Euphausiid and Krill Patterns: How to Tie the Winter Flies That Puget Sound Cutthroat Can't Refuse

Winter on Puget Sound is the season that separates the dedicated sea-run cutthroat angler from the casual one. The chum fry haven't outmigrated yet (that's March). The sand lance schools won't concentrate along the beaches until May. The Clousers and Miyawaki Poppers that work all summer are sitting in the box gathering dust. And the cutthroat are still out there, cruising the nearshore zone in water as cold as 45°F, feeding on something.

That something is euphausiids, tiny, translucent crustaceans in the krill family (Euphausia pacifica and related species) that swarm in the Puget Sound water column year-round but become the dominant food source for sea-run cutthroat from November through February. Euphausiids are small (half an inch to an inch), pink-to-translucent, and weak swimmers, they drift in the current and get pushed by tides and wind rather than swimming actively. Cutthroat eat them by cruising through concentrations and picking them off one at a time, often just below the surface in slow, deliberate feeding patterns that look nothing like the aggressive slashing they do on baitfish.

The fishing is subtle. The flies are small. The retrieve is slow. And the rewards are significant, winter euphausiid fishing produces some of the biggest sea-run cutthroat of the year, because the fish that stay in the salt through winter are the largest, most experienced adults in the population.

What Euphausiids Are

Euphausiids (krill) are shrimp-like crustaceans in the order Euphausiacea. They're the base of the marine food web, the same organisms that feed baleen whales in the open ocean. In Puget Sound, smaller species concentrate in the nearshore zone, forming dense swarms that cutthroat, resident coho, and other predators feed on.

The natural euphausiid is:

• Tiny, 10-25mm (half inch to an inch)
• Translucent, the body is nearly see-through, with a pinkish or orange tint from internal pigments
• Weak swimming, they drift and pulse rather than darting like baitfish
• Schooling, they form dense concentrations that can be visible as pinkish clouds in the water

The fly that imitates a euphausiid needs to be: small (#8-12), translucent (materials that let light through), pink/orange/tan, and fished slowly (matching the natural's weak swimming motion).

The Patterns

The Glo Euphausiid

The Glo Euphausiid, popularized by Seattle's fly shops, is the standard Puget Sound winter krill pattern. It uses UV-reactive dubbing and soft partridge hackle to create a small, translucent, buggy fly that glows subtly in the low winter light.

How to tie it:

Step 1: Mount small bead chain eyes on the underside of the shank, the fly rides hook-up and the light weight keeps it in the top 2-3 feet without sinking to the bottom.

Step 2: Tie in a few ringneck rump fibers at the bend as a short tail, just long enough to suggest the euphausiid's tail fan. Add 2-3 strands of pearl Krystal Flash.

Step 3: Dub a thin body of UV Shrimp Pink Ice Dub forward to behind the eyes. The key word is thin, euphausiids are translucent, and a fat dubbing body looks like a scud, not a krill. You should see the hook shank through the dubbing.

Step 4: Tie in a natural partridge feather by the tip and take 1-2 wraps. Stroke the fibers rearward so they sweep back along the body, these suggest the euphausiid's swimming legs. Whip finish.

The Pacific Krill

A slightly different approach using EP Shrimp Dub brushes for a more three-dimensional body:

The EP brush construction creates a translucent, 3D body that mimics the krill's segmented appearance. Wrap the brush forward, trim to shape, add eyes, coat with thin UV resin. The resin adds a glassy translucence that catches light the way a real euphausiid's exoskeleton does.

The Killa Krilla

A simple, fast-tie variant designed for production tying, when you need a dozen krill patterns for a winter season:

The Killa Krilla ties in 2-3 minutes and is designed to be lost on the rocky Puget Sound bottom without regret.

Where to Fish Them

• Puget Sound Beaches, Every beach in our Puget Sound guide is euphausiid water in winter. Lincoln Park, Titlow, Dash Point, south Sound oyster beaches. The south Sound (below the Tacoma Narrows) tends to fish best in winter because the water is calmer and warmer.

• Hood Canal, Hood Canal's enclosed waters concentrate euphausiid swarms, and the cutthroat that winter in the canal feed on them heavily.

• Olympic Peninsula estuaries, Where OP rivers meet the salt, winter cutthroat stage in the estuaries feeding on krill before moving upstream to spawn.

How to Fish Them, Slow and Subtle

Euphausiid fishing is the opposite of Clouser fishing. Where baitfish patterns demand fast, aggressive strips, euphausiid patterns demand slow, minimal movement that matches the natural's weak swimming.

Line: Floating or intermediate. The euphausiids are in the top 2-3 feet of water. An intermediate line sinking at 1-1.5 inches per second keeps your fly in the zone without getting too deep.

Retrieve: Long, slow strips of 6-12 inches with 3-5 second pauses. Or the hand-twist retrieve, a continuous, almost imperceptible gathering of line that moves the fly at a walking pace. The hand-twist is the classic euphausiid retrieve because it perfectly mimics the krill's sluggish drift.

The take: Winter cutthroat eating euphausiids don't explode on the fly. They inhale it, a subtle tightening of the line, a gentle pull, almost indistinguishable from the fly bumping a piece of kelp. If you feel anything different from the normal drift, strip-set. Many winter euphausiid takes are detected only by the line stopping when it shouldn't.

Depth control matters. Euphausiids concentrate at specific depths depending on light and tide. On overcast days, they may be right at the surface, cutthroat will dimple the surface sipping krill like trout sipping midges. On bright days, they push slightly deeper (2-4 feet). Adjust your line and countdown accordingly.

Find the swarms. Euphausiid concentrations are sometimes visible as pinkish clouds in the water, especially in the south Sound's calmer bays. Birds working the surface, gulls picking at the water without diving, can indicate a krill swarm just below the surface. Cutthroat will be nearby.

When to Fish Them

• November–February: The prime euphausiid window. Baitfish have dispersed to deeper water. The cutthroat that remain in the shallows are feeding on krill. This is when the euphausiid pattern is the first fly out of the box.

• March–April: The chum fry outmigration begins and cutthroat shift to fry patterns. Euphausiids are still present but the cutthroat now have a preferred food source. Switch to chum fry near creek mouths, keep the euphausiid for beaches without creek inflows.

• Year-round backup: Even in summer, when sand lance and baitfish dominate, a euphausiid pattern is the change-of-pace fly that produces when nothing else is working. Some days the cutthroat just want something small and subtle.

The Seasonal Puget Sound Fly Box, Complete

With the euphausiid pattern, the Puget Sound seasonal fly box is now complete:

The euphausiid fills the November–February gap that was missing. The Puget Sound cutthroat angler now has a pattern for every month of the year.

How to Tie Them, Video Tutorials

Glo Euphausiid: Glo Euphausiid tying tutorial, The standard Puget Sound winter pattern, step by step.

Pacific Krill: Pacific Krill fly pattern tutorial, EP Shrimp Dub brush construction for a 3D krill body.

Killa Krilla: Killa Krilla tying tutorial, The fast-tie production version for winter coho and cutthroat.

Tips From the Vise

Translucence is everything. A fat, opaque fly that looks like a scud is not a euphausiid. The dubbing should be sparse enough to see the hook through it. The whole fly should be wispy, delicate, and nearly see-through. Hold it up to a light, if you can't see light through the body, it's overdressed.

Pink, not red. The natural euphausiid has a subtle pinkish tint from astaxanthin (the same pigment that makes salmon flesh pink). Your fly should be pink, peach, or pale orange, not fire-engine red. UV Shrimp Pink Ice Dub is the standard because it matches this subtle natural coloring.

Small matters. Most anglers tie euphausiid patterns too large. The natural is half an inch to an inch. Your fly should be 15-20mm total, a #10 or #12 hook with minimal materials extending past the bend. Size #8 is the maximum; #10-12 is better.

Bead chain, not dumbbells. The euphausiid pattern needs just enough weight to break the surface film, not sink to the bottom. Small bead chain eyes are perfect. Dumbbell eyes make the fly sink too fast and fish too deep, the krill are in the top 2-3 feet.

Build Your Box

• Glo Euphausiid #8 (6), the standard, bead chain
• Glo Euphausiid #10 (6), smaller, for picky fish
• Pacific Krill #8 (4), EP brush version, more 3D
• Killa Krilla #10 (4), fast-tie backup

That's 20 flies, enough for an entire winter season. The euphausiid patterns tie in 3-5 minutes each and use materials you probably already have (Ice Dub, partridge, Krystal Flash, bead chain). Tie a batch in October and you're set when the first winter cutthroat start sipping krill in November.