Tom Nakashima wrote:
In California, the visibility of the water on the rivers isn't as great as
in Alaska. On the Arolik River, I could see the rainbows in holding water
up to about sixty feet, the water is crystal clear. Therefore I was able to
see the behavior of these rainbows when I presented the dry fly.

One of the things I learned is good presentation comes into play. I know we
had discussions about light weight tackle, but none of that is going to
happen unless you hook the fish first.

I got to witness the rainbows in the holding water against the opposite side
of the river along the bank. In order to catch fish there, two things came
into play, one is the delicate presentation of the fly, and the other is
time, how long you can keep the fly in place before the current sweeps the
line out and disturbs your presentation. I could easily see the fish in the
holding water, and if I made a hard plonk of the fly, the fish there would
spook and take off. Now I have a less chance of casting back there because
I have already spooked the fish.
I found that if I could make a soft delicate presentation in the holding
water, the fish wouldn't spook.

The other thing I noticed is time, how long the fly stays in the holding
water before the rainbows strike. There isn't much time if you have no slack
in the line before the current sweeps your fly out of position. I was
counting 3-seconds, one-thousand one, one-thousand-two, one-thousand-three
before the current swept my fly out of position, not nearly enough time for
the fish to react in my case. To solve this problem I used the reachcast.
The reachcast incorporates the a mend in the line as you make the cast. In
somecases I like it better than putting in the mend after the cast because
you don't have to pick up the line again, and risk disturbing the fly. The
reachcast had bought me about 4 more seconds for my fly to be in place, a
total of 7-seconds altogether, which was enough time for the rainbows to
react before the current swept the line out of position. I had some great
hook-ups along the river using the reachcast.

The other place that I got to witness, was the rainbows holding in the
gentle part of the river right after the riffles (choppy water). In this
case the fish were faced upstream with their mouths open catching food the
riffles churned up. Casting upstream about 45 degrees into the riffles were
a lot easier, and watching the fly drift into the smooth section of the
river made for some easy strikes.

In both of these areas I just described, the fishing was consistently
productive for me. Other areas was casting into the current, putting a mend
in and letting the fly drift and hoping for the best. Although this wasn't
as productive, it was a change of pace.

I have read about these behavior in rainbows, but this is the first time I
got to witness it.
fwiw,
-tom fish a glacial river like the Kenai and you cant see 2 feet