Caddisfly Life Cycle & Hatch

RiverBum Staff Jun 25th 2021

Caddisflies haven’t gotten the love historically that mayflies have gotten from anglers. However, that seems to be changing. One night at dinner with my friend Nino he was making fun of me on how many flies we carry at RiverBum. Nino likes to get a good rise out of my wife and I, and this night was no exception. He belts out “all I need are three flies. Adams, Tan Caddis, and Pheasant tails, and I’ll out fish anyone”. Of course, I shot back as to why he’s always panhandling for flies out of my fly boxes. The point is, caddis have a very worthy place as a top insect to carry in your box, and know their behavior.

Where can you find them?

Caddis flies are found in ponds, streams, lakes, and rivers. Cased caddis surrounds themselves with debris to make their own cases so they can hide and grow while having protection as they move.

You can determine water quality by the presence of caddis. Caddis do not like water pollution and cannot thrive in poor quality waters. They are mostly nocturnal; the adults typically hide in vegetation during daylight. Mating occurs at dusk typically in flight. You can often spot them skating across rivers or stillwaters throughout the year.

When do they hatch?

Caddis will hatch at different times of the year depending on the type. For instance, the American grannom or the Mother’s Day caddis in the West would hatch during the spring. Their hatch signifies spring’s arrival and the last good dry fly fishing opportunity prior to the spring runoff from melted mountain snow. The hatch gradually progresses upstream daily. Caddisflies begin hatching off generally around late April and depending on the species into October with the famed October Caddis hatch.

Hatching often occurs in the evening. Trout feed on nymphs quite regularly as well as the adults. The adults zoom the water and is truly a sight to see. However, I have found that mostly smaller fish feed on the dries. My theory is that the larger fish aren’t going to actively go after such fast forage. I’ve caught my biggest fish on nymphs and emergers. But hey, its just a theory. As Nino would say, just give me an elk hair caddis.

The lifecycle

Female caddis flies lay eggs in or on the water. These should hatch in a few weeks. Eggs hatch into larvae, which look like long, cylindrical nymphs. The nymphs create cases, swim, or make nets. Adults emerge with tent-like wings and long antennae. Their lifespan is typically short, as most only exist to breed and do not eat.

Dry flies

Caddis dry flies can help you find active fish. RiverBum carries a great selection of caddis fly fishing flies contrary to the advice of my friend Nino. .

Elk hair caddis flies are buoyant, visible, and will attract fish. It is also an ideal pattern for fish swifter water when it is warm out. Fish will gravitate to swifter moving, more oxygenated water and key on these bugs. The caddis fly is a go to fly when I’m fishing a two fly hopper dropper set up. I run a terrestrial or a rubberleg stimi and with a caddis. It’s a great combination

Nymph

While the dry flies get the most attention, arguably the nymphs catch more and larger fish. Speaking of the aforementioned hopper dropper set up, during July and August its hard to beat a Crystal Rubber Leg Olive Stimulator with a Bjorn’s Baddest Caddis and have Nino taking your grip and grin shots