The Ephemera Danica is the largest mayfly in Norway. Measuring up to 2,5 centimeters (one inch) the hatch of this beautiful mayfly is the most important during the season. When these guys appear, the big and picky trout looks to the surface for food.
The E.Danica thrives in sandy and rocky riverbeds. They live as nymphs for two (some three) years, buried in the sand. Only shortly before hatching they crawl out of the sand, making themselves available for trout, grayling and other fish.
It’s absolutely possible to fish the Danica as a nymph, but my experience is that it’s not worth the while. The Danica nymph is most effective a short period and early in the hatch cycle. As soon as they start emerging in numbers, fish look to the surface and start feeding on emergers and duns.
In my “home” river, the hatching usually starts 20. June – give or take a few days. The peak of the hatch cycle is usually after 10 days, but it is possible to fish a Danica hatch for at least three weeks after the first mayflies start emerging.
The first week of Danica fishing is the time when you use an emerger imitation. The efficiency of a well tied emerger is enormous. Actually, I believe that an emerger will outfish both a nymph and a dun in the first period after they have entered the last phase of their lives (as an emerger, dun ands spinner).
This year the Danica started emerging late in week 24. In the diagram I have indicated the period when the emerger outfished any other Danica imitations. Although I haven’t recorded the data as thoroughly as this year, experience tells me that this year is quite like every other year of flyfishing the Danica.
In the digram below you see some of the notes I have taken during this year’s Danica hatch. I will get back to different strategies for successfully fishing the Danica hatch, based on the data I have registered and notes from my flyfishing diaries.