Perhaps just to get a discussion going I will put forward the proposition that despite fish perhaps being able to see leaders they are too thick to connect the danger with the artificial fly! In other words their saving grace is their spookiness and thus after seeing the leader they hesitate to feed on what appears to be a "real" fly beside it! For in reality no fish has been educated to link a leader with a fly (I hope!)
Having said that I have caught fish when my leader landed in a heap and the fly in the middle. Perhaps they were the fish that were bottom of the class?

After years of coarse fishing I believe that how a baited hook behaves is much more important than the visibility of the hook length. Soft pliable materials act more naturally, especially when compared against the behaviour of free offerings in ground bait. Stiff materials can cause anti ejection and self hooking scenarios.

Does this follow for fly fishing? If it did we would use the softest leader material possible and I could never bl@@dy cast it. I use riverge fuorocarbon, not because I believe for one minute that it is invisible, but because I can fish two flies on the same leader for most of the day.

I think they do, and I suppose they can learn to avoid flies attached to lines if flies with visible tippets have caused them problems. For a lifetime I have read and heard about gut-shy fish, but I think unnatural movement matters more than unnatural appearance. I also feel that fish have a very simple philosophy regarding movement, at certain times, which goes ---' You're moving and you're smaller than me, I can eat you: you're moving and you're bigger than me, you can eat me -- I'm offski!' A 'dickybird' flying over the water doesn't usually scare them -- martins, swallows etc, but an aerialised line can. According to one video display, they appear to see a line reflecting bright light as something like a neon sign.
Although I like my tippets to lie sub-surface, I have long ago lost count of the number of fish that have taken a dry fly atttached to a leader that stood out like a little cart-rope. I'll bet a lot more anglers could say the same.
TC

Aye Terry,Ive been surprised many times by fish taking a fly in a flat calm,with my leader lying like a ships hawser on the surface film.However most of them seem to realise their mistake immediately as their act of taking ,moves the floating leader on the surface,causing them to bolt off in panic....sometimes managing to hook themselves in the process.

I'm sure it may have been Arthur Cove or was it Dick Walker..? who made the statement that fish can always see our leaders but simply do not associate them with danger......untill that fish has been caught and released.It then becomes necessary to use lighter leader material before that particular fish is likely to be fooled again.

Aye, Jimmy, If they can see little midges that we can barely distinguish when standing in the water, downstream, in their feed lane, then they can see our leaders. Have you ever had trout feeding on wee midges take a knot in your leader? TerryC

Was watching Henry Gilbey sea fishing and he was using red nylon sraight to the hook!!
He was catching fish no problem.

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I can't recall trout doing that with any certainty Terry, but Ive certainly had small roach come up and peck at the knots and leader in general,often enough.

Hi,Maharg, and All,
Re leaders, I think it was of your countrymen who caught a salmon on a fly tied directly to a salmon line. It might have been Peter Anderson. Which reminds me that one brave soul vowed to fish the same fly all season, I believe it was a Stoat's Tail. Anybody able to confirm above? I am also sure that it was said the catch difference at the end of the one-fly season was negligible. Stoat's Tail, a magic fly. But the Stoat family are all good,, Stinchar, Thunder and the Silver version. TC

Using Steelhead as an example, it's far more important how 'the bait' is presented (be that a fly, roe, bobber, etc) than the size of the leader/hook it's attached to.

The exception 'to the rule' is during periods of very low water flow (especially if it's really cold water). Here, for me anyway, how light/small can you get away with. That said, fish with one fellow who (year-round) with flies the size of dead birds (Intruders) and 10-12 pound Maxima leader material; he does very well regardless of the water conditions.

Darn him.

I'm sure the manufacturers and aficionados of fluorocarbon and other expensive lines would have us believe that line translucency and a few thou' in diameter can make all the difference - but I'm yet to be convinced.

Throughout this season, on our heavily fished catch-and-release water, I have been conducting a little experiment of my own. I have been using, for sub-surface fishing, 8lb Maxima "Ultragreen" line and comparing my results with our resident "top gun" who swears by 5lb Mamba fluorocarbon - my catch-rate has been comparable.

I'm not convinced that a trout, that can be deceived by, a sometimes gaudy, artificial with a hook-bend protruding from the back, can be put off by line which, in all probability, it hasn't the intelligence to associate with the fly.

I do agree with fossil-fish that "presentation" can be critical and sometimes a "softer" line is better as it allows the fly (or bait when coarse fishing) to behave more naturally.

I use 4lb Maxima "Ultragreen" for small dries (18s) and found it to be perfectly satisfactory - and a great deal cheaper than most.

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How poor a thing, sometimes I find,
Will captivate a greedy mind - Isaac Walton.

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