Fishing the dry fly on rivers

Casting a dry fly to a trout and seeing the fish take it or turn away at the last moment makes the heart of even the most seasoned angler beat faster.

Trout often feed at the surface of the water on newly hatched aquatic insects or female flies returning to lay their eggs. Terrestrial (land-based) flies and other insects are also important food items as summer progresses.

Matching the hatch

If you want to catch a feeding trout, your best chance is to offer it an imitation of the natural fly it is taking. By looking at the water or along the river bank you can discover what the trout are feeding on.

Size is an important feature. Few fish are duped by a fly too small or too large. Also take into consideration the shape and colour of the natural insect’s body, legs and wings. Is the dry fly designed to copy a sedge fly or a dun (a newly hatched upwing fly), an egg-laying spinner or a terrestrial? Wings don’t have to be included – often the blur of the hackle is a sufficient suggestion.

Rise forms

Trout feeding at the surface reveal clues about the insects they are consuming. The simple or plain rise is the commonest form. Trout taking duns, motionless adult sedges and most terrestrial insects produce regular concentric rings on the surface — sometimes with a tell-tale bubble.

When a trout moves quickly to grab a fly off the surface, it causes a splash, displacing a lot of water. This is the slashing rise, a signal which suggests the trout is taking fast-moving, hatching sedge pupae. If sedges aren’t around, the trout may be feeding on large terrestrial insects. Fish a sedge pupa imitation in the surface film of the water. If that fails, try a large terrestrial.

The dimple, sip or kiss rise is difficult to detect on rippled or fast water. It’s much easier to see on calm stretches. The trout moves unhurriedly to its prey – knowing the food can’t escape – and sucks the insect in without breaking the surface of the water, producing very gentle ripples.

Spent spinners, stillborn flies or those trapped in the surface film are the likely items the fish is going for here. A trout feeding in this way is usually stationed very close to the surface and feeding frequently. Because there is often plenty of food, trout do not move very far to feed. Present the fly in line with the trout.

Proper presentation

Selecting the right pattern is half the problem; the other half is presenting the fly correctly. Drag, the main concern for the dry-fly angler, occurs because the speed of the current varies across the surface of the river, and the line pulls or ‘drags’ the fly af* an unusual speed. A fly which doesn’t drift exactly where the current takes it looks unnatural, and trout refuse it. There are exceptions to this (mainly egg-laying sedges), but 95% of your presentations must be drag-free.

You can overcome drag by casting the line leader and fly on to water which has a minimum variation in current speed. You can also cast slack or excess line on to the water, so the current has to straighten it before drag can begin.

If you cast across the current, any faster water creates a downstream belly in the line and causes the fly to drag. You can avoid this by mending the line — flicking the line upstream so that the belly moves upstream of the fly.

On smooth, unrippled surfaces mending line may alarm fish. A reach cast moves the line in the air on the forward cast so that it lands upstream of the fishing zone. The longer a fly is allowed to drift, the more likely it is to drag. Another answer is to fish with short drifts.

Presenting the fly downstream offers some advantages – the fly is the first thing the trout sees, and the leader and line are less visible. Fishing this way can be a very effective way of taking shy fish.

Fishing tips

If rising trout refuse the artificial fly, there are a number of things you can do. In moderate to slow water – where trout can take a long, hard look at the dry fly – use a pattern a size or two smaller than the one you tried first. You can also try a low-riding pattern which rests in the surface film. Copying an emerging or trapped fly in this way is often successful. In fast water where trout might easily miss a fly, move up in size to make sure they see your imitation.

Another possibility is to offer them a food source such as a bushy sedge or a beetle pattern that might be more attractive. If that fails cast upstream and, as the fly drifts 30cm (1ft) or so in front of the trout, twitch it gently. This singles it out from motionless natural flies and gives it some life. Adding a bit oflife to the fly is perhaps one of the most difficult characteristics to give to an artificial.

If trout aren’t rising or if you can’t find them, try searching the faster water with an attractor pattern such as a Wickham’s Fancy. Or cast a terrestrial pattern in slow water so that it lands with a ‘plop’ that attracts the attention of lethargic fish. At dusk use a bushy sedge pattern. Fish it downstream, giving it an occasional twitch. Using a finer leader (which makes the line less visible) or softer nylon (which allows a freer drift) may also help. Fishing the dry fly often means continually changing your approach to tempt shy fish. The problems that the trout presents are part of its charm.