A Silver March Brown wet fly pattern is designed to be fished below the water's surface to attract trout. They are tied as deceivers or attractors. The silver body helps get the trouts attention.
WET FLY PATTERNS. Hook size 12 14 - $US each
With the addition of a silver body this traditional pattern has been turned into a good baitfish streamer. It is ideal for imitating shoals of fry, sticklebacks and minnows. It has been used as a successful sea trout fly for years in Europe. The bigger hooks make it ideal for large and smallmouth bass as well as Salmon and Steelheads. It is peculiar that this pattern should include the month of March in it's name since the natural insects are not confined to hatching in this month. These flies represent the two different insects that are commonly given the same name: the March Brown (Rithrogena Germanica) and the Late (or False) March Brown (Ecdyonurius Venosus). The March Brown likes large stony rivers. Hatches are often on a grand scale in the middle of a spring day.
The March Brown pattern is one of the oldest angling flies around. Look for hatches of the March Brown in the late spring just after lunch time. The Late March Browns hatch in early summer after the March Brown hatch. Some years may bring a late season hatch if there is hot weather. It is the emerging nymphs of this mayfly that are regularly eaten by trout, but duns and egg laying female spinners that drown in the water are also taken. That is when this wet fly streamer pattern is a killer.
After hatches of tiny midges and Blue winged olives the March Browns are normally the first large mayflies of the year. They always seem to hatch in cold rainy afternoons. The Autumn Dun (Ecdyonurus dispar) is often confused for the March brown insect as the two are of similar size and appearance. It also favors stony or boulder-strewn rivers as well as the shores of stony lakes. The duns emerge during the day from mid to late summer. The ones that do not make it, flounder and drown in the water are the naturals this fly imitates in the smaller sizes.
The hard to find real March Brown
Although many fly fishing anglers have used the famous March Brown dry fly with success I bet very few have encountered the natural insect this fly was designed to imitate. The true March Brown’s Latin name is Rithrogena germanica. The success of this fly design is that it is an acceptable imitation for a number of other May flies. I have been fishing on lakes where colleagues have shown me natural insects they have captured and pronounced them as March Browns in locations where the real march browns do not live. Many anglers confuse the large Dark Olive, that is a common may fly found on many rivers and streams in the spring, with the natural March Brown.
To add more confusion, scientists have identified a species as the false March Brown because of its similarity in appearance. The Brook Dun and Autumn Dun also looks similar to the March Brown but differ in behavior. In Britain I have been fishing during hatches of the real March Brown on the rivers Deveron, Tweed, Annan, Nith, Eden, Usk, Lune and Ribble
Identification of the March Brown is relatively simple. The Dun and Spinner stages are large flies, smaller than the Mayfly, but noticeable larger than many of the upwinged flies of spring like the large dark winged olive. They have two tails unlike most mayflies that have three. The body of the dun is dark brown with broad pale-buff or yellowish bands. The wings of the dun are light, warm brown, with patches and blackish lines. The large dark olive in contrast, has a nearly uniformly grey coloured wing.
The spinner stage is easily identifiable by size and colorization. The body is a deep ruddy-brown and the wing is transparent with black veins. Do not worry too much about having a fly to match the March Brown Spinner fall. I have yet to see this happen in significant numbers on which trout feed fastidiously. The imitation of the March Brown is restricted in reality to the nymph and dun stage.
In Britain the hatches of the true March Brown occur at different time to the other flies of similar appearance. They normally occur in March and April with a few hatches in May. These stragglers mix with the False March Brown hatches. The March Brown nymph is a stone crawler that does not leave the river bed unless dislodged, until it is ready to rise to the surface to hatch. The most effective nymph imitation of the rising insect is a soft hackle wet fly pattern. They also work as drowned dun imitations. The dry fly pattern is ideal for the hatch so long as you match the size of the real insects.
One of my greatest pleasures in life is flyfishing using a long line the team the buzzers, especially when the trout hit the nymphs with a solid thump. I love it if the trout are in the mood for a chase. Riding a soft wave with a team of wet flies is fantastic, especially if it results in a firm hook up. The Silver March Brown is one of my most productive flies. Greg Harrison, Manchester, UK
I fished most of May in Hokkaido, Japan. March Browns were everywhere. You could set your watch by the hatches - 1100-1500. But then they still had 2 m of snow and the locals reckoned nature was at least 6 weeks behind schedule! I used 'Damp' flies - quite large - fished in the surface film and tweaked to imitate the struggling adults. Worked well! The colour didn't seem to matter - just the size and outline. How much colour does a fish see as it looks up at a silhouette!? In the past two years I've spent three months fishing in Hokkaido. They are where Scotland was in the early 18th C. BTW, you realise western style fly fishing arrived in Japan with the GI's after WWII? Up until then they only had the tenkara flies, which I gather are catching on Scotland's moving waters! Gregor Fulton McGregor Hong Kong