Anglers Fishing Guide to Montana Insects: Stoneflies

An Introduction to Stoneflies

Stoneflies provide a feast for trout. Their often-stout bodies are irresistible. But tiny “stones” (as many anglers refer to them) also grace Montana rivers near Bozeman, representing a good quantity of Montana trout diets.

Characteristics of Stoneflies

• Stoneflies are reluctant to fly and if they do, they do so quite clumsily.
• Transparent wings lie flat on over their backs, and the two distinct wing pairs are obviously seen when flying.
• Two tails grace their long bodies, and they are quite short, typically.
• Most are formidable carnivores, but some are herbivorous.
• Nymph size correspond to their adult size, so large and small nymphs crawl along rocks
• They range in color from yellow, tan, black, brown, or mottled. Stoneflies range in size corresponding to hook sizes #4-#16.

Overview of the Stonefly Lifecycle

• Stoneflies undergo an incomplete metamorphosis which includes egg, nymph, and adult stages.
• Lifespans of 1-3 years begin with their eggs laid on or in freshwater when the female dips her abdomen below the surface.
• Nymphs molt several times durign their lifespan as they slowly outgrow their exoskeleton.
• The final molting and mating occurs on land.

Montana Fly Fishing Stonefly Hatches of Note

• The Montana fly fishing season kicks off with the skwala hatch on the rivers near Missoula in early spring.
• Salmonflies start to show up in late May on the Big Hole River, followed closely by golden stones and yellow sallies.
• Fishing the salmonfly hatch on the Madison River is a perrenial favorite Montana fly fishing guide trip experience.

Top 10 Stonefly Dry Fly Patterns for Fly Fishing in Montana

Montana Fly Fishing Stonefly Hatch Blogs