When do you change a fly

Interesting question, and some guys may answer it directly as you asked it.  But, let me start with this.  Not catching fish isn’t always a matter of changing flies.  I make it a point to keep track of time.  If after 20 minutes I am not satisfied with the action, I make changes that I think will improve my odds based on the conditions.  Yes, if I have lost confidence in my fly, I will change it.  But more often than not I will change my depth or change where I am fishing first.  Often, I find I am simply not deep enough.  Also, too often we beat the same water to death where the fish have been spooked or simply not active or not present.

Those last two sentences are often my problem. I’ve realized that I’m far to slow in covering ground or there aren’t fish there. This has been key for me when fishing outside of the parks or on some of the Blue ribbon streams.  I’ve really made it a point this year to really look at the area where I’m fishing before I cast.  Those little guys are hard to see sometimes, so I’ll still make half a dozen drifts or so through an area.  If those don’t yield any thing AND I’m not seeing any fish, then  I’ll move on.  I’ve stopped spending a lot of time in an area trying to wish a fish in there.  If I do see fish, then I might spend some more time making sure that I’m hitting depth.  This has seemed to help bump up the numbers of fish I’m catching.