An Introduction to True Flies
When telling someone you fish with flies, most will immediately picture Diptera, or true flies. These are your typical houseflies, midges, craneflies, and mosquitos (among others). They are prevelant throughout Big Sky country and are an important food source for the wild trout in Montana's rivers.
Characteristics of Diptera
- Diptera are medium-sized insects that feature prominent, compound eyes on a mobile head
- They have one pair of wings that are obvious and another pair that help them fly with ease.
- These flies show great agility when flying due to their wing shapes and thorax adaptations.
Overview of the Diptera Lifecycle
- Diptera displays a complete metamorphosis (egg, larva, pupa, adult).
- Their eggs are laid underwater and last a few days to a few weeks (though some species stay in this stage much longer).
- Their larva are legless and live in freshwater, semi-aquatic or even on moist land. There are several larval (or instar) stages with most aquatic species like blackflies and mosquitos having 3 or 4 of these stages.
- The pupal stage also happens mainly underwater for 10-12 days in warm weather and 25-30 days in cool weather. Diptera pupal cases are made from a hardening of the larval skin.
- Some species are herbivores, but most feed on dead organic matter or parasitize other animals, especially vertebrates, mollusks, and other arthropods.
- Adult flies live in a wide variety of habitats. They primarily survive on liquid food (think plant and animal juices) and eat using a proboscis. Some species feature a cutting or piercing proboscis to penetrate flesh of humans and other animals.
Diptera Hatches of Note in Montana Fly Fishing
- Midges hatch year round and are particularly important to trout as a food source during the coldest periods of Montana weather.
- Winter midge hatches make for some remarkable dry fly fishing in Montana on the upper and lower Madison River.
- Cranefly hatches seldom are prolific enough to attract the attention of rising trout, however, the Beaverhead River is renowned for its hatch during the late summer.
Top 10 Diptera Fly Patterns for Fly Fishing in Montana
Diptera and Montana Fly Fishing
Category: Lower Madison River Fishing Information
Winter Fishing the Lower Madison
Post Date: 01/03/2024
The Lower Madison River is a great destination for fly fishing in Montana during the winter. Snow doesn't accumulate much along the riverbanks and the river rarely freezes. Located just...
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