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Why are caddisflies used as models for artificial fishing flies?

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Caddisfly — caddisfly Adult caddisfly (*Trichoptera*).

Caddisflies are frequently used as models for artificial fishing flies because they serve as a primary food source for many fish, especially trout.12

These insects are vital components of aquatic food webs, and fish actively prey upon them during their immature aquatic stages as well as when the adults are flying. Because trout specifically target the flying adults, anglers replicate the appearance of these insects to effectively attract fish.12