By the time the March Browns arrive, anglers have already been fishing hatches of small- to medium-size mayflies such as Hendricksons and Blue-winged Olives for up to two months. But the first March Browns of the year are huge in comparison. March Browns in fertile waters can easily fill #8, 2X-long hooks and the small ones are #10.
Early March Browns begin hatching in mid-May when the water is often still cold, and they appear during the warmest part of the day, usually from late morning through the afternoon. These mayflies continue hatching through mid-June on the Upper Delaware and often overlap with big Sulphurs (Ephemerella invaria), and the beginning of the Green Drakes (E. guttulata).
March Brown nymphs are in the family of clingers. They are usually found holding on to the bottoms of rocks in riffles and swift-moving glides. Dead-drifting #8-10 nymphs in the riffles is productive, but slowly stripping the flies toward shore, like a streamer, can be better, particularly if the water is high.
The early March Brown duns are strikingly beautiful. The color of their thoraxes and abdomens ranges from creamy tan to pale yellow, significantly lighter than the bold, dark brown markings on their backs and legs. The fly's belly is most obvious to a rising trout, so it's important to properly imitate the belly color.
Imitating the spinners is not difficult. Just about any big (#8-10, 2X-long) Rusty Spinner in your fly box will probably work. The problem is actually being streamside when the bugs hit the water.
Tie up 6 March Brown nymphs, emergers, duns, or spinners and bring them to the June chapter meeting. There will be two raffles.