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An all-purpose fly
Diawl bach means "little devil" in Welsh and is said to have been invented by Welsh fisherman Wyndham Davies.
A model I discovered a few years ago thanks to the videos of reservoir anglers in the UK who use it a lot in their enclosed waters, but also in rivers.
It imitates everything and nothing at once, which is its strength, but basically it was invented to suggest a midge pupe.
It can replace a chiro, but in fact it's a bit of an all-purpose fly that works all year round.
Assembly instructions for the model shown
Using your UTC 70 red or equivalent mounting line, fill your Kamazan B170 hook in size 14 or 12, then come to the bend to attach a few fibers of black hen feather to the tail.
Attach two peacock herls, then cover the body with your mounting silk, then hoop with a peacock herl + kristal flash pearl hooping.
Under the thorax, attach a few fibers of black hen feather, then finish by making a head of mounting silk + UV resin.
Numerous variations can be created by replacing peacock herls with natural pheasant or black pheasant. The strapping can be modified at will to vary the models using copper wire or flashabou or kristal flash.
To be used on strong iron hooks to weight the fly without adding beads in sizes 10, 12 and 14. I mainly use size 10 and 12.
Tips and tricks
It can be formidable whether tipped on a long leader mounted on a floating silk or midge-tip, alone or on a train of 2 or 3 flies spaced 1 to 1.5 m apart.
The leader can be made up of 3 diawl bach, 2 unweighted and one weighted tippet or chiro nymph, to get down faster in the water column.
It's a good idea to make a tight cast with the leader in line with the line, and keep this tension while letting the flies sink. Bites can occur at this point, without animation. You need to look at the tip of your line and/or the leader to detect discreet touches, a displacement of the line, but sometimes the pull is straightforward and unequivocal.
It's interesting to count and fish at different water heights to find out which layer and depth the fish are in. Start by animating after 5 seconds of immersion, then 10 seconds, then 15 seconds, etc... Until the fish are found.
We often animate by knitting, alternating with pauses, but there's nothing to stop us from doing faster animations to find what appeals to the fish.
Another set-up consists of using one or two diawl bach on an intermediate line (slow or fast) above a streamer, FAB or booby.
FAB and Booby keep the fly, or flies, in a layer of water for longer.
It's also great for washing lines with a large dry tippet (e.g. deer sedge), a FAB or a booby. It can be used when you've found the right water height and keeps your flies in it. This can be done with midge tip silk or intermediate to plunging silk.
