread
Rib: Tying thread
Body: Orange Larva Lace stretchy closedcell foam
Wing: Dark elk hair, three to four stacks
Hackle: Premium furnace hackle, six turns
Start the Larva Lace body, tie in a wing stack, the wrap more Larva Lace ahead of it, and repeat until you reach the hackle tie-in point. Ribbing the foam with tying thread between wing stacks as you go helps keep the foam intact after being chewed on by toothy trout. Clip the hackle short and even on the bottom so the fly sits more flush in the surface.
There are two ways I like to present this fly on the surface. The first is short-lining pocket water, with the rod elevated, most of the leader off the water, and the angler as close as possible to the quarry without being detected, as in tight-line nymphing. I make an upstream cast at the top of a pocket on the seam of the fast and slow water that is closest to me, with only a half foot to two feet of the tippet on the water’s surface. With your fly presented this way, the trout are not spooked by a lot of leader and fly line on the water. I keep the rod elevated from the beginning to the end of the drift, but not too high to prevent setting the hook. Next, I’ll cover the outside seam. Hit all parts of the pocket — not just the seams, but also the area downstream of the boulder that created the pocket, and the pillow of water just above the boulder.
The key to success is to twitch the fly, imitating the behavior of the natural, even bringing it off the water a few inches or so and back down several times to imitate the behavior of an ovipositing female. If you’re just dead-drifting the fly and not animating it, you’re not triggering as many strikes as you could.
I use the second presentation when I need to make a longer drift in a run or large pool. It’s a downstream presentation using a reach cast and a bump feed to let out line so the fly drifts naturally to the fish and the fish doesn’t see your leader or fly line. Downstream presentations are a must when targeting selective feeders and always offer the greatest chance of fooling a fish. You can find a more thorough explanation on the technique in my “Fishing the Dry Fly: Two Ways to Improve Your Game” in the July/August 2017 issue of California Fly Fisher.
We are fortunate to have so many legendary hatches in Northern California on so many different waters: Green Drakes on the Truckee River, Skwala stoneflies on the Yuba, the Hexagenia hatch at Lake Almanor, and the famous spinner falls on the Fall River. The October Caddis hatch may be the best of them all, and nearly every major watershed throughout the north state has a thriving population. That’s a lot of water to cover. Crisp mornings, blazing fall colors, and big dry flies all welcome the autumn rhythms of the big bug.