Fishing flies come in thousands of different patterns, but understanding them becomes much easier when you stop concentrating on individual names and instead think about **what type of fly it is and how it is designed to fish**.
Most fishing flies can be placed into a relatively small number of broad groups. There is some crossover between them, and not every fly fits perfectly into one category, but understanding these groups gives you a much better foundation for choosing flies.
## Dry Flies
Dry flies are designed to fish on the surface of the water.
Many imitate adult aquatic insects such as upwinged flies and caddis, while others represent terrestrial insects such as ants, beetles and daddy long legs that have fallen onto the water.
Some dry flies are very specific imitations. Others are deliberately general and simply present the fish with something that looks like a plausible insect.
Typical examples include:
- F-Fly.
- Griffiths Gnat.
- Elk Hair Caddis.
- Parachute Adams.
Dry flies are primarily associated with trout and grayling fishing, although surface flies are used for many other species.
## Emergers
Emergers represent insects during one of the most vulnerable stages of their lifecycle - the transition from an underwater nymph or pupa into the winged adult.
This often takes place in or immediately beneath the surface film.
Emerger patterns therefore frequently sit partly underwater rather than floating completely on top of the surface.
Fish can become extremely focused on this stage during a hatch, sometimes ignoring fully emerged adult insects in favour of emergers trapped in the surface film.
Typical examples include:
- Klinkhamer.
- CDC Shuttlecock.
- Suspender-style emergers.
The Klinkhamer is a classic example of an emerger. The parachute hackle supports the fly at the surface while the body hangs below it, representing an insect emerging through the surface film.
## Nymphs
Nymphs are subsurface flies primarily designed to imitate immature aquatic insects and other small aquatic food.
They can be extremely lightly dressed or heavily weighted with tungsten or brass beads.
Some nymphs are designed as close imitations of particular insects, while others are much more general patterns that could suggest several different food sources.
Common examples include:
- Pheasant Tail Nymph.
- Hare's Ear.
- Diawl Bach.
- Copper John.
- Perdigon-style nymphs.
Nymphs can be fished from immediately beneath the surface right down to the riverbed.
## Wet Flies
Wet flies are designed to be fished beneath the surface.
Unlike many modern nymphs, they often incorporate soft feathers or hackles that move naturally in the water.
They can represent emerging insects, drowned insects, small aquatic creatures or simply something alive and edible.
Wet flies are particularly important in traditional British river and loch fishing and can be fished individually or as a team of flies.
## North Country Spiders
North Country spiders are a distinctive British style of wet fly.
Despite the name, they are **not intended to imitate spiders**.
They are generally very sparsely dressed, usually consisting of a simple body and a soft feather hackle.
When fished in moving water, the soft hackle fibres move and pulse in the current, creating an impression of life without necessarily representing one specific insect.
Patterns such as the **Partridge and Orange** and **Snipe and Purple** are classic examples.
## Streamers
Streamers are generally larger subsurface flies designed to suggest small fish, fry, leeches or other substantial prey.
Movement is normally an important part of their effectiveness.
They can be retrieved actively, swung across currents or manipulated through the water depending on the fishing situation.
Streamer fishing is particularly effective for larger predatory trout and is also widely used for many other predatory species.
## Lures
The distinction between a streamer and a lure is not always clear, and anglers sometimes use the terms interchangeably.
In UK trout fishing, **lure** commonly describes a larger, highly visible fly designed to attract or provoke a fish rather than closely imitate a particular natural food item.
Colour, movement, flash and profile can all be important.
Patterns such as Cats Whiskers, Humungous and various brightly coloured stillwater patterns fall broadly into this category.
## Attractor Flies
Attractor flies are designed around the idea of attracting a fish rather than accurately copying a particular food source.
They may use:
- Bright colours.
- Flash.
- Hot spots.
- Unusual movement.
- Strong silhouettes.
- Contrasting materials.
An attractor can still resemble natural food, but exact imitation is not its primary purpose.
Many highly successful modern nymphs, dry flies and stillwater patterns combine elements of both imitation and attraction.
## Salmon and Sea Trout Flies
Salmon and sea trout flies form a substantial category of their own.
They include:
- Hairwing flies.
- Shrimp patterns.
- Traditional feather-wing flies.
- Tube flies.
- Hitch flies.
- Surface flies.
Unlike trout flies, salmon flies are generally not intended to represent something the salmon is feeding on in freshwater.
Instead, their size, colour, movement and presentation are used to encourage the fish to take.
## Predator Flies
Predator flies are designed for species such as pike, perch and other predatory fish.
They are often much larger than conventional trout flies and commonly imitate:
- Baitfish.
- Fry.
- Frogs.
- Other substantial prey.
Large synthetic materials are frequently used because they create considerable movement and profile without becoming excessively heavy when wet.
## Saltwater Flies
Saltwater fly fishing encompasses an enormous range of species and therefore an equally broad range of flies.
Depending on the target species, saltwater flies may imitate:
- Baitfish.
- Shrimps.
- Crabs.
- Prawns.
- Squid.
- Other marine prey.
Saltwater flies are usually tied on strong, corrosion-resistant hooks and often need to withstand considerably more punishment than typical freshwater trout flies.
## Where Do Some Flies Fit?
Not every fishing fly fits neatly into one category.
A small streamer may closely imitate a fish, while another streamer may be almost entirely an attractor. A wet fly may suggest an emerging insect without being a specific imitation of one particular species.
This doesn't really matter.
The categories are useful because they help us understand **how a fly is intended to fish**, not because every pattern needs to be given a rigid classification.
## Key Takeaways
- Thousands of individual fly patterns can be understood through a relatively small number of broad categories.
- Dry flies fish at the surface.
- Emergers, including the Klinkhamer, fish primarily in or around the surface film.
- Nymphs imitate subsurface aquatic food.
- Wet flies and North Country spiders use movement beneath the surface.
- Streamers generally suggest larger prey.
- Lures and attractors rely more heavily on colour, movement and other triggers.
- Salmon, predator and saltwater fishing have developed their own specialised groups of flies.
- Some patterns cross several categories, and there is no need to force every fly into a rigid classification.
- Understanding **how a fly fishes** is more useful than simply memorising what category it belongs to.
