Description
The Mayfly Dun: The Moment of Truth (The Crucial Stage)
The stage of the newly hatched adult Mayfly is called the Dun. This is arguably the most critical phase for the fly angler. Depending on surrounding circumstances such as temperature, wind, and weather, the time it takes before the Dun is able to fly away from the surface will vary.
These newly hatched Mayflies are often an easy and vulnerable target for the fish, and many will end up in Mr. Brown Trout’s stomach. When the hatching is frequent, many fish species might become selective and only feed on Duns.
Our Commitment: Perfect Imitation
Our commitment is to provide imitations of the real insect where the fly has the right shape, size, proportions, and colours, and, not least, leaves the correct print on the surface of the water.
This imitation of an adult mayfly in the Dun stage possesses all the right proportions and properties. It looks natural, feels natural, and fish will eat it.
Our Large-Winged Dun Imitation Features:
- Correct Surface Print: The imitation creates the precise silhouette on the water film that triggers the selective fish.
- Optimal Vulnerability: Designed to mimic the wing-drying, vulnerable Mayfly just before take-off.
- High Quality: Exact proportions and colours perfectly match the natural insect.
Recommendations for Best Results
We do recommend you to use a J:son Swivel for all your fly fishing. However, it is necessary to use a J:son Swivel whenever you are fishing a J:son fly in size 1 or 2 to ensure perfect presentation and minimize line twist.
The Spring Giant – J:son Mayfly Dun 2 Mahogany (Hook #12) The Mahogany Dun in size #12 is the perfect imitation of the Large Mahogany Mayfly (Leptophlebia marginata). As one of the earliest and most substantial mayflies to hatch in Northern waters, the marginata is a highly anticipated event for both fly fishers and hungry trout. This dark-bodied beauty often starts hatching in April and May, even when there’s still snow on the banks, providing the first major surface feast of the year.
Tied on a size #12 hook, this realistic imitation features a robust dark brown foam body and J:son’s signature wings that capture the exact profile of the natural insect. Its superior buoyancy makes it ideal for the choppy waters and windy conditions often found during early spring. Whether you are fishing forest lakes or slow-flowing rivers, the Mahogany #12 is your primary tool for matching the first big "dark duns" of the season, offering a silhouette and footprint that selective fish simply cannot resist.