The next species of flies are the caddis flies. These are also sometimes referred to as sedge flies. Caddis flies look a little like moths when they become adults.
Larvae and PupaeHatching from an egg, a caddis becomes a worm-like larva. These larvae will find anything they can to surround themselves with for protection. Some surround themselves with sticks or bits of vegetation or even sand bound together with silk that they excrete from their mouths. You would fish this stage about the same as a nymph in that you dead drift the fly down at the depth at which the trout are feeding.
The pupa stage begins anywhere from six months to a year after it is born. During this stage an adult body forms inside the pupa. When it is ready, the adult then emerges out of its covering with quite a show, beginning the final stage of adulthood.
AdultsThe emerging adult produces a gas bubble that floats it to the surface. As it ascends to the surface, the shell expands and bursts, and the adult pops out of the water. Some ascend with such speed that fish leap out of the water after them while others have to rest for a moment before taking flight. They'll test their wings which will attract any nearby trout to strike.
You'll want to simulate your caddis flies to appear as though they are rising to the surface, about to take flight. Cast your fly upstream, allow it to dead drift to the fish, and just before it arrives, lift your rod and fly line to raise the fly.
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