the trout's window

[afishinado]

interesting video >


How Does a Trout Catch a Fly?: Marinaro's "Edge of the Window Theory" from Paul Kenyon on Vimeo.

 

[sgrim]

And an excellent read that still fascinates me.

 

[gulfgreyhound]

I better brush up on my math skills. Spot and stalk in a few weeks.GG

 

[Nymph-wristed]

Great book I read as a young bull of 9 or 10 years old!

 

[Mike]

The visual cone also makes individuals moving along or standing on a stream bank edge, especially a high bank, as in farm country, to appear as if they are stretched out over the stream when the angle at which the edge of the cone exits the water intercepts the individuals' forms. The implication for fishermen and angling success is obvious. To my recollection, I never read the scientific paper that describes the cone, but it was discussed in a graduate level fish behavior course at PSU in 1974, so the concept has been around for quite a while.

 

[foxtrapper1972]

Marinaro's stuff is mostly too complicated and "heady" for me. (prefer Fox). (And those testing ground streams have really changed since his day!) I was always having a hard time understanding this visual cone concept after reading that book. the video does a good job of explaining it.

Now I understand the early warning the trout gets and how a trout inches from the surface swims 10 ft or more to take a floating insect and how they see more than just a window above them with clarity.


Is this idea of the visual cone proven or is it just a theory?

I suspect in coming years we'll be learning more about how different creatures "see" the world.

 

[afishinado]

foxtrapper1972 wrote:
Marinaro's stuff is mostly too complicated and "heady" for me. (prefer Fox). (And those testing ground streams have really changed since his day!) I was always having a hard time understanding this visual cone concept after reading that book. the video does a good job of explaining it.

Now I understand the early warning the trout gets and how a trout inches from the surface swims 10 ft or more to take a floating insect and how they see more than just a window above them with clarity.


Is this idea of the visual cone proven or is it just a theory?

I suspect in coming years we'll be learning more about how different creatures "see" the world.

It's a scientific law....Snell's Law.


Interesting stuff (for FFing geeks like us, anyway).

Think of it in reverse. If you're wading and see an object in the water it's actual position is not where it appears when looking down in the water because light is refracted (bent) and the object is actually closer than it appears.

(That why you must aim low, Foxy when you go out bow fishing for gemmies... )

 

[Mike]

Fox-t,
Good point. The acoustico lateralis system also plays a major role in fish behavior, including feeding. The most extreme example is in cave fish. I don't know that an insect without movement is perceived, but if there is some threshold level of movement occurring, then pressure waves are being sent out that can be received by the lateral line system, which, by the way, includes receptors on the head. We fly and lure angler's talk a lot about sight, but often forget about the fish's other sensory systems.

This is not to say that sight is not important. Scientific study has revealed that Largemouth bass in turbid water are often in poorer condition, meaning less plump, than those in clearer water. Likewise, young bullheads, a LMB staple, are less vulnerable in turbid conditions.

As a student, I watched joe Humphreys nymph trout from Spring Creek almost at will under muddy conditions. I marveled at that at the time. He cast up along the shoreline, which probably helped visibility, but it may have also been a demonstration of the interaction between vision and the lateral line system.

 

[Mike]

Very good Afish, it's starting to come back to me now. Thus, the proof of the angler on the embankment example.

 

[Sylvaneous]

foxtrapper1972 wrote:


Is this idea of the visual cone proven or is it just a theory?

Physically, yes, this is what happens with light entering the water. If you mean the trout using the edge of the cone to kind of 'track' the prey as 1) the prey drifts downstream and 2) the trout moves shallower
this could be checked.

If the water is clear and smooth, like in a pool, you can see how fish hold in about the same depth, OR if you know the depth of the rock one is sitting behind. Then you would know where the upstream edge of the window is. As the fish comes up, it's upstream window extent would come closer to it. IF this happens right along with the speed of the current, and therefore, the food item stuck in the current, then you could have one piece of proof that this is what trout do.

But I would say this a quite idealized situation. In about all bouncy, rippled water situations, the trout come up and smack the fly. Those fish weren't carefully tracking, just whacking. The window would be too broken and the current too swift .

 

[sgrim]

foxtrapper1972 wrote:
Marinaro's stuff is mostly too complicated and "heady" for me. (prefer Fox). (And those testing ground streams have really changed since his day!)

You strike me as a Brautigan fan ....
I enjoy my copies of the Dry Fly Code and Ring of the Rise for the pictures of the Letort and Big Spring in days of yore.

 

[foxtrapper1972]

sgrim-You got me. Wondered if anyone noticed...Yes. Brautigan and Marinaro are worlds apart but I do appreciate them both!

 

[troutpoop]

I really enjoyed this video and thoughts. Its a bit deep but provided useful information. I store this type of information to use and become a better angler.

 

[troutbert]

What useful, practical tips come from this?

 

[troutpoop]

I would say remembering to stay low on approach and understanding the window of view a trout has through the surface.
Every little tidbit of info I can glean helps me be a better angler.
Just my point of view, not trying to stir the pot.

 

[Fly-Swatter]

+1

Also. lower casting angles help, when practical.

 

[jacob]

The Brautigan reference has got me cracking up over here...

This is definitely interesting and I think reinforces all of the things we've heard for a long time, but in (some sort of) a visual way - though I am not sure about every minute detail in this- especially the idea of a fixed angle of vision, it does provide a level of guidance that is helpful. (just stay low and move slow)