March Brown

The March Brown

With the Trout season starting on various rivers throughout the UK in March, fly anglers thoughts switch from Grayling to Trout. The first insect which pops up on the fly anglers radar in March is the aptly named March Brown.

The March Brown (Rhithrogena germanica) is a member of the Heptageniidae family - The Heptageniidae are a family of mayflies with over 500 described species. These flies are generally rather small with two long tails. The wings are usually clear with dark prominent veins. We will learn more about the Heptageniidae family through the season, as they make up the majority of flies the angler is predominantly interested in.

Where To Find Them

March Browns are more commonly found on the larger rocky rivers in the north of England; and throughout Scotland, Wales and Ireland.
March Browns seem to prefer rocky or stony river beds with faster flowing water.

When To Find Them

The March Brown hatch usually starts in the first two weeks of March and will continue until mid-April.
During March and April hatches usually occur around midday and can last for up to three hours, with major bursts of activity only lasting around 15 minutes (have your flies ready before you enter the water!). 

What To Look For

March Browns are generally pretty easy to spot (especially in early March - as they are generally the only up winged fly you will encounter on the river). Later, in April, it is often confused for the Large Brook Dun (which is very similar). The key distinguishing feature of the March Brown is a dark mark in the centre of their pale femur. Remember these flies only have 2 tails.


The March Brown starts as a nymph clinging to stones on the river bed. These stone-clinging nymphs are generally around 1.5cm long (about a size 12 or 14 hook). The nymph then rises through the water column and emerges on the surface. This is the point that trout usually take them (either just below the surface or as they emerge), don't be too quick to retrieve your fly if it starts to sink!
Unusually for one of the mayfly family, trout don't seem to be interested in March Brown spinners (the dying ones on the surface at the end of the day). From a fly fishing perspective the three stages which we must try to imitate are:
  • Nymph
  • Emerger
  • Dun (see above)


The most popular imitations for adult March Browns are either of the dry flies below, don't worry if you don't have these exact patterns, as anything which is in the general colour, profile and size will do. These flies should be fished as you would any other dry fly, the March Brown Upright being especially buoyant. These dry flies should be used as soon as you start to see the hatch appear (remember early hatches of March Brown's don't last long), this can be anytime from 12:00 until 15:00, depending upon weather conditions.

Dry Flies


March Brown Upright


March Brown Jingler




If you are fishing in a morning or cannot see any signs of a March Brown hatch, then nymphs are the way to go, in early season it is sometimes more productive to use a brighter nymph, then the drab more imitative ones.
Always keep in mind how deep and how fast the water is when nymphing in early season, that will tell you how heavy a nymph you need to use. All you need to remember when fishing nymphs in the early season is that you need to be near (or on) the bottom, if you're not getting snagged up every so often, you're not fishing deep enough.


This email is brought to you with the sole intent to spread the information around so we can all maybe learn something. If you would like to buy any March Brown imitation flies for your early season forrays, we do hope that you will consider us and see what flies we have to offer. If you are considering any of the above flies, they can be found using these links:

March Brown Upright
March Brown Jingler

The next issue of Hatch Chat will cover the Stonefly.