How to tie IOBO emerger

iobo emerger

About IOBO emerger

The original IOBO emerger or IOBO Humpy, as it is also known, was designed by Jack Tucker and for years was a somewhat secret pattern, only known to the privileged few. But this tiny non-specific emerger caught on fast and should not be under estimated, it is truly a deadly pattern, and a absolute must have pattern for all grayling fishermen. This little variant shown here has the addition of a small crystal flash trailing shuck that has turned many a possible blank day into a bonanza! 

IOBO emerger pattern

Hook: Mustad C49S # 16-22
Tying thread: Grey
Trailing shuck: Two strands of crystal flash
Body/wing: One CDC hackle

Although there is only one single CDC hackle in this pattern, the key to getting it right is using the correct CDC hackle.  You should look for a hackle that is not too short, you need the length for wrapping the body and then the shell back and wing. But the hackle should also have long dense fibres that will give a little more volume to the body and wing if tying them in larger sizes. I find that natural (un-dyed) hackles are best as some dying processes make the hackle stem brittle causing it to break when wrapped.

Rain hatch

When and how to use IOBO emerger:

The IOBO emerger can be fished whenever there is surface activity going on throughout the year, although I have found it to be less effective in the autumn, in larger sizes than earlier and later in the season. Use it as a searching pattern when there is no activity, letting it dead drift over pocket water or possible holding spots.  It has also fished well for friends, static, on still waters especially on flat calm days when buzzers or on the go.

Step by step how to tie IOBO:

When dressing this pattern its important that the crystal flash shuck is tied in long and remains long throughout the whole tying procedure. The long crystal flash fibres enable you to hold them out of the way with one hand, when the CDC fibres are collected with the other, to be folded over to form the shell back and wing. Not until everything else is finished can they be trimmed down to a few centimetres long. It’s not the most robust pattern around, the delicate CDC shell back is easily broken by the small needle sharp trout teeth, but ist so quick to tie, I find it no trouble tying another one on…

  1. Attach your grey tying thread to the hook shank. Wind your thread back to just before the hook bend and then forward in open turns to just behind the hook eye. This will give the CDC more purchase.

2. After you have selected an appropriate CDC hackle tie this in 90 degrees from the hook shank with a little of the stem showing.

3. Tie the stem of the CDC hackle along the hook shank and place your tying thread at the tail base.

4. Attach your hackle pliers to the tip of the CDC hackle and wrap back towards the tying thread. make sure that you brush the CDC hackle fibres back with each turn forming the wing material. Tie off.

5. Once secure wind your tying thread forward through each turn of hackle stem and finish just behind the hook eye.

6. Grip all the CDC fibres with your right and fold over the body to form the shell back, similar to a Humpy. Secure with a few turns of tying thread, close to the hook eye.

7. Lift the wing and whip finish under the wing behind the hook eye. Remove your tying thread and trim off the wing tips to the desired length.

Iobo emerger

You can also tie the IOBO variant, with a little Crystal flash shuck in the tail as shown here

How to tie IOBO emerger

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