Great idea. I would hope that among flyfishers there is a very high integrity level. My buddy found an extremely large and well-stocked fly box on the Big Lost River in Idaho several years ago. He returned it to our local and favorite fly shop quite a ways away in Idaho Falls, ID. The next day, the angler who lost the box was grousing about it to the fly shop owner who thereupon produced the missing fly box. A lucky combination of a good deed and timing, a name, address, phone # would have been much easier.
I write on the outside of all my boxes with black permanent marker with all of my pertinent info.
Kelly.
Tight Lines,
Kelly.
"There will be days when the fishing is better than one's most optimistic forecast, others when it is far worse. Either is a gain over just staying home."
Roderick Haig-Brown, "Fisherman's Spring"