Wednesday, 16 October 2013

Crash! Bang! Pluck! The dynamics of a take

I apologise for the delay to this post, which is long overdue.  Unfortunately 10 days ago our 93 year old neighbour fell and broke her right leg very badly.  As a result I've spent much of the intervening period visiting the hospital rather than thinking and writing.  In between visits I did manage to fit in a successful day on the Ure last week, which will form part of a future post.

Iceland film - the instant of a take
Last January in 'Revelation' I looked at an example of a salmon taking a fly live on a film made in Iceland.   If you haven't viewed it before I strongly recommend doing so, not least for its remarkable insights and excellent underwater resolution.  Of course this is only a small sample of one group of fish, in one river, on one day, so we have to be careful not to draw too many inferences.  Nevertheless it is the best illustration of sub-surface taking behaviour that I have seen.  It also provides some confirmation of my own observations of the angle at which salmon approach flies; the sort of distances they can cover in moving to the fly; and the lack of indication to the angler of the fish taking the fly into its mouth.

There is a lot of good footage of salmon taking a variety of flies fished on the surface - bombers, hitched tubes and giant caddis - with especially good examples from Newfoundland and Labrador where dry fishing is a widely used tactic.  However, all of the film I have seen is taken from or near the angler's perspective: I haven't found any underwater sequences of surface takes showing approach angle and so forth.  In addition, the small number of salmon that I have caught in the UK either on the surface or in the surface layer does not give me adequate evidence for analysis and discussion.

Equally, I haven't equalled Hugh Falkus' endless hours of observation from elevated points of fish behaviour in clear water responding to a variety of baits and lures.  Nor is my armoury as broad as his: worms and prawns are not part of my repertoire.  Accordingly, this post only examines the dynamics of sub-surface takes whilst fishing with sunk flies.  

In thinking about takes there are 2 cardinal points we must bear in mind.  

  • First, there are plenty of theories but we don't know what prompts a salmon to take a fly: every take is aberrant behaviour that currently defies explanation.  I have difficulty accepting the 'induced take' as anything other than good fortune based on getting the fish's attention.
  • Second, the way in which an adult salmon takes a fly is markedly different from how it takes prey at sea, even though the fly may emulate a marine species.  Like other predators the salmon attacks at high speed - 3-4 m/sec is typical - as it scythes through a shoal of sand eels.  I've watched salmon feeding in the surface layer and there is an audible hiss as the dorsal fin cleaves the water.  If salmon hit our flies at that speed sprained wrists and broken rods would be commonplace.  In addition, the salmon's mouth and throat is designed to trap and swallow prey fast enough to make room for the next sand eel, yet I have never hooked a salmon in the gullet.  In sum, it's doing something abnormal prompted by factors other than hunger.

Thus every take is different and unique to the fish and the circumstances.  Nevertheless they appear divisible into some 'classic' groups.  This post looks at 3 broad types - 'Against the Fly''With the Fly'and 'Minimum Shift' - that have been the commonest in my experience and are therefore most easily described.  Beyond those is the realm of  the random, usually involving later-season cock fish, which includes extreme cases such as the  'Headlong Charge' and 'Surface Slash'  While these make for amusing anecdotes they are not amenable to analysis beyond noting the power of testosterone.

Crash!  Against the Fly

Take - Against the Fly
You're fishing from the right bank with your fly tracking from left to right.  The diagram shows in 3-D the track the salmon might follow from its lie at A to a take at T, before turning away at D to return to A.  Whether the fish takes by interception as shown here (a likely scenario with a slow moving fly) or follows it (the converse case) matters little.  The key factor is the direction of turn after the take, which is opposite to the movement of the fly.  This increases the relative speed of fish and fly and so makes it harder for the fish to eject the fly.  The tension on the line L comes immediately into play, usually causing a good hook-hold towards the rear of the salmon's jaw.  You probably won't feel anything at T, but as the fish turns D-E, feels the drag of the line and reacts, its acceleration will leave you in no doubt.  The 'crashing take' is at E not T, when your fish is usually well hooked.

In this scenario you have to do precious little, beyond smoothly lifting the rod and leaning back to get the hook all the way home.  Never do anything hasty or violent, and as always, ensure your drag is on a sensible setting.  Barring bad luck you will land the majority of fish that take like this.  You'll be able to identify them by virtue of the hook often being in the side of the jaw opposite your bank - i.e. right bank, left jaw.

Bang!  With the Fly

Take - With the Fly
You're still on the right bank.  The next fish comes up from A and takes at T.  At D it turns with the fly and swims parallel to X.  You are even less likely to feel the take.  In this case the relative speed of salmon and fly is much lower, so the fish has more time to eject it, largely untroubled by the line tension.  Three options follow: you don't hook the fish at all and feel nothing; or you get a weak hook-hold near the front of the right jaw which soon comes undone (bang-bang, gone); or if you're lucky the fish turns and dives sharply at E, giving you a strong take and a good hold in the upper right jaw. 

The simple fact is that if the fish turns with the fly the mechanics are much less favourable, but there are no sure fire ways of changing the odds.  Just observe the basics.  Keep a good working tension between you and the fly.  Use the rod as your first shock absorber by holding it upstream of the line.   Keep couple of feet of slack line as a back up to the rod (which reacts far faster than you ever can).  And again, don't strike or do anything hasty.  If you've missed, you've missed, and only one per thousand comes back for a second try.

Over the years I've heard a lot of advice such as giving the fish slack to run back to its lie before setting the hook.  This is probably more about stopping inexperienced anglers doing hasty and violent things than anything to do with hooking fish.  The salmon will only take the fly back to its lie if it has failed to eject the foreign object from its mouth; and the fly will only stay in there by virtue of the hook.  In any event the drag on a salmon fly line alone is more than enough to start the process of setting the hook.  I therefore suggest that the hook hold does not improve  much with delay.

Pluck!  Minimum Shift

Take - Minimum Shift
We now enter the realm of the gentler take, or more accurately, turn away.  Indeed, the salmon may not have to turn at all.  The minimum shift take occurs most often when the lateral movement of the fly is very slow and close to the fish.  This is the case at the dangle: lateral  movement has stopped and the fly may be sinking. Hence in this diagram the fly is shown as a point rather than a track.  The Minimum Shift take is also common in ambush fishing and when working a fly deep and slow in response to cold or dirty water, when the salmon reacts to something almost directly ahead at short range.  You get the same condition when a curious salmon has followed a fly over a considerable distance in quiet water, only taking it into its mouth when it starts to move directly away.

Minimum Shift Take
Hen fish from low slow water
Blue Charm #14 front centre of jaw
Dalnahoyn Pool Tomatin
 13 September 2010
Here the fish merely inclines its pectoral fins to rise gently to B, applying the minimum lateral movement.  It takes the fly into its mouth at T before reversing the pectorals and sinking back towards C.  Clearly without lateral movement there's not a lot of force in play.  As a result hook holds tend to be towards the front of the jaw and inadequately sunk.  The salmon gives a couple of shakes of its head to get rid of the fly; you feel the consequent pluck, but it's already gone.  All too often it stays on for 5-10 seconds before the hook hold gives way.  But if Murphy's looking elsewhere, sometimes they stay on.


It may seem strange that you will detect the merest fragment of leaf, weed or grass upon your fly, yet incredibly you feel nothing when a salmon takes it into her mouth.  It's simply because in most cases the first stage of the take is towards you and slackens the leader.  Which way the salmon turns from the take is the determining factor in what you feel thereafter and how soon.  Only then do you become an active participant.  There's no magic or tricks, just a few basics to observe.  Most salmon hook themselves without your help, so all you have to do is avoid upsetting that happy situation through haste and violence.

Hopefully by the next post some more salmon will have hooked themselves for you and me.

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