Effective Flies – Tyenna Caddis Grub

Craig ties an underrated and under-utilised fly, the Tyenna Caddis Grub.

When fishing rivers, the pinup insect which captures the flyfisher’s imagination is the mayfly. This is understandable because mayfly are easy to spot on the water, have a lifecycle most anglers are familiar with, and they’re simple to imitate with artificial flies. It doesn’t hurt that they’re also a very elegant insect; and particularly when the duns are emerging, mayfly can trigger excellent dry fly action. It’s no surprise then that fly-tiers devote so much time to creating flies specifically designed to imitate the various stages of mayfly’s life cycle.

With so much attention given to mayflies, other insects which are equally (if not more) important, can be overlooked. Caddis flies (Trichoptera) are a classic example. Found in most if not all trout streams, they invariably make up a significant part of any trout’s diet. In particular, the grub-like caddis larvae are often eaten by trout throughout the day (not just during a narrow hatch window) making them a very important insect for flyfishers to imitate.

My favourite caddis larvae pattern is one of the more imitative ‘nymphs’ I regularly fish. When Euro nymphing, I usually fish it in conjunction with a flashier nymph such as a Blow Torch. It’s also one of the few nymphs I tie with a gold bead-head. I don’t claim to know why a gold bead works better on this fly; it just does. Metallic green bead-heads are also worth trying.

Besides fishing it Euro nymphing, the Caddis Grub works well fished under a dry fly or strike indicator.

One of my favourite captures on this fly was a beautiful brown of around 4lb from the Nariel Creek. Anyone who’s fished this stream containing mostly small trout, will appreciate that’s about the best vindication of a fly you could get! It’s no wonder that I thoroughly recommend this fly to all stream fishers. It is quick and easy to tie and has worked for me all around the world.

A ripper Nariel brown on the Caddis Grub.

Overall, the Caddis Grub has become one of my go-to flies when I’m looking for a more imitative pattern, especially when the fishing is tough.

FlyStream Effective Flies #29 – Tyenna Caddis Grub from FlyStream on Vimeo.


Hook – Heavy gauge grub hook, size 12-14.

Bead – Gold tungsten 3.0-3.5mm.

Thread – Olive 8/0

Rib – Medium gold wire.

Body dubbing – Blended olive and natural rabbit.

Collar dubbing – Semperfly peacock dubbing or Spectra dubbing #47.

Tying Instructions

  1. Slide the bead on to the hook through the smaller hole, with the larger ‘cone’ hole facing to the rear.
  2. Tie in the gold wire, then tightly dub in a tapered body. (I use a coffee grinder to blend the dubbing, approximately 60% olive and 40% natural.)
  3. Wind in the gold ribbing in the opposite direction to the direction the dubbing was wound on.
  4. Finally, dub in a small bit of colour using the Semperfly dubbing behind the bead, and whip finish.