You will find a great deal of explanation and detail in a series of posts on Just One Week, including underwater photography of flies from the salmon's perspective.

Now I'm home, here are the live links:

The basics - Windows on the World

How and what the salmon may see - Here's Looking at You

Flies above and below water - Eye of the Beholder

Underwater light effects and views of flies - Blinded by the Light

The limitation of the salmon's vision is not its eyes but the water. It doesn't need human levels of vision. It's eyes are capable of differentiating primary colours but we do not know how it's brain composes images.

In any medium black is the most easily detected colour, especially in low light levels. The rapid dissipation of the red portion of the spectrum in spate river water reduces red and orange materials towards grey, diminishing their detectability.

The visual impact of most salmon flies is on the angler: the effect on salmon remains unknown.

 

You will find a great deal of explanation and detail in a series of posts on Just One Week, including underwater photography of flies from the salmon's perspective.

Now I'm home, here are the live links:

The basics - Windows on the World

How and what the salmon may see - Here's Looking at You

Flies above and below water - Eye of the Beholder

Underwater light effects and views of flies - Blinded by the Light

The limitation of the salmon's vision is not its eyes but the water. It doesn't need human levels of vision. It's eyes are capable of differentiating primary colours but we do not know how it's brain composes images.

In any medium black is the most easily detected colour, especially in low light levels. The rapid dissipation of the red portion of the spectrum in spate river water reduces red and orange materials towards grey, diminishing their detectability.

The visual impact of most salmon flies is on the angler: the effect on salmon remains unknown.

Absolutely magical post !

 

Judging by the amount of fly patterns that catch fish through out the season then evidence suggests that fly colour makes not a bit of difference. I do however swear by the theory that if you fish the right size of fly at the right depth given the conditions, then I think you will generally catch fish whatever the fly pattern.

This isn't really anything to do with fly colour but I use lob worms for most of the season and they all tend to be very similar in colour and I do very well from end of April right through until the season finishes in October.

 

Colour does matter........

To anglers that is

 

One would think that the colour that blends in with the background would be the best as no prey wishes to advertise it self. White underbellies of the fish for example.
Personally I think that the only thing that matters is having confidence in what you have on and the most important thing perseverance.
Bob

 

Fly Colours

Live links now inserted in original post above.

 

But perhaps the greatest contrast isn't going to get the most takes?

This, for me, is a key point. Most fly tyers on here will always strive to avoid too bulky a body and silhouette favouring the more attractive lightly dressed fly with a more translucent look about it.

 

This echoes Topher Browne's point about avoiding too much precision. In his words, "you want the salmon to see the fly, but not get too good a look at it". In my words, it's all about presenting an impressionist painting to secure and unthinking instinctive reaction, rather than photographic representation and imitation. Indeed, in my experiments I found that exact representations of salmon prey species were wholly ineffective.

If you follow that hypothesis, in clearer water, where detectability is not the issue, there is virtue in rather ill-defined, diffuse and somewhat dull dressings. Grey, brown and similarly neutral shades (depending on the natural tint of the water green may fall into that category) would be a logical choice.

Conversely, in darker water and lower light levels, where detectability is critical, then contrast and a higher black content come to the fore. The black and yellow spring flies are a product of this line of thought.

If I were younger and had seasons in hand to spare, I would fish one pattern for a whole year, only changing its size to suit the conditions, and observe the result. I doubt that I'd catch many fewer salmon.

 

This is something I have thought and felt for a long time. I even posted a thread about it some years ago.

My own thoughts were not based on any science, just on what I have experienced myself over the years.

It came about after someone posted a thread asking about which flies to use in the back end of the season and someone had replied with "...the Curry's Red Shrimp", which is a very successful and well known Irish Shrimp fly. It used to almost be my own 'go to' fly for fresh grilse. I then started looking through my own records and was reminded of a very successful July and August I'd had about 10 years before that with small Green Highlander hairwings, I'd hooked four grilse in a few hours, one day in July 2002 alone, on colours that most would tell you are spring colours.

Looking at fly tying books after this and seeing patterns like the 'McCormicks Shrimp', almost completely dark claret but for a hot orange front hackle (Autumn Colours you would think), being described as very a successful pattern for spring salmon, it made me firmly believe that 'Seasonal Colours' are something in our own minds.

Another aspect that made me post my thread all those years ago about fly colour was that I had tied a dozen Irish Shrimp flies once for a friend who was trying to raise money for charity. At that time, my bench was in a very dark corner of an old shed with no natural light at all. I had tied all the local favourites like the Green Silk (green body, yellow, orange and badger hackles), Apache Shrimp (Red and Yellow body sections and hackle), Wilkinson Shrimp (Blue, Magenta and Silver body), as well as various other colour combinations of patterns. I went into the shed one evening as it was getting dark outside. The flies were sitting on the bench on a square of sponge. The only feature I could pick up on from any of the flies at all was the Jungle Cock eyes. No other colour of hackle or body material or anything else was identifiable only the Jungle Cock eyes.

This definately made me think about fly colour in the dark or indeed dirty water as we would get here in our spates.

 

Which pattern would you choose ?

 

Inevitably and predictably it would have to be the MCX Dark Shrimp in its Version 2 guise. After all it caught fish on bright summer days when being tested for its swimming qualities, and also in the sombre tones of autumn.

Otherwise a Cascade would be as good as any.

 

Size,speed,depth..Thats all you need to think about.
The rest is up to the fish!

 

i have for 6 years only fished with 2 flies both in black an yellow but more black ,this started as a wager but the first year i caught more than i had for ten years ,so i continued .after 6 years i certainly catch no less fish an tend to think i spend more time fishing an thinking than i do messing about changing flies .

 

Yiv cracked it Michael...it's a Willie Gunn....

 

....although the classic WG has the red and yellow predominating and the black in a lower key. However, like all designs there's huge flexibility and only limited number of ways of skinning a cat to convert it into fly tying materials and then putting them on a hook.

 

Thank you Michael

 

I am sure a black fly in different sizes and weights would catch as many salmon as any other fly over a season.

But there is nothing like changing a fly when you have fished for a bit without a take !

 

I can't add much to what's been said,I agree with most of it,the general theme being ,if you like it,fish it.
For what it's worth ,I might add a couple of observations and a couple of useful flies. Not claimed to be new,very little is, but guaranteed useful.
Mid season on,you may be fishing water which is holding a few fish. The water will have been thrashed with the usual suspects.One or two may have been caught,probably fresh. The pools will hold a reasonable number of other fish which have obviously refused all offerings. A dark claret shrimp,no flash or glitter, can often be effective,right to the end of the season.
If you fish into the evening,with the sun off the water, don't throw them another Cascade. An all red fly, with a sprinkling of glitter,will often produce,right into dark,and right till the end of the season.
Somebody will say,these flies just offer a mostly dark silhouette,an all black fly would do. Hard to argue,as I said,'If you like it,fish it.'

 

This is how my season changes on the Miramichi:







Gary

 

Wouldn't mind fishing there! I see they're all on singles. Your choice,or the river's rules? Do many fall off,or do you find they usually take a good hold?
t.c.

 

Single, barbless hooks only, total C&R by law. Don't lose any more than I did when I fished barbed hooks a few years ago. Just keep the pressure on.
Gary

 

Thanks Gary,
I intend to put a bit of effort in this season using singles. Not before I've got my usual handful of springers in the bag though!
Bottled it already,but takes are too hard come by!
t.c.

 

Almost all my fishing this past few years has been with singles. I haven't see any reduction at all in my hooked to landed ratio. In fact, it might be better than with doubles or trebles.

I've said before on the forum of hooking 12 in a week on trebles and not landing one of them. That was hard to take!

 

I am sure a black fly in different sizes and weights would catch as many salmon as any other fly over a season.

But there is nothing like changing a fly when you have fished for a bit without a take !

The old guy that taught me to fish for Salmon as a kid had a saying when someone asked what his favourite fly pattern was.
"Any colour as long as its black" was always his reply.
Over the years i have probably caught more fish on an all black pattern than any other.
From small Stoats tails up to a big brass tube with either a silver or gold body with a simple black Bucktail wing tied like a Wullie Gunn.
My biggest fish last season (and a few more)was on a simple small black tube.


Now,i always like some black in a fly as i,v never had much luck with flies without it.

 

The fly that I have caught more salmon on than any other fly is similar to the one in your pic but without even the orange butt or silver ribbing. That said, I normally like black plus another colour or colours. More to give me confidence in a fly than a real belief that it makes any difference.

 

All my underwater experiments demonstrate that the black element of the fly is the key to detection. That is also the reason for the RAF painting all its trainer aircraft black, rather than red, yellow or in stripes (1950-92): the black catches the eye and stimulates the part of the brain involved in alerting.

The black is also the only colour that is unaffected by the behaviour of light in water. Once below the surface all the other colours change from what we see in daylight, depending on the muck in the water, the ambient light level and angle of incidence of the sunlight, the depth of presentation, the range from fish to fly, and the angle of elevation at which the fish observes the fly.

 

In Ireland, there would be very few really dark or all black patterns used. Other than perhaps the dark centres of badger hackles or front bodies of shrimp flies, black is not a common colour at all.

Perhaps it's to do with our darker, peatier, water.

Simon Grace is 100% correct. Put any fly to the right depth and cover the fish at the right speed and you stand a chance. Don't overthink thinks.

 

In Ireland, there would be very few really dark or all black patterns used. Other than perhaps the dark centres of badger hackles or front bodies of shrimp flies, black is not a common colour at all.

Perhaps it's to do with our darker, peatier, water.

Simon Grace is 100% correct. Put any fly to the right depth and cover the fish at the right speed and you stand a chance. Don't overthink thinks.

Certainly seen a few people fishing the "right" fly at the wrong depth and not catching, particularly in heavy colder waters.

 

Interesting thread. I can't resist a bit of armchair over-thinking on a lazy Friday morning.

We seem to be talking about visibility in more or less hazy conditions. It's interesting that our focus usually lies in making our flies as visible as possible when it seems likely that salmon as predators are capable of seeing extremely well-camouflaged and tiny prey objects.

The bases of visual perception lie in contrast (between one surface and another) - i.e. edge detection, shape or form and light reflection(sparkle) or colour contrast, and movement.

Although salmon appear to be capable of colour perception (they have 'cones' as well as 'rods' in their retinas) there is uncertainty as to how sensitive the cones are over the course of their sojourn in freshwater. The rods are sensitive to edge detection and movement but not colour.

True black appears to be quite a rare colour both in the marine and freshwater environments, so its merits probably lie in its contrast value - its visibility in hazy water conditions. A suitable mass of black in a fly probably induces a strong shape element - a 'buggy', teardrop or long slim profile which stands out strongly.

There are other means of introducing contrast and 'edges' into fly design. For example, the strong barring in widgeon or teal breast feathers, the effects of bold ribbing on the fly body, the bright tag or ostrich herl butt, the strong marking of jungle cock eyes, using strongly contrasting colours together, e.g. the 'yellow and black' flies and flies incorporating white elements into the colour scheme.

It is also true that colours towards the cool end of the spectrum - chiefly blues, seem to be last longer as a true colour in poor light. Reds seem to lose their colour quality sooner and appear as shades of grey or even black under low light conditions.

Ultraviolet reflectivity (n.b. not the same as UV fluorescence) is another area where strong contrast or 'edge' can be obtained between one part of a fly and another, although we cannot see this property with the naked eye and have to rely on manufacturers' advice. From its ubiquity as a visual signalling property in the animal and plant kingdoms it seems likely that UV reflectivity is a major 'hidden' factor in fly design. It's been noted before that many of the old classic flies incorporated slips of feather with high UV-reflectivity. In the fashion of focusing on minute details of shade and colour in artificially-dyed material, have we lost our way a bit?

I don't have any answers to the age-old questions but if visibility is the primary goal then using contrast and 'edges' seems to be a worthwhile concept.

The Frances fly is a classic example of this - the strong 'blocky' shape with a bold rib. I can't understand why (for me) the red Frances seems to be a better catcher than the black.

 

Tony,
thank you for your thoughtful and useful contribution to this interesting debate.
M

 

If all this scientific stuff were true, how come the salmon hardly ever see my bloody fly???

Paul

 

Same problem as me. At our age we're inclined either to forget to tie it on, or if we do remember, it goes on back to front.

 

would it

HI

would it be the same for sea trout as salmon ?

 

HI

would it be the same for sea trout as salmon ?

I find my memory failures aren't species-specific.

As to your proper question, I don't know because the sea trout's eyes may be subtly different owing to the shorter length of life spent at sea. Nevertheless black is likely to remain the key to the fly's detectability.