How do the fish know?

 Don't know if I've gotten smarter in my senior years or if I've just turned into a wuss.  Arrived at camp at 12:30 and had no urge to go out into the wind and fish.  Got things put away, watered the orchids (with a frost warning I brought them inside tonight),  sat down and fell asleep doing a crossword.  By 3:30, with the wind still capable of blowing my hat off, I headed out.

Went to the BK searching for isos and found some.  If you find where the isos are hatching in profusion you will find the rainbows lined up to eat them.  In thirty years I have found perhaps half dozen of those places.  Unfortunately the isos have never hatched in one of the hot spots for more than a couple years and when they are gone so are the bows.  The place I fished had isos but in modest numbers and the number of fish feeding on them was also modest. For starters they wouldn't eat my isos, they also wouldn't eat my little brown caddis (they are hatching now) or my olives.  Found a fly they would eat (it wasn't a hebe) and hooked half a dozen fish. Broke off a good one when he slammed the fly as it hit the water in a riff no more than six inches deep. The pool wasn't far from one of the former "iso hot spots" so I gave it a try, never saw a fish.  If you see multiple iso husks on the rocks along the shore line it's a good place to try. Conversely, an absence of iso husks means you're probably wasting your time. 

Left the Bk and drove to the BR in time to see two anglers leaving the pool I intended to fish.  There were spinners in the air and on the water and brown caddis hatching so I stayed. It was too late for the isos and never saw a single white fly. Found a few sippers.  Broke off the first one when he unexpectedly slammed my spinner (an equal and opposite reaction is not a fly fisherman's friend).  Got a couple of nice rainbows to quietly sip my replacement spinner which capped off a very nice late afternoon of fishing.