Dry-Dropper Rig for Trout

A buoyant dry, a short nymph under it, and how to fish the rig without a tangle.

From the book Fly Fishing for Nerds — $9.74 →

A dry-dropper is a dry fly with a nymph hung a short way under it. The dry is the fly you watch. The nymph is there for the fish that will not come all the way up. A hopper-dropper is the same rig when the dry is a hopper, or a foam fly standing in for one. This page is when to fish it, what to tie, and how to throw it so the two flies stay apart.

1. When a dry-dropper beats the other rigs

Fish it when the trout might be in the top foot of the water and you still want a fly you can see.

A plain dry is the better test when a fish is rising steadily, leaving a bubble, and you can match a bug on the water. The dry-or-nymph guide is that row. A second fly under the dry adds drag, and it adds a length of tippet a fish in flat water can refuse. If the rises are leaving bubbles, take the nymph off and fish the dry alone.

An indicator rig is how you fish a nymph near the bottom, with the depth set in feet and split shot if the fly will not get down. A dry cannot do that job. It floats, and it tips or sinks once the nymph is too heavy or too far below it. Use the dry-dropper when you think the fish are up. Use the indicator when you think they are down.

Three looks where the dry-dropper is the better first rig:

• Rises that leave no bubble, or fish flashing just under the film. The dry-or-nymph guide already sends that look to a short nymph under a dry. This page is how to build it.
• A few rises, and you cannot yet say whether they are eating the adult or something just under it. One drift offers both. Watch which fly they take. The next drift can be only that fly.
• Grasshoppers in the bank grass, and the holding water tight against that bank. A buoyant dry along that edge covers the fish that will eat a hopper and the fish that will only take a nymph a foot down. If the grass is empty, do not tie a hopper because the month sounds like hopper month. The no-hatch guide is that check.

Fast, shallow pocket water fights both rigs. The float catches current, and so does a bushy dry. Fish that water in close, with the pocket-water checklist. Save the dry-dropper for a run or a bank where the dry can actually drift.

2. What to tie

Start from the floating line and the 9-foot leader in the first outfit. Tie a fresh piece of tippet to the leader tip, the way the knots guide ties tippet on, so you are not cutting into the taper every time you change flies.

The dry has to float with a nymph hanging from it. A Parachute Adams usually will not. Use a buoyant dry: a Chubby Chernobyl, or a Stimulator. Both are easy to see, and the foam or the hackle can hold a light nymph. A size 12 is the calm first size, because it matches 4X. A size 10 is fine on the same tippet if the fly still turns over. An Elk Hair Caddis from the starter box can hold a small unweighted nymph for a first session. If it sinks, it is the wrong dry for this rig. Switch to the foam fly. Do not add a heavier nymph to make the caddis fish deeper.

Tie the dry to the tippet with an improved clinch. The knots guide is the steps, including wetting the turns before you pull. Nip the tag short.

The nymph hangs from its own piece of tippet. The usual place to tie that piece is the bend of the dry's hook, the round wire under the point, with the same improved clinch. Use the turn count the knots guide gives for that X, wet the turns, and pull the standing line until the knot sits at the bottom of the bend. Trim the tag. A tag you leave long is what the nymph wraps on the next cast. Clinch the nymph to the other end of that piece.

The other place is the eye, beside the knot that already holds the dry. Use the eye when fish are eating the dry and coming off, and the knot on the bend is sitting in the hook gap. A size 10 or 12 foam fly can take two knots in the eye. A smaller dry often tips or spins when you do that. If the dry will not ride upright, move the dropper back to the bend. Do not leave a long tag on the dry's clinch and call it the dropper. The knots guide trims that tag short on purpose. A long tag there is how the clinch slips.

Length is the depth you are testing, and it is limited by what the dry can still float.

Twelve inches in moving water keeps the nymph in the top foot, where a fish looking up can see it, and the dry can still drift with the bubbles. Eighteen inches is the longer setting, for slower water. In a slow pool, if 18 inches is clearly short of fish you can see, add a few inches and watch the dry. The moment it skates, cuts a wake, or sinks, you have gone too long. You have not tested either fly while the dry is dragging. A dropper of several feet off a Chubby is not a more thorough test. The indicator guide is the rig that sets depth in feet.

Tippet size follows the fly, then the leader you already have. The tippet guide is the rule: divide the hook size by 3. A size 12 is 4X. A size 16 is about 5X. A size 10 divides to about 3X, so 3X or 4X both fish. On the 4X leader from the first outfit, use 4X tippet to a size 10 or 12 dry. That matches the leader tip. Do not tie 3X onto a 4X leader, and do not tie 4X onto a 5X leader. Thicker tippet on a finer leader tip turns the taper around, and the fly flops.

The piece from the dry to the nymph is the same X, or one size finer, matched to the nymph. A size 16 Pheasant Tail takes 5X. The calm pairing is 4X from the leader to the dry, and 5X from the dry to that Pheasant Tail. The finer piece is the one that should break if the nymph hangs in a stick, so you keep the dry. If the leader already on the line is 5X, stay with 5X to the dry and 5X to the nymph. You give up that break-off advantage. You do not hinge the leader to get it back. Nylon for both pieces. The knots guide is why the improved clinch slips on fluorocarbon. If the dropper tippet lies on the surface and holds the nymph up, rub that piece with silt from the bank. Do not grease it.

Leave the nymph unweighted, or use a small brass bead. A tungsten bead belongs on the indicator rig. On this one it sinks the dry. The gold-bead Pheasant Tail, sizes 12–18 is that brass bead: use the size 16 from the dozen under the dry. Nip every tag before the first cast.

3. Cast it without a tangle

Two flies in a tight loop wrap each other. Cast this rig slower than a single dry, and let the loop open. The rod tip travels a wider arc. Stop the rod firmly enough that the leader turns over. Do not crack the flies.

• False cast once. A second false cast is for when the first one left the flies in a pile. More than that spins the dropper around the leader.
• If the back cast has no room, or the leader is already crossed, roll the rig onto the water and pick it up clean. Do not throw the tangle harder.
• Cast a little upstream of the spot, so the nymph has a moment to sink and both flies drift back toward you. The leader should land in a line, not in a heap on the dry. A heap is drag, and it is the start of a tangle.
• In a breeze, cast more sidearm. A vertical loop is where the nymph meets the dry in the air.

Make the first cast over open water, or onto the grass if the bank behind you is clear, and look at the leader before you cover a fish. A tangle you find there costs a minute. A tangle over the lie puts the fish down.

Before the next cast, glance at the tippet. A wind knot is a small loop you did not tie. Pinch it out if it will come, or cut the tippet and retie. Fishing the wind knot is how this rig breaks on a fish.

The dry should land upright and drift with the bubbles beside it. If it wakes, that drift did not count. Mend, or pick up and cast shorter. The reading-water guide is the lane. This rig does not fix a lane you have not chosen.

4. Read the take

Watch the dry. It is the indicator. You will not see the nymph.

A trout that eats the nymph moves the dry in a way the current did not. The dry dips and stays under. It stops while the bubbles keep going. It twitches, or it slides off the lane. Lift when that happens. The fish often lets go before the dry plunges, the same as with a yarn indicator.

A trout that eats the dry takes the thing you are watching. It disappears in a rise, or it is gone when you look back. Lift then too. You do not get a separate signal for each fly. Anything the current did not do is the set.

A short, smooth lift is enough. A hard sweep on 5X breaks the dropper, or pulls the nymph away from the fish. If you set and come up empty, drift the same lane once more before you change anything. Rocks repeat. Fish do not. If every supposed take is the dry bobbing in the current, you are setting on the river. Wait for a movement the bubbles did not make.

5. When it sinks, tangles, or gets no hits

Change one thing, then repeat the same drift.

The dry sinks. The nymph is too heavy, the dropper is too long, or the dry is too small or waterlogged. Dress the dry with floatant, paste or powder, and dry it with a couple of false casts or a squeeze in a cloth. Do not dress the nymph, and do not dress the dropper tippet. If a dressed dry still sinks, shorten the dropper or swap the heavy nymph for an unweighted Pheasant Tail. If an Elk Hair Caddis is the dry, change to a Chubby Chernobyl or a Stimulator. If no dry you own will float a nymph in this water, you are in indicator water. Switch rigs. A dry under the surface is not a dry-dropper.

It tangles on every cast. Shorten the dropper toward 12 inches. False cast once. Open the loop and slow down. Nip the tags. If the wind is wrapping the flies, cast sidearm, or take the nymph off until the wind drops and fish the dry alone. Retie a wind knot. Do not pull it tight and hope.

Nothing eats. First ask whether the drifts were clean. A dry that wakes tested drag, not the flies. Fix the drift and repeat. If the drifts tracked the bubbles and stayed empty, change the dropper length by a few inches. If the dry is looked at and refused, the nymph is probably pulling it. Shorten the dropper, or take the nymph off and fish the dry alone for a handful of drifts. If the surface is quiet and the run is deeper than the dropper, move to the indicator. Two changes in one cast, a new dry and a new nymph, or a new length and a new lane, leave you unable to say which one mattered.

One line before you move: the dry, the nymph, the dropper length, the lane, and whether the dry actually floated. After a few runs you can see whether you keep fishing this rig in water too deep for it.

Rigging, drag, and this loop get more room in Fly Fishing for Nerds: A Data-Driven Guide to Finding, Hooking, and Landing Trout. Readers can take 25% off ($9.74) with code NERDS25 at Leanpub.

The Riverbank Checklist is the one-page routine for the bank: safety first, then one hypothesis and a short test. The dry, the nymph, and the dropper length belong in that note.