Summer Stillwater

By Brian Chan


Contrary to popular belief there is a lot of great lake fishing to be had after the spring to early summer chironomid or midge fishing subsides. Damselfly and caddis fly emergences, although much shorter in duration, offer some great nymphal, pupal and adult fly fishing opportunities. Seasoned stillwater anglers look forward to the annual dry fly fishing that the adult caddis hatch offers and in some waters similar adult damselfly action. However, the most productive tactics for these two insects is often imitating the pupal and nymphal migrations as both insects make their way to complete the transformation to the adult stage.

Both emergences offer the angler visual clues as to when they are occurring as these insects live in water less than 25 feet in depth and often in less than 15 feet. Mature damselfly nymphs swim out of the protection of benthic vegetation that blankets the shoal or littoral zone of the lake and migrate to stands of emergent vegetation such as longstem bulrush or cattail. Here the nymphs crawl out of the water and up the plant stems to complete the emergence to the adult. The migrating nymphs swim up off the lake bottom to within a few feet of the surface of the lake and then swim horizontally through the water. It is easy to see the nymphs in the water as there are often many of them moving on mass to emerge. An even better clue is when pulling your anchor ropes to move and several nymphs fall off into your boat. Damselfly nymphs are relatively slow swimmers and thus make easy meals for foraging trout and char.

Caddis larvae crawl along the bottom substrate and vegetation growing within the shoal zone of the lake. Caddis flies complete the transformation to the pupal stage inside their larval cases which are typically constructed from bits of vegetation, particles of sand or bits of woody debris. Once mature, the pupa breaks out of the larval case and quickly swims to the surface of the lake. Upon reaching the surface a split forms on the back of the pupa and the adult caddis emerges. The newly emerged adult dries its wings by briefly holding them upright like a mayfly to dry them and then quickly folds them tent-like over their back. The adults typically run across the surface film for a short distance before taking flight and landing in nearby riparian vegetation. Trout and char actively pursue the swimming pupae as they move through the water column. The pupae typically swim on about a 25 degree angle to the lake surface. Their hind pair of legs are elongated and feathered which act as oars sweeping them through the water. Anglers will see the pupa swimming quickly through the water column.