CADDISFLIES have long taken a backseat to mayflies as must have imitations. These days, due in large part to the work of Gary LaFontaine, caddis imitations receive their fare share of time on the end of the tippet, but many anglers still assume all caddisflies are pretty much the same.
In many species, the pupae become very active just before emergence and drift along the bottom of the river, sometimes for hours. The "deep sparkle pupa" patterns introduced by Gary LaFontaine in Caddisflies are the most popular of many imitations inspired by this behavior. It is a deep nymph fisherman's dream. Sometimes they drift similarly just below the surface for a long time before trying to break through.
Pupae of different species use three different methods to emerge:
• Most species rise to the surface and struggle through. They usually take flight quickly once they're out of the water, but slow species first struggle and drift long distances half-submerged as they wriggle free from their pupal shucks.
• The pupae of some species crawl out of the water on rocks, sticks, and such, so that the adults emerge high and dry.
• Some pupae rise to the surface and swim quickly across it to shore where they crawl out to emerge.
Most caddis pupae are good swimmers, and they use their legs as paddles rather than wiggling their bodies to move.
After emerging, caddis fly adults live for a long time compared to mayflies, in part because they are able to drink to avoid dehydration (mayfly adults cannot eat or drink). This flight period lasts anywhere from a few days to a few months, depending on the species, so mating adults may be seen on or over the water long after emergence is complete.
Many caddis fly females dive underwater to lay their eggs on the stream bottom. Some crawl down objects to do this but most swim right down through the water column. The latter are responsible for my fastest trout fishing action ever -- days when trout raced each other to attack my flies the moment they hit the water, cast after cast.
Others lay their eggs on the surface in various ways. They may fly low over the water, periodically dipping their abdomens to lay eggs. Others land on the surface repeatedly, fussing and fluttering in enticing commotion. Less active species may fall spent to the surface with all four wings spread out. Others ride the water serenely while laying their eggs, and they are the easiest to match with the dead-drift techniques of mayfly fishermen.
Some egg-laying methods keep the adult females safe from trout altogether. They may drop their eggs into the water from overhanging plants, or lay their eggs on the vegetation itself. That way the eggs don't enter the river until the next rain--an excellent drought survival strategy.
Stay Tuned...For the rest of the story, more photos and a few tips on fishing caddisflies...