During the spring mayfly season a few years back I fished on three consecutive weekends at Millbrook. I spent many frustrating hours attempting to deceive the trout that were cruising crystal clear water just offshore, visibly feeding on the abundant mayfly nymphs. Each anticipation-filled cast would land somewhere ahead of the trout, only to follow the same depressing script: I’d see my target change direction, head towards the fly, and then at the last moment, turn away in disdain. I tried lighter tippet and every brown nymph I could find in my fly box. Through sheer persistence I somehow fooled a couple of the smaller fish: one on an old size 16 brown unweighted nymph and another on a size 14 Pheasant Tail. But there had to be a more effective way.
On one weekend I captured a nymph or two and found some shucks to examine. They were surprisingly long, yet slender, with clearly segmented bodies. One of my fellow anglers (and also a keen fly tier) sent me a photograph of a similar nymph shuck from Harcourt Reservoir. Desperate, and disappointed at my lack of success, I decided to tie something a little more realistic, hoping to reverse my fortunes. I started thinking about mayfly nymphs and all I had read and learned over the years, and pondered some key ideas:
- Frank Sawyer sketched some amazing diagrams of swimming nymphs and discussed how they might be fished. He then developed the PTN (Pheasant Tailed Nymph) a deadly yet simple fly, and a staple fly of the modern nymph fisher.
- Victorian-based angling author Lance Wedlick was always extolling the virtues of the fiery brown seal’s fur nymph, and;
- Wedlick devoted a chapter in his book ‘Trout on a Fly’ to discuss the benefits of fishing a flat-bodied nymph (he did include a pattern but it involved a bit too much mucking around for my liking… something about soaking a fly in resin and squeezing it with pliers. I am a bit of a lazy tier and have a preference for the simple.)
I was convinced the key lay in a segmented body that was broad yet flat: really skinny when viewed side on. I experimented with some small vinyl rib over the next few nights until worked out a satisfactory method. I then used the elements of two other successful flies: the PTN and the Seals Fur fly. The resulting pattern was:
- Hook – Size 10 long nymph hook (Kamasan B830).
- Weight – 5-7 turns of .20 lead wire.
- Tail – Fibres from pheasant tail feathers.
- Body – Small brown vinyl rib.
- Thorax – Fiery brown seal’s fur.
- Wing-case – Scud back.
The fly turned out to be quite easy to tie and it didn’t take long until I had the proportions looking right; a fairly good match for the real thing.
Now for the road test: I organised a trip with friend Carl to Millbrook. We started early in the morning and it wasn’t long before the swallows began working. It was too early for mayfly but there were a few midges hatching. The trout however were not obviously feeding, with just the odd fish rising here or there. We tried fishing midges and Carl missed a fish. Yet I had had no luck, no takes at all. I switched over to the new skinny nymph in anticipation of a mayfly hatch: fishing a double team under an indicator. I had only cast out for 30 seconds when the indicator dipped while I was chatting with Carl (yes I missed it). I cast out again and watched like a hawk: less than a minute later I struck to a shifting indicator and felt the weight straight away. It turned out to be a solid brown in the 3-4lb range. Confidently, I fished the same fly for the rest of the day, landing four more good fish before some mismanaged line saw me break off another when the reel jammed mid run.
Not surprisingly, I was soon back at my tying desk and I tied enough Skinny Brown Nymphs to fill a row in my fly box. Carl was impressed enough to start tying them in a size 14 and championed their success on mountain streams. Since then I’ve fished this nymph often and I’m still surprised at its continued effectiveness. It’s now one of my go to lake flies, sharing space in the same fly box as stick caddis, blood worm and midge pupae.