Silver Spey
Pattern information
With its shiny, translucent body and low-set, mottled wing, this Spey fly is a dead ringer for a salmonid fry of various kinds.
In Summer, you will find Atlantic Salmon (and Steelhead) busting juvenile baitfish for various reasons. This fly works very well under these conditions.
I do not recall ever catching a fish on this fly under any conditions other than sunny skies. It is so brilliant that you stand a chance of frightening fish if you fish it in the shade or on cloudy/overcast days.
I suppose that a Jungle Cock eye would complete the baitfish look, but it works just fine without them, so I'll save them for the display flies.