Found a interesting thread in reference to leader diameters...

[Slick Rick]

I've been going back and fourth on whether or not to use a flouro leader on my flipping stick (currently running straight braid) and came across a interesting post to a thread of similar discussion on another forum. I did not write this... and a link to the original poster is at the bottom.

What do you guys think?

Somewhere along the line (pun intended here) I read that science has determined that the fish brain is only really capable of comprehending the positive/confirmatory aspects of its potential prey (real or fake). That is, presuming that they happen to be feeding selectively at the time, they essentially go through a mental (but non-cognitive) check-list when coming upon the next potential forage item. Whether its a #3/0 streamer or a #32 midge pattern in approximate order, as best as can be determined the fakes we often employ have to be about the "right" length, the "right" shape, the "right" behavior, and finally the "right" color (although an awful lot of fish have been caught on chartreuse lures over the years, and other than goldfinches there's precious little in this world quite that bright, so go figure). If a fish is still feeling safe, once these criteria are satisfactorilly met, the game's afoot more than likely. Visually speaking, the leader is no more important in tipping off the fish not to bite, and the same goes for the big steel hook sticking out of the stern of any dry fly... no natural has such a feature and yet fish will take a well presented fly with utmost confidence that it has found the real deal.

Fish don't "know" what a leader is, only what it does to the presentation of the lure/bait. Provided its presence/absence does not impair the behavior of the thing being offered on the hook, it is largely irrelevant what we use, at least from the standpoint of getting bit goes. As has been noted, there might be other reasons (like landing/handling) for making a special choice.

That fish seeing leaders doesn't really matter was demonstrated pretty conclusively back in the 50's or 60's when Japanese beetles were affixed (presumably with glue?) to various diameters of tippet and then set otherwise freely adrift on a current thread leading to some very fussy spring creek brown trout that were feasting on the then new (?) outbreak of these invasives. The PA flyfishers involved (I forget who, but Joe Humphreys comes to mind; but could've been Marinaro or more likely the PSU legend George Harvey... they all run together after a while) thought that by recording what percentage of each beetle's associated tippet diameter got rejected, they'd discover the threshold of tolerance for tippet diameter (via visual detection) those well fed, supposedly cagey browns in that clear water had.

I imagine that after glueing all these refrigerated beetles to a bunch of ~20" strands of various diameters, on the stream they had a discussion about which tippets to test first. Someone was apt to have said, "Let's try the really fine tippeted beetles first; we 'know' they'll get eaten, then we switch to the next thickest tippets, and when the fish stop taking our beetles we'll have our answer." Someone else must've said, "Yeah, but what if the fish gets full before it is presented with a tippet too readily apparent... how will we know the difference?"

So they sent down as the first beetle on glued to a ship's hawser, relatively speaking. They 'knew' is would be rejected, and so the fish just couldn't be satiated prematurely, right?

Wrong! What they discovered was that it made no difference at all (appearance wise). If you stop and think about it, putting the finest light grey human hair upon the surface of the commode in good light will reveal it plainly, via the impression it makes in the surface film and the differential refraction makes it appear like a bit crack in the fish's ceiling leading directly to the dry fly. Nevertheless lots of dry flies get eaten. So its not a matter of a leader being invisible to fish, in most cases.

Those PA trout detected what they were looking for (a beetle), and ignored everything else that had no direct bearing on their security. The first beetle down the 'pike' disappeared in a relaxed and satisfied gulp. I gather they repeated the thickest tippet bearing beetle, thinking it must've been a mistake and wouldn't happen twice... but it did. All those carefully glued up much finer tippets on beetles for nothing!

Well, not exactly nothing, but something unexpected perhaps and profound. Bottom line: fish are quite used to seeing all manner of non-edible stuff down there, and its ignored. They aren't so discriminating that they are just waiting to identify what's wrong with our offerings... they are simple creatures only capable of seeking out what might be right about them. There may be some exceptions in certain venues for certain species where a finer line enjoys a big advantage (slab bluegills under the ice in gin-clear Deep Creek Lake come to mind) but I doubt very much that the average fish in the average setting thinks, "You know, I was all set to gobble that thing until I noticed just how thick that strand leading to it appeared to be, and then I got worried that an angler might be at the other end just waiting for my strike, and so I changed my mind." "Had it only been a few microns thinner, I wouldn't have given it another thought, really." In decent clarity of water, fish can probably see just about any line we might possibly use. Even then, it may be that the operative advantage is that the tiny lures and baits used for those 'gills in that cold water simply hang straighter and fish better on the ultra-thin, less given to coil stuff.

Remember, fish don't have a mind to change... just good survival instincts. As I'm fond of saying, they aren't finny little Einsteins bent on making us look bad. They don't have to be, as so often we take care of that ourselves by what we do, or fail to do while fishing.


http://www.tidalfish.com/forums/showthread.php/308095-Braid-without-Leader