Having fly-fished for 30 years on and off, I’m still learning about the differences between dry and wet flies. But here’s my take on the differences, to help all those new to trout fishing.
Dry flies are fished on the water’s surface. They imitate emerged aquatic insects or flying terrestrial insects that have settled on the water’s surface. Wet flies are fished mid-current. They are imitations of emerging aquatic insects, fish eggs, small baitfish or worms that live in the water column.
Here’s how to tell the difference, what makes each type of fly effective and how to use a dry fly vs. a wet fly.
What is a dry fly for trout fishing?
Fly anglers design dry flies to float on the surface of the stream, river or lake.
Due to a structure that includes plenty of surface area and stiffer material, a dry fly is more likely to stay afloat in the surface tension.
Floatant, frequently silicon-based liquid or powder, is commonly applied to the fly to ensure it doesn’t sink.
Dry flies imitate specific insects such as emerging aquatic bugs like mayflies or caddisflies that are turning into dun or young adult fly.
Or they may imitate an adult female laying eggs on the water or a spent or dying adult.
These creatures float either on the water’s surface or in the sub-surface layer as they swim towards the sunlight and air.
Once airborne, they mate, then die, falling back onto the water’s surface where they again become trout fodder.
Alternatively, dry flies imitate other flying insects that have landed accidentally on the water’s surface.
Terrestrial insects that are part of a trout’s diet include midges, gnats, crane flies, ants, blowflies, cicadas, beetles and more.
The most popular dry fly patterns are called: Royal Wulff, Parachute Adams, Elk Hair Caddis, Stimulator, Pale Morning Dun and Cicada.
Fun Fact: In New Zealand, we get colossal trout known as mouse eaters in certain seasons (called a mast season) when forest food is so abundant that there is an explosion of the mouse population. To catch these trout, anglers use dry flies that imitate mice.
What is a wet fly for trout fishing?
A wet fly is designed and created to ‘swim’ below the water’s surface.
Wet flies trick trout into mistaking them for trout food, such as emerging aquatic insects making their way to the surface, small fish or crustaceans, worms or other freshwater bugs.
Wet flies are constructed from materials like feathers, fabrics, and furs that are soft and malleable.
The use of modern new materials means they flow and flutter in the river current, replicating movements that trick the trout most effectively.
Wet flies are designed to ‘swim’ midway in the water column using either a floating fly line or a sinking fly line.
Weight can be added to a wet fly hook using a bead, or the line can be weighted using split-shot if it’s desirable to get the fly deeper in a pool.
Also, wet flies are more hydrodynamic and designed to drag quickly through the water.
Wet fly fishing is a good technique for beginners to use.
It requires less finesse with casting as it is not as important as how the fly lands on the water.
A hugely popular type of wet fly worldwide is the Woolly Bugger.
Other traditional wet flies that use different designs and construction are variations of the Hare’s Ear, Red Setter, Eggs, and Grey Ghost.
Summary of the differences between dry flies and wet flies
Dry flies
- Imitate adult insects that exist on or above the water’s surface
- Have a stiff hackle and greater surface area
- Created on lighter hooks that assist the fly to float
- Often look like the specific insect they are imitating
- Require a floatant to help keep them afloat
Wet flies
- Imitate insects found in the lake or river
- Weighted, so they sink either to the bottom or ‘swim’ in deeper water
- Slimmer with a soft hackle that flutters in the current
- Weight is applied either using a heavier hook or by adding a bead
- Resemble multiple types swimming insects or fish
- Created to swim and bob in the water column
Fun Fact: The hackle is the feathery plumage behind the eye of the hook.
What makes a Dry Fly effective?
A dry fly needs to land lightly on the water’s surface, so it doesn’t spook the trout.
Dry fly patterns are usually cast using a floating line and tapered leader.
An excellent dry fly needs to dead drift freely in the current – without creating drag.
The most effective dry fly mimics the profile of a lovely meal when viewed by a trout from below.
Types of dries can imitate cicadas, beetles or blowflies that have blown onto the water.
What makes a Wet Fly effective?
According to fly fishing experts, wet flies mimic a multitude of different trout foods.
My guess is this is because of the wet flies’ fluid movements.
Wet fly patterns imitate emerging insects making their way through the water column.
An effective wet fly could trick a watching trout into presuming it is a small baitfish hanging out in a light current.
But wet flies can also mimic the silhouette and color of a worm, small freshwater crayfish or shrimp.
A traditional wet fly is slim in design and used for multiple tactical objectives.
Fun fact: Worms are often spoken of as a go-to fly when all else fails.
How to use a dry fly
Dry flies are cast using a floating line and long tapered leader so that the fly lands delicately on the surface of the water.
Dry flies can drift with the river current without any tension created by the fly line or leader.
Unintentional drag is an unnatural event that quickly alerts the fish that it is not a free-floating insect floating on the surface.
Maintaining a good dry fly dead drift usually requires the line to be ‘mended’ so that the drift continues for as long as possible.
Applying floatant like Loon Aquel (which is my favorite) to the fly before getting anywhere near the water is very effective and easy to keep the fly from sinking.
If the fly does get water-logged, you can use a floatant powder to refresh the floating properties of the fly.
Another way to dry the fly is to falsely cast it several times, getting rid of excess water.
How to use a Wet Fly to catch trout?
Wet flies are attached to either a floating fly line, a sinking tip attached to a floating line, or to a sinking fly line.
When casting a wet fly set-up, it is a simple matter of casting across the stream or river or at a 45% angle.
The weighted fly will sink as the line moves down and across the current until it finishes directly downstream of the angler.
Once the swing is complete, this is often a good time to tweak the line which might encourage a fish to strike.
Wet fly patterns are retrieved using a variety of methods, but a favorite one is the figure-of-eight retrieve, or retrieved with a motion to resemble a swimming fish or an injured insect.
Experienced fly fishers will not simply strip in fly line to keep in contact with the fly pattern but instead will try a variety of methods developed as their personal preference.
Fish need tricking into thinking your artificial fly is food, which takes changing tactics, often from one cast to the next.
The critical point is that the method you use should keep in direct contact with your fly so when the fish strikes, you have the best chance to set the hook.
It is also essential to keep your retrieval smooth and not bounce around too much, especially in small streams where the vibrations created by your movements can easily spook the very fish you are trying to catch.
When should I use a Dry Fly for fishing for trout?
Dry flies are the right flies when there is a hatch of aquatic insects, be that mayflies, caddisflies, stoneflies, or the many other types of flies emerging from their life in the water to mate.
Some rivers are infamous for their huge aquatic insect hatches, while others are less productive.
Hatches often take place in the evening when the water temperature has warmed up during the day.
The time of the year varies from location to location but is most often in the summer months.
When can I use a Wet Fly when fishing for trout?
You can use a wet fly at any time of the year, or streams, small rivers, large rivers with a steady current and lakes.
A wet fly rig is often used when the water is murky, and you are doing what’s called ‘fishing blind.’
When fishing blind, you don’t know exactly where the fish are sitting, which means you cover a section of water by casting steadily, working your way downstream.
Also, if the sun is behind the clouds and the water is choppy, fish are more likely to be in the shallower water, making them a good target for various kinds of wet flies.
Alternatively, the trout may be hiding in a deep pool on a sunny day. That’s when the weight of the wet fly will get you down to where the fish are feeding.
This is also when you might choose to use a nymph fly which could also be considered part of the wet fly category.
Nymphs like wet flies will help you get into deeper water by using heavier hooks, tungsten beads, and split shot.
Make your own flies to catch trout?
An excellent way to learn about aquatic insects and fly types is to tie your own flies.
You will learn the main difference between the different kinds of flies and the varieties of aquatic and terrestrial insects.
Another significant difference is that you will fill your fly box much more cheaply than buying flies at the fly shop.
Experienced anglers know which was the best fly to use in each situation.
For most of us, however, it is trial and error and continual learning. See you on the river!