Archive for August, 2013

The Cuckoo and the Trout.

August 31, 2013

The Cuckoo Head

I have recently been reading “The Selfish Gene” by Richard Dawkins, a fascinating look at the way genes control us and every other living thing for that matter. But one portion of the book fascinated me in particular, a discussion on Cuckoo’s and their foster parents. As no doubt we all know Cuckoo’s lay their eggs in the nests of other species and then let the hapless birds work day and night to feed their babies. It can get a little macabre, the baby cuckoo will turf the other eggs or baby birds out of the nest so that it gets all the attention and more to the point all of the food. Frequently the cuckoo fledgling is huge compared to its hapless adoptive mater and pater who work tirelessly to feed their grossly oversized intruder; they may even need to stand on the baby to be able to reach its mouth to feed it.

The Selfish Gene Cover

The question that interested me in particular was “why don’t the hijacked foster parents notice the fraud and simply stop feeding the baby cuckoo?” Apparently the bright red gape of the begging bird is a stimulus to the parents, an almost irresistible urge to put food into the open mouth. The larger than average and brighter coloured gape of the baby cuckoo is essentially a “super stimulus”.

It appears that the trigger is so strong that even other birds have been known to “stop by on the way home and feed the cuckoo” giving away hard won food that was destined for their own offspring.

CatchadragonOne would logically think that the fraud would be obvious.

Another interesting if somewhat more risqué example is the fact that simple images can stimulate sexual response in people. That one knows that you are looking at an airbrushed and two dimensional image of a man or woman that you will never meet and who quite evidently isn’t available to you, the mating response can still be switched on.  It doesn’t seem to matter that the subject is well aware that it is a fiction.

It seems that there are key triggers in nature, stimuli which are so powerful that they become, according to Dawkins, near addictive in their allure and that got me to wondering, are there such key triggers in feeding behaviour too? In particular are there such triggers in terms of the feeding behaviour of trout?

To my mind the art of fly tying is about caricature, there are those who will say “this is what the trout think” or “this is what the trout see”, actually I don’t have a damned idea what trout think or see but I do figure that, as anglers we cannot possibly actually imitate an insect, we can only represent it in some recognisable form. So we pick on key indicators, essential elements of real insects which we believe are representative.

Perhaps this is the key to why fish don’t seem to be overly bothered by the hook, after all, much like the oversized cuckoo, the hook sticking out of the rear of your delicately fashioned fraud should be a dead giveaway, but thousands if not millions of captured fish seem to show that it matters not a jot.

Trout and FlyDecision time.

I suspect then that if key triggers can be imitated or emphasised they can “overpower” what one might imagine to be an obvious flaw in the design.

Put simply then if a dragon fly nymph imitation is the same shape as the real thing, moves much like the real thing, is the colour of the real thing then the fact that it has a hook sticking out of one and nylon tippet sticking out of the other doesn’t affect the response of the fish to what they see as food.

Equally a mayfly pattern if it moves (or more likely doesn’t move), creates a similar pattern on the water surface to the real thing, is the right colour and size (perhaps larger could even result in a more pronounced response), the fish will eat it. It could very well be the reason for the success of cripple type patterns, it would be simple to imagine that the fish instantly recognises the struggle of a stillborn fly as a easy meal and can’t resist.

It seems to me that the idea adds credence to much that we already know about trout feeding behaviour, and offers explanation to much that we witness when on the water.

In tying and fishing flies then it would behove us to think in terms of key stimuli, the pattern the hackle makes on the water, the eyes of a dragonfly nymph, perhaps the pronounced tails on a spinner pattern, the classical segmentation of an ant pattern, the erratic movement of a corixa or the manipulated “escape” of a nymph pattern fished to create and induced take. Could it be that they are all “key triggers”?

We know that we cannot create an exact copy in much the same way that a baby cuckoo cannot, at least for long, look exactly like a baby wren, but we can, as does the cuckoo, overcome that apparent flaw by carefully designing our flies and fishing them in a manner to override the obvious in favour of key stimuli which will trigger we hope the required response.

TroutandHopperHow much of the feeding response is pre-programmed into the fish?

It could be that we can use the fish’s own genetic makeup to help us deceive it. In effect causing the pre-programmed genetic makeup (what Dawkins refers to as the extended phenotype) not so much to allow us to deceive the fish but to afford the fish the chance to deceive itself..  Perhaps that is what the wrens are thinking, “jeez look what good parents we are, look how big our baby is and how wide his mouth gets when he is hungry”.. ?

It has been long recognised that deliberate overemphasis of some elements in the way we tie and fish flies can be effective and Dawkins discussions on the extended phenotype (that is the effect that genes have on the world around us and our interactions with it) might offer a clue as to why such machinations work on the water.  If the fish’s genetic makeup program it to grab anything that looks like food, and furthermore determines what criteria it uses to recognise such food, then we can exploit that in very much the same manner as the baby cuckoo exploits the wren’s response to gaping beaks. It’s still a con, but perhaps a con now with a scientific basis.


Should tippets float?

August 13, 2013


Floating tippets.

Ed Herbst recently forwarded me some information on floating or sinking tippets and frequently when Ed takes the trouble to do something like that it is worth reading. Ed is a newsman, perhaps more accurately now an ex-newsman, but he still has the drive to seek out a story,  these days related more to fishing than to the vagaries of politics and the machinations of those in charge of public funds.

The mail primarily consisted of a number of different viewpoints on floating leaders, floating tippets and fluorocarbon, the consensus apparently amongst the “new wave” was that you were better to float your leader and tippet rather than follow the age old rule that you should endeavour to get the tippet subsurface as far as possible. Much of the discussion focused on views from Peter Hayes, although there were extracts from other sources as well and various reasons for the apparent change of heart on this matter mooted. I thought it worthy of some further discussion.


It would seem that in his book “Fly-Fishing outside the box” Peter Hayes boldly claims in Chapter six to know “How fish see the leader”.. Now I am always willing to listen to an argument, particularly a fly fishing argument and equally happy to defer to anyone who can provide some logical hypothesis no matter that it might go against my own beliefs. As we shall see Hayes makes some good points, some more than worthy of consideration, but off the bat I have to say that I try hard in my own writing not to say things like “how the fish see the leader” or “the fish think such and such”. No matter what we know, how well we research, it isn’t possible to know exactly what a fish sees or how it interprets the data. “How fish see the leader” therefore is in my opinion just a little too bold a statement. What we can confirm are certain scientific facts about refraction, light, opacity, which are scientifically proven.

So anyway the idea put forward by Hayes is that all the guides and tutors are wrong, that they have foisted upon an unwitting angling public the idea that the tippet should be sunk as it is supposedly then less visible to the fish when in fact it is far less visible when floating in the film.

There is some logic to the argument, according to Hayes’ own pictures it would seem that in the mirror the sunk tippet shows up twice, as indeed does the hook whilst the floating tippet is only visible as a single strand. Ok score one for the floating tippet if you like, but that is a pretty narrow consideration of the overall fishing situation.

My experience of fish which I believe are refusing a fly due to the tippet don’t refuse it in the mirror, they frequently approach the fly with all confidence, and hesitate at the last moment, the moment that the fly and the tippet are in the “window”, it appears to me that the failing occurs at this point of close inspection. (The terms “mirror” and “window” refer to the view of the fish related to the effects of light diffraction and reflection inside and outside of the Snell’s circle, for more information on these elements of trout vision I would point you to Goddard and Clarke’s “The Trout and the Fly” or a number of other publications on trout vision)

I am not sure that what is visible in the mirror is of that great an import, not with small flies and 7X tippet anyway, it is the close up inspection that seems to me to be more problematic. My observations suggest that a possible food item in the mirror indicates “worthy of inspection” to the fish, a close up view of that item in the window is more a case of “should I eat it or not”.. (and again I am wary of suggesting that is what the trout actually think, it is what I imagine the trout think which may well not be the same thing)


In my experience, refusals on flat water are virtually assured if the tippet is floating. Here a trout having purposefully approached the fly (one imagines having picked it up in the mirror) turns away at the last moment.

Where I fish there is a second and to me far more critical problem, the shadow of the tippet on the bottom of the stream. In Hayes’s argument the peripheral effects of such are less important than the fly on which the trout should by now have focused its intentions. To be fair, Hayes is primarily I understand considering fishing in the UK where bright sunshine isn’t an overly problematic issue for most anglers, they simply don’t have enough of it. Plus almost every fly fisherman in the UK will tell you on a sunny day that “things are too bright”.

Here on the Southernmost tip of the African continent clear blue skies and bright sunshine are the norm in summer. If fish didn’t feed during the brightest of days they would starve, if fishing guides didn’t fish on such days we would starve too for that matter. So we fish a lot in clear shallow water, to (at the risk of falling into that anthropomorphic trap once more) “educated fish”, on catch and release streams, in the brightest of conditions you might imagine.


In clear water, with little weedgrowth, bright sunshine and clear skies, shadows are the enemy, including the shadows of floating tippet material.

In such circumstances I assure you that a 7x tippet when floating will throw a shadow on the stream bed that looks like an anchor chain for a luxury liner. Additionally, any movement of that line, either resulting from casting or perhaps drag will create a semaphore on the bottom akin to a lightning bolt.

So is the hypothesis of Hayes , that a floating tippet is better than a sunken one reasonable or not? If one were to offer advice, which way should you go? This isn’t about proving who is right or wrong, but about considering all the various factors at play.

Firstly Hayes quite categorically states that no matter if the leader sinks or not, if you land it on the fish’s head or in its window it is likely to scare the hapless creature half to death. We are in agreement on that front. Hayes also promotes the idea of casting at an angle across to the fish rather than directly upstream at the fish, something that I hold to be absolutely correct. Fishing directly up to a fish unless the geography prevents any other option is generally in my opinion a very poor option.

The piece also states that the sunken leader is more likely to drag than the floating one, based on additional surface contact with the water, you can’t really argue with that either, I am pretty sure that is true, although the degree to which the two differ I can’t imagine to be that gross, not over the duration of the average dry fly drift.

Finally there is the suggestion that sunken tippets create unnecessary “slurping” noises on pick up that are likely to spook fish compared to the supposedly cleaner pick up of a floating leader, for my money that is more a function of poor casting than sunken lines.

FishWindowThe “window” defined by Snell’s circle represents the area where the fish can see a clear image against the sky, outside of that the fish sees a reflection of the bottom in the mirror and disturbances to the surface film show up as a distortion of the mirror.

So for what it’s worth my thoughts on these concepts:

The floating tippet is less visible than the sunken one:

Yes you may well be able to show that there are “Two tippets” in the mirror when sunk, and only one when floating but to my mind that isn’t a critical issue. There are also two hooks in the mirror and that doesn’t seem to bother the fish that much. In fact with a semi floating fly, emerger or Klinkhammer there are two abdomens as well.  To my way of thinking the appearance of a potential food item in the mirror is simply the first trigger to the fish to investigate, fine analysis comes later in the drift when the fish is on the verge of committing. I don’t believe that the image in the mirror is that critical. We have all seen trout approach items, flies, artificials, seeds etc which they have obviously noticed in the mirror , only to turn away once the item is in clear focus in the window.

The sunken tippet will be in the way of the trout taking the fly:
On a straight upstream cast one supposes that could possibly be an issue, however both myself and Hayes seem to be in agreement that such as cast is already your worst case scenario, irrespective of the floating or sinking properties of the tippet. Most anglers would opt for a cross stream cast and the very best anglers (Pascal Cognard for one) would opt for a curve cast on every presentation, keeping the visibility and the potential for interference from the tippet to an absolute minimum.

The additional shadow on the stream bed is less important than the upfront visibility:

That may be the case in cloudy and dull conditions but I seriously doubt the validity of the argument on bright days in clear water. It is pretty much a given amongst fly anglers that the clearer the water, the brighter the day and the less current there is to hide the tippet the more difficult it is to catch the fish. Or as one local wag at the World Fly Fishing Championships in France years back said to me whilst gazing over a flat calm filled with rising trout.. “ C’est Impossible” It is “impossible” because of the tippet and for my money I would give up a few of my prized rods for someone to come up with a fine tippet that consistently sank below the film.  Not only is it less visible, but as or more importantly fish are generally far less wary of things under the surface. If you are a wild trout in a stream, nearly all the bad stuff in your life comes from “up there”. I would suggest that if you are a trout, two things that you are always going to be careful of are surface disturbances and unexpected shadows on the stream bed, both are likely to be bad news if you are a tasty trout in clear water.

I equally have to add, that on stillwater, where there is plenty of time, I have frequently watched trout swim up to an artificial and turn away, over and over, until at some point the tippet finally sinks below the film, a trout approaches and eats the fly with apparent confidence. To my mind the floating tippet isn’t a good idea it would a take a lot to change my mind.

Floating leaders are less prone to drag:

It makes sense to me that this may indeed be true, but I am less than convinced that it really is a significant factor. Something that would easily be overcome with a few inches more tippet or a slightly longer leader, actually to my mind factors associated with getting slack into the leader, the construction, the length, the use of fine soft nylon are all more important that the possible additional drag from a sunk leader. Bear in mind that as a rule I never fish leaders shorter than 14’ and frequently in the 20’ range even on small streams, specifically to reduce and/or delay the onset of drag.

Floating leaders are more prone to making noise on pick up:
Done poorly that is undoubtedly true, but a slow draw, possibly combined with a roll cast pick up reduces any noise to virtually nil, whilst again on my home waters and the clear bright conditions under which we fish, dragging a floating leader across the surface may well be silent but the abstract art of shadows it creates on the stream bed is likely to spook every fish for miles around.

And then here’s an idea of my own:

Additional drag on the sunken leader may well assist hook-ups:

For some time now I have been experimenting with striking angles when hooking fish. It seems that, particularly when dealing with small fish, a low strike angle provides a better hook up than one of a more upward trajectory. I suspect that this may well be due to two things: one that the smaller fish, if lifted don’t provide much by way of stability, tending to move with the strike and not allow sufficient pressure on the hook, (rather like a boxer riding out the punch), and secondly that the low angle keeps the leader and perhaps line in the water, offering additional purchase and a more direct strike pressure to the hook. Worth thinking about perhaps.


This discussion was prompted by Ed’s correspondence, I have yet to read the entire book but shall look forward to it, anyone who thinks as carefully about a subject as Hayes has obviously done is worth reading. The book is available from Coch-y-bonddu books
or from Netbooks on the link Fly Fishing Outside the Box

I must admit that I always enjoy that people are thinking about things in the fashion that Hayes explores these concepts in his book, we are not really at loggerheads in terms of the discussion. There is a great deal with which I agree written there and of course circumstances vary from place to place. There may be a case in dull conditions where perhaps a floating leader isn’t such a disadvantage; I hesitate to suggest that in my mind it would be an advantage. But for my money on a clear, shallow, slow flowing pool on a Cape Stream, with the sun blazing out of a blue sky and a large trout in my sights, I would willingly slaughter a neonate and anoint the tippet with their blood if I thought it would assist in punching the nylon through the surface film.

As always comments are most welcome, and I am always open to suggestion and discussion, one thing I have learned from years of fishing is that much of which we were once sure eventually makes way for a different perspective, frequently involving eating quite a bit of crow washed down with a jug of humility. If you can prove to me that floating tippets are an advantage I will willingly swallow my pride, but you will have to prove it on a sunny day in the Cape, when the water is low and clear the fish have all been caught before, and the average Northern Hemisphere angler is telling you that it is “too bright to fish”.


Books are also available directly from the author at