catgut

Catgut Biothread Pupa is one of the best fly when caddis flies are hatching. It is very easy and fun to make it, no need special skills and any beginner tier can tie this fly in 5-8min.
Caddis nymphs and pupa should be all the time in fisherman boxes. These flies are very efficient and productive because these insect are a good source of energy for fish due to sizes and qty of them. At the end of May until in the first part of August with a peak in July , these insects are all over the rivers from Europe and USA. You can find in waters under big rocks in huge numbers, close to river bank also on the gravel. For this reason you will find a lot of imitations from country to country and from region to region.

The version of pupa tied with catgut biothread is probably the best one because:
-has a realistic look
-very resistant at fish teeth
-easy to tie
-catgut biothread has a special property – translucency that no other material can imitate it

In the past, catgut was a secret material used in fishing competition by Polish fisherman and Czech fisherman. It was used the suture version ( made of natural collagen). Now this material is difficult to find. Troutline developed a special version of this material, special treated to be high resistant at solvents and at water and is called Troutline Catgut Biothread.
The material is available in different sizes, very thin to thick and is used not only for tying caddis flies but also for different bodies of nymphs. Catgut cannot be used for dry flies or emergers because this material soaks water and will sink the fly.
Another property consist in doubling the volume when soaks water. So when you tie with the material wet , when gets dry you will see spaces between ribbing. But soon you will put in water will soak and will look in the proper way.
Bellow I tied a few version of caddis pupa:

The following one is simple tied with catgut in natural color, size M on #12 hook:

Catgut and Partridge Pupa:
Recipe:
*Hook size #12
*Underbody thread:Troutline Yellow Caddis
*Body: Catgut Biothread – natural color size M
*Hackle: partridge grey neck feather in natural color
*Thorax: Mad Rabbit Dubbing – natural color

The most simple version ( used when these insects are not close to the emerging stage)

Catgut and Peacock Pupa:
Recipe:
*Hook size #12
*Underbody thread:Troutline Yellow Caddis
*Body: Catgut Biothread – natural color size M
*Thorax: Peacock herl

Another version that I like a lot and I use a lot is tied with CDC:

Catgut CDC and Partridge Pupa:
Recipe:
*Hook size #12
*Underbody thread:Troutline Yellow Caddis
*Body: Catgut Biothread – natural color size M
*Hackle: partridge grey neck feather in natural color
*Second Hackle: CDC natural black
*Thorax: Mad Rabbit Dubbing – natural color

A few words about the last version:
I like it due to special properties of CDC in water: translucency, movement, color and air bubbles caught by material when is wet. I noticed that is efficient in slow running waters and works very well even when the fly is almost stopped. So I prefer to use it in deep pools and jig it a little bit to induce the attack of the fish.

Lets start with the step by step:

First I soak the material in a glass with water for 3-5min until gets soft and transparent. Then I fix it using Troutline Yellow Caddis body thread

Then I make an underbody only with body thread in the shape of aubergine (eggplant). Then I cover it with the catgut like in photo. I leave enough space to fix the hackles and to make the thorax using dubbing

Then I fix the partridge feather and the CDC feather (from the tip)

The final step is to make the thorak using mad rabbit dubbing. I prefer this material instead of others, I like how looks in water, the shades from black to spotted grey:

The final fly looks like this:

When gets wet look fabulous, the look is completely different and very realistic:

Have fun tying and fishing! 🙂
Lucian

Fishing with nymphs in this period is probably the most effective style. Levels of rivers are high, more or less clear and fish are eating in frenzy.In April the most efficient flies are GRHE in different variants. Also peeping caddis are efficient tied in different styles. At the end of the June caddis pupae nd caddis nymphs without case start being efficient. We tie them with body glass, with yellow wool, with latex or with yellow silk thread. A very efficient but in the same time easy to tie with a high realistic look is caddis catgut nymph. The fly tied in this way is perfect on big hooks , for example in north countries like Sweden, Denmark and Finland the fish prefer consistent food so if you will tie it on size #8-12 will be perfect. On continental Europe size #10 and 12 is perfect but in some condition you can make it on size #14.
Materials:
Hook: Demmon DGH 900 BL or Demmon COmpetition G600
Thread: yellow fly tying thread
Underbody: yellow fly tying body thread
Body: catgut biothread in natural cream color,
Torax: black seal dubbing seal substitute for tying ( more economical and “save the baby seals” materials)
Bead: tungsten beads in any color you like

I advice to keep the catgut biothread in warm water for 5-6 min until will became transparent. The material is almost solid and stiff like a wire. If is kept for a while in water will became soft , translucent and easy to work with. Then you should make the under body of pale yellow body thread, to imitate the color of the insect.if you like to be more closer to the natural shape of the insects is better to make the under body in the eggplant shape and not carrot shape. Wrap the catgut in tight turns (because the catgut will have an increased volume after soaking in water). Add black dubbing to make the torax and the fly is ready!
When became dry the catgut turns will have spaces but don’t worry, is normal. After soaking in water will became nice looking, exactly like the insect body. Is strange and interesting in the same time how this material can provide such a realistic look.
So lets tying, bellow are the photos with step by steps:

This is an old series of catgut micro nymphs tied 6 years ago for grayling in North Transylvania.  I tied them on small hooks from size #14 down to #18. I was  impressed by  natural shades and colors,  how looks the material when  is wet and I was impressed by   the  texture very close to the insects texture and translucency .

Bellow is a  step by step for these simple but fantastic nymphs:

I  left the catgut for 5 min in warm water  ( body temperature ) until  started to be translucent and soft.  Normally the material is stiff and hard like a metallic wire but after keeping it in water started to be soft and easy to work with. I used a neutral  thread (a white)  but   colored fly tying threads can  be used to give an interesting shade. Small pinches of dubbing was added from time to time to provide a hairy body look.

And now here are the nymphs tied with this material:

And how look the flies when are wet :

It is impossible not to love them !

For those interested in recipe here  it is:

Hook: Daiichi D1130 #14-18

Thread: white Uni 8/0 or Trico Uni Thread

Body: Catgut Biothread in natural color

Dubbing: Mad Rabbit Dubbing in natural color