Key To Success!

Come the dying days of the season, a number of river insects can be expected, but one of the most prevalent will be Large Dark Olives

The good news here is this particular upwing species is fairly widespread and tolerates many water types, be it a fertile chalkstream sauntering through meadows, or a tumbling burn, way up in the highlands.

So chances are, a river, or stream near you will have a thriving population.

Hatching duns naturally drift downstream as they ready themselves for their maiden flight. 

For our imitations to copy this to the letter, ideally we need to position ourselves downstream of rising trout, or any pool we suspect to hold fish. 
Our leader material shouldn’t be too heavy (thick) as this tends to “shackle” our fly and thus, prevent it from behaving naturally at the surface.  Tippet materials somewhere between 3-4lb breaking strain are ideal with The Essential Fly 2.86lb Fluorocarbon, or Wychwood 4lb Ghost Mode Tippet being favourite brands.

Obviously, feeding fish should be targeted by placing the fly a good few feet ahead of any rise form, as this gives fish time to respond and react to your fly. 

Granted, a fish will see any fly that’s dropped directly on its head in the rings of a rise. 
However, it now has to turn and pursue a fly drifting downstream, which trout are rarely prepared to do.  Pools can also be searched blind by using the “fan” casting method. 

To effectively comb the water, make sure your fly always alights in a different place every time, as focusing on only a small area is like putting all your eggs in one basket.

On warm Autumn days a floating imitation can be very effective in a #14.

Try a Parachute Adams or Olive Dun.

Large Dark Olive Tying Tips

As their common name suggests, Large Dark Olives are larger than the average Olive we encounter on rivers, so they’re best copied on a size 14 hook

If you care to look closely at newly emerged duns the segmenting along their abdomen is a pronounced yellow banding, which is why Semperfli Pure Silk Danica Primrose is used as a rib. 

CDC is often enough to support the fly, however a few wraps of hackle add extra buoyancy for the more boisterous parts of a stream, as well as giving the finished article an attractive footprint.
Hook:                     Dry Size 14
Thread:                  Semperfli Classic Waxed Thread 12/0 Primrose
Tail:                        Coq de Leon Fibres (or Cock Saddle Hackle Silver Badger)
Rib:                        Semperfli Pure Silk Danica Primrose #4
Body & thorax:     Semperfli Superfine Dubbing Pale Olive / Olive 
Wing:                     CDC Natural
Hackle:                  Cock Saddle Hackle Silver Badger

Related Blog Posts
Fly Tying Materials Quick Links