How do you do it then? Do you make the nymph jig by moving the rod tip; or is it movement only imparted by working the line with fingers??

Also, what depths do you have success, and how do you find it??

As I see it, you have two basic choices. When fishing the moving wet fly/nymph, downstream on a slack line, you permit the fly to pass you and continue on at depth by feeding slack into the system by tracking. When you check the rod, the flow of the current acting upon the extended line lifts it, and the fly; and this upward movement is termed, 'the induced take'.
When fishing a static fly, in still water angling, the fly lies innocently on the bed of the lake, pond, reservoir until it is given a lift by raising the rod, in the hope that a fish will be attracted by the upward movement. In clear, small still waters, the stalker will perform the lift when a patrolling trout is seen to be approaching the resting fly.
In river fishing it is said that the upward lift of the fly simulates the movement of an ascending natural nymph. Cheers, TerryC

Tricky. There's no prescribed formula for inducing a take. One must be able to either see the nymph (and the target trout) or at least have a pretty good idea where each is in relation to the other, The fly is allowed to drfit towards the fish until, at the right moment (and only the chap holding the rod can decide when this is) the fly is made to rise up in the water. How this is accomplished is perhaps immaterial; one can simply raise the rod tip, or the line can be drawn back by the free hand.

However, there are some things to consider, which might help with the final decision. Obviously, in moving water the slack line must be constantly taken up as the fly and line drift back towards you, otherwise all the hauling and rod raising you can muster won't shift the fly an inch, and if the trout takes dead-drift you won't hit it anyway. So I suppose which method you use is determined partly by current speed; in slow water you can add an extra pull on the line between drawing in the slack, whereas in faster water you may not have time, so raising the rod point might be best.

I think you get a sharper movement of the fly by pulling directly on the line, but you can move more line with the rod than you can with the free hand.

Two good answers already - just to note that it can be worth imparting an "induced take" type movement when czech nymphing (especially after you have already caught several grayling from a shoal). You can do this just by raising and lowering your rod tip by 6 to 8 inches during the normal drift/tracking process.

Interesting stuff. Half way through a book by Oliver Kite on this subject. It only really goes into any depth about fishing chalk streams, which is really good.

How about fishing nymphs on stillwaters though?

Don't forget you can induce takes on the nymph when fishing Reservoirs and still waters.

Always remenber to hang...even your nymphs, and drop them back 4-6" by dibbling the rod....you'll be amazed what a difference it makes.

Also:-
Brightest Nymph on the top dropper i.e. Pearl rib/back or Fluorescent red head. This will attract and pull the fish to you flies (also catches the sun better), again doubling your chances as they must swim by the other natural flies on your cast twice.

When you’ve left the bung for say 30 seconds so the flies are vertical, figure of 8 about 3ft of line into the boat, then stop, this does 2 things first it raises all of the flies in the water column just as the natural buzzer does, also the bung causes a big disturbance on the surface, this again attracts the trout to your flies, this slight movement can make all the difference and induce the take.

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Fordy - considering your location, I suspect that you're referring to chalkstreams and sight-nymphing? Basically, a good approach is to spot your trout and cast maybe 6-8 feet upstream of him (the depth and pace of the water may influence how far upstream you cast as you want to give the fly time to sink to the trout's level) and let your fly dead drift down towards him. You should ideally aim to have the fly drift around 2 feet to the side of him rather than straight down his nose. That way you can see if he moves to take your fly. If the dead drift approach doesn't work, then you try an induced take. Basically the approach is exactly as above but this time, you can let the nymph drift in line with the trout. When the fly is a foot or two upstream of the trout, lift your rod slowly but steadily so that it pulls the fly away and looks like a nymph swimming. You only need to move the fly a couple of feet and it should be a steady draw rather than a fast jerk. All being well, you will see the trout move to the fly. You may not always be able to see your fly so obviously it's a case of judging where your fly is likely to be and watching the fish. It's a thrilling way of catching a trout and when done well, about as skillful as fly fishing gets in my opinion.

Hi Alwyn/Rob

Can't wait to give this a try on a few of my favourite chalk stream locations, which thus far I've desecrated using a stick float and five pints of maggot.....

At the moment though I'm trying to learn my 'trade' at the local stillwater venue, Meon Springs. It's about 10-15' deep and very clear. People seem to catch orn largish white or black lures at the moment, which is fine.

I fancied giving a nymph a go though - probably after reading the books I've mentioned.

So Rob - am I assuming the cast is suspended from a floating line in your explanation? I can see how that would be deadly in a reservoir - but I'm not sure I'm allowed to use a multiple fly cast at Meon Springs. I'll check that out.

On the catch and release lake there, you can see a few big old smart fish cruising about - and I'd love to get into some of that!! I thought a bt of cunning nymphing may do the trick.

I think the stillwater stalkers use this all the time.
Check out Peter Cockwill's stillwater fishing book at the library where he uses his "where all else fails" stalking bug to target big fish. I think he actually lets the bug sit on the bottom and waits till a big fish comes near and raises the tip to make the bug rise if front of the trout.
Incidentally, Peter showed me how to use this method for Alaskan sockeye congregating in big shoals. A short upstream cast was made with a short Teeny mini-tip and a mend upstream to slow the drift. When it was about level, then a slow lift was made with the rod tip, and you could see these salmon coming up to take the Teeny nymph. Very exciting! Sometimes they took the nymph deeper and you couldn't see the take, but you could feel this very slight tension on the fly. A lift, and you were into a pocket rocket!
The Americans reckoned that sockeye could only be foul-hooked, but Pete showed that this wasn't true!

Meon is a good water to practise the induced take, though you'll be better off waiting for some warmer weather. The C&R stretch is a good place to practice the technique. Successful flies (for me) include PTN, Walker's mayfly nymph, white chompers and hare's ears. I expect stalking bugs would work as well, but for some reason I can't get trout to take them.

As Stevel says, the trick of letting a nymph lie on the bottom (at Meon this is best done in the small clearings you get between the weeds) and lifting it up when a trout swims past is a good one, but you need patience - and a fly you can see. I tie Walker's mayflies up with white ostritch herl, which makes for an easily seen fly.

Trout move between the weeds, so you lower your nymph onto the bottom (and it's always deeper than you think). The trout then refuse to pass through the opening. You fidget around for five minutes, then lift the fly out and try somewhere else. Immediately the largest trout you've seen all day swims right over where your fly used to be, as if looking for a tasty snack. That's what happens to me anyway.