Grayling with the flow

Malcolm Greenhalgh says some fine tuning will help us get our hooks into grayling

When we cast our fly to a trout or a grayling, we want the fish to take the fly in its mouth so that we can set the hook and then play the fish to the net. That statement sounds so obvious that it needn’t be said. Yet, it is not that easy, especially when it comes to the dry fly and the grayling.
I stress, the dry fly. If you fish a very heavy Nymph on a short line, ie go Czech-nymphing with the fly deep under the rod tip, often the fish take the fly so powerfully that they set the hook themselves. Bang! The fish is on. But if you find some grayling taking pale wateries at the surface and cast your dry fly, in standard fashion, up and across the stream, you will frequently get rises but, for some strange reason, the fish are not hooked. I struck too early – or too late – we say, and we try to slow down (or speed up) our reaction time.

Yet the problem is not one of timing. It is all about the mouth of the grayling.

The buccal problem
The mouth of the trout is terminal; in other words, it is at the very front of the head. However, the mouth of the grayling is inferior; it is on the underside of the head and the front of the head (or snout) protrudes.
So, when a grayling rises up a short distance to take a weighted Nymph and returns to the bottom as it takes the fly, the point of the hook can go nowhere other than in its jaw. Hence, ‘Bang! The fish is on.’
However, when the grayling rises to take a dry fly that has been cast upstream, often the snout breaks the surface, hits the tip of the leader close to the fly, and this knocks the dry fly away from the mouth. This does not happen with trout, because the mouth is terminal.
Other differences between trout and grayling when they take the dry fly
More often than not, a trout which is feeding on a hatch of duns lies just beneath the surface or, as it was poetically put years ago, ‘on the fin’. This means that the trout has simply to lift its head to take a fly from the surface. Thus, we can cast our dry flies only a few inches upstream of the trout and be confident that the trout will see it and have plenty of time to grab it.

More often than not (from my experience, almost always), a grayling that is feeding on a hatch of duns lies on or just off the bottom. This means that the fish has to see the fly approaching and swim up to the surface to take it. Sometimes, in deeper, turbulent water, the grayling will be vertical – or almost falling over backwards – when it takes the fly. This means, of course, that the snout breaks the surface and is more likely to knock the leader in a cast made in an upstream direction.
Thus, we must put the dry fly that bit further upstream of a grayling to give it time to see the fly and then swim up to intercept it. This automatically gives rise to a problem that is greater in dry-fly fishing for grayling than for trout: drag. The further the dry fly has to drift downstream on a straight line the more likely is the onset of drag, and despite many people saying that grayling are more stupid than trout and that they will take a dragging fly, grayling will usually ignore a dry fly that drags.

Find out how Malcolm solves these problems in the January 2008 issue of Fly Fishing and Fly Tying magazine.