Barbless Flies

Match The Hatch

The Iron Blue

All the information you need to help get the most from your Iron Blue 'Match The Hatch' selection of flies.

With the Trout season starting on the majority rivers throughout the UK in April, fly anglers thoughts switch from Grayling to Trout. One of the first insects which pops up on the fly anglers radar iacross the whole of the UK is the Iron Blue.

The Iron Blue is a member of the Baetis family, there are three Iron Blues native to the UK, these are Alainites muticus, Baetis niger and Baetis digitatus, for the purposes of this email we are treating them all as one (Iron Blue is a term used by anglers to represent all three different insects - which are very similar). Iron Blue's are only found in running water, it does not seem to matter the strength of the flow. Iron Blue's are found throughout the British Isles in all types of river and stream. They are easily identified in early and late season (as at present everything seems to be running at least 2 weeks late) as they will be one of the only up-winged species to be seen, with a dark blue/purple body and light wings with dark grey veins. Iron Blues are only fairly small, measuring roughly 1cm long (a size 14 to 16 hook).

Iron Blues are found in every part of the British Isles. They seem to be especially prolific in any river which is fast flowing. But, as with most of this up-winged family of flies, the Iron Blue can be found in all running waters.

Iron Blue - Lifecycle

Iron Blues are known as the '12 til tea' fly, as they normally hatch prolifically from noon until teatime. Unusually for insects they have generally hatch twice a year - usually in May and September, this makes them great flies as far as the angler is concerned - when there are no Mayflies about use an Iron Blue imitation in May, then in September, try a Parachute Iron Blue.

The Iron Blue's lifecycle is:

Nymph: An 'agile darter' which can be found in and around any weed beds.
Emerger: A prime candidate for trout food, the emerger breaks the water surface to transform into the Dun.
Dun: Hatches on the surface and pauses to dry its wings - a prime target for a hungry fish. At this stage the Iron Blue has a dark blue/purple body and blue-grey veined wings.
Spinner: After mating the Adult female will crawl down bank-side vegetation to lay her eggs, trout are not too interested in this stage. However, the trout do take an interest in the Iron Blue as it returns to the surface, in its spent form. They are also known to deposit eggs on the water surface, just like a mayfly.

From a fly fishing perspective the stages which we must try to imitate are:

Nymphs - mornings until 2pm
Emergers - from noon to 3pm
Duns & Spinners - from noon to 4pm
Spent - from mid-afternoon until dusk

The Iron Blue hatch usually starts in late April/early May and is very prolific until the end of May/beginning of June, then starts again in late August/September.

Match The Hatch - Iron Blue Imitations

The most popular imitations for Iron Blues are any of the flies below (all contained within your 'Match The Hatch' selection), don't worry if you don't have these exact patterns, as anything which is in the general colour, profile and size will do. These flies should be fished as you would any other dry fly, the Iron Blue Upright being especially buoyant. These dry flies should be used as soon as you start to see the hatch appear (remember early hatches of Iron Blues don't last long), this can be anytime from 12:00 until 17:00, depending upon weather conditions.

Iron Blues are generally pretty easy to spot (especially in April - as they are generally the only up winged fly you will encounter on the river, and they will have a dark purple/blue body). Later, in April, it is often confused for the Large Brook Dun (which is very similar). Remember these flies only have 2 tails.

The Iron Blue is a fly which is known for hatching in even the most inclement of weather, one of the only flies you can just about guarantee will hatch on your visit to the water in any month of the trout season. Outside of its normally hatch calendar the Iron Blue can still be found in the shady parts of the river.

Iron Blue Nymph

If you are fishing in a morning or cannot see any signs of an Iron Blue hatch, then nymphs are the way to go, in early season it is sometimes more productive to use a brighter nymph, then the drab more imitative ones. Always keep in mind how deep and how fast the water is when nymphing in early season, that will tell you how heavy a nymph you need to use. All you need to remember when fishing nymphs in the early season is that you need to be near (or on) the bottom, if you're not getting snagged up every so often, you're not fishing deep enough.

Iron Blue Emerger

Try fishing this Iron Blue emerger with no fly dressing first. It will float for the first few casts and then it will slowly sink under the surface, this allows you to see which method works best and which the fish are interested in on that specific day. If you want your emerger to float high then use a powdered style floatant to keep it riding high on the water.

Don't be too afraid to let the pattern sink slowly and then manipulate it with your fly rod to help it rise through the water column, this perfectly imitates the emerging insect.

Parachute Iron Blue

The Parachute style of Iron Blue you see here is tied to imitate the insect which has hatched and is resting on the surface, waiting for its wings to dry out - this is ideal for a trout to intercept it (as it cannot escape). Only fish this pattern (and the Iron Blue Upright below) once you can see fish rising.

When fishing with a parachute-style fly only apply floatant to the post, as you want the fly to fish in the surface film (not riding high on it like the Iron Blue Upright below).

Iron Blue Upright

An imitation of the Adult Iron Blue, this variant is fished dry and sits proud on the water surface. It can be used in either early (April/early May) or very late in the season - September/October.

Apply floatant to the full hackle, this allows the fly to stand on the water's surface with only the tips of the hackle making indentations on the surface - it is believed that the pattern of indentations is the trigger to the fish taking the fly.

Iron Blue Spinner

Once the Iron Blue has returned to the water to lay its eggs, the females die and float on the surface, this is the spinner. The spinner is an easy target for Trout, and they can gorge on them in the early evenings. Just treat the wing and thorax to some floatant so the fly rides high on the water.

The best water to taget when fishing with spinners are the slower back eddies, as this is where fish partol looking for any insects which are trapped in the meniscus - they make easy pickings!

Iron Blue - Hatch Notes

One of the best places to start when fishing rivers in the early season is to understand which insects are hatching under the water. The above patterns cover the basics of the 4 main hatch stages that you’ll see on your local river.

Once you can identify which stage to imitate you will have the perfect imitation already in your 'Match The Hatch' selection. Broadly, every insect that you’ll find hatching in the river will have a lifecycle that can be explained in 4 stages: Nymph, Emerger, Adult (Dun) & Spinner.

In the early season, there will be lots of nymph activity under the water all day but only sporadic hatches of dry flies so you will need to choose your fly specifically to target what is happening at that time. Once the fish have survived the winter having not eaten much, as soon as fly life starts to appear in the river the fish will go on a feeding frenzy, identifying what the fish are feeding on is the best place to start.