Mother’s Day Caddis
There’s no getting around the fact that going fishing on Mother’s Day can create some friction!
If you are a serious fly fisher, Nature and modern culture have dealt you a most difficult situation - go fishing during one of the best caddis hatches of the year, or be with your mother or family on Mother’s Day? Should be easy to decide - right? Well if it is either your mother or wife also like to fish and think spending a day casting to thrashing trout is a great way to spend Mother’s Day, or you are a fishing bum living alone in your van.
The big mistake was calling this caddis hatch, “The Mother’s Day” caddis. Come on! With a name like that how can you possibly claim you got excited about the fishing and just forgot it was Mother’s Day? This just isn’t fair play.
Fortunately, contrary to Hallmark and other retailers, Mother’s Day lasts just one day, while the Mother’s Day caddis hatch usually lasts two to three weeks. So, once you get through with your Mother’s Day festivities there should still be time to find some trout feeding on this little caddis.
To start let’s get the name for this caddis straightened out. Technically the Mother’s Day caddis belongs to the family Brachycentridae and the genus Brachycentrus. Thirteen species of Brachycentrus are known in North America, with hatches of different species occurring from April through August. The one species that causes such family challenges on Mother’s Day is Brachycentrus occidentalis, or B.o. for short (hey, why not?). This is almost a completely western species, with great hatches found throughout the Rocky Mountain states all the way to the Pacific Coast. Some also live in the Midwest, but their populations tend to be spotty and rarely produce important hatches. Another species, Brachycentrus americanus, is more widespread, with good populations from the east coast to the west coast. It also produces some excellent hatches, but they are less concentrated and occur early to mid summer, well after any conflicts with Mother’s Day. Both of these hatches are sometimes referred to as the American Grannom.
Like many species that prefer Western streams, B.o. larvae find fast to moderately fast water with a cobble to boulder bottom to their liking. This is a bit unusual for case-making caddis, especially case makers that use lightweight plant material for their cases. B.o. construct neatly tapered four-sided cases, sometimes referred to as chimney shaped, out of narrow pieces of plant material cut and laid transversely. Their total length when mature is about a half-inch long. The shape and size of their cases make them rather easy to distinguish from other caddisflies when you pick up a rock from a riffle.
To feed B.o. larvae attach their cases to the top and sides of cobble stones with sticky silk thread. Once attached they lift their relatively long hind and middle legs up into the water and strain drifting food from the current. The key to safety is staying attached to the rocks, which isn’t always possible. Sometimes larvae purposefully move downstream by rappelling from one rock to another on a length of silk thread. Gary LaFontaine describes imitating such behavior by using a white colored tippet, an interesting idea that I haven’t personally tested. One thing I do know is that the larvae drift periodically in good numbers while still in their cases and trout have no problem eating them case and all at such times. This means fishing a case-like nymph pattern is well worth your time.
Pupation occurs inside the larval case while it is still attached to bottom rocks. Until the pupa completely mature there isn’t any larval drift or available pupae to eat. But once pupation is completed the pupae cut out of their cases and begin the ascent to the surface. This is what angler’s are willing to miss Mother’s Day for. The numbers of B.o. in many Western streams can be huge, so when they start emerging trout gorge on the rising pupa. Plus, these hatches typically occur mid-day from say around noon to three. So if you live close to a good trout stream you might be able to wish your Mom happy Mother’s Day in the morning and catch the fish action in the afternoon.
B.o. pupae run a size 16 (occasionally an 18) with bright green bodies and dark almost black wingpads when mature. Like other caddis pupae they swim well, so a Leisenring lift or wet fly swing that imparts a rising or swimming action to your fly generally works best. You’ll will be fishing in riffles or the runs below them, and often getting strikes with your fly hanging downstream in the current, which can result in missed strikes or broken tippets. To avoid this don’t strike when you feel a fish hit your fly. Instead point your rod at your fly and gently pull your rod tip to the side towards the bank. Their are many excellent pupa patterns for this hatch. LaFontaine’s sparkle pupa, soft hackles, and flymphs are just a few I have had good success with.
Adult B.o. are also a size 16, but much darker than the pupa. Their bodies are mostly black with just a small green band on each side of the abdomen, and their wings are dark-gray to black. While most fish concentrate on rising pupae during the hatch you can also get into some good surface action with adult patterns. Fish dry flies dead drift or with a slight skating action.
After mating on shoreline vegetation females often return en masse to lay their eggs with heavy activity occurring most often in the late afternoon. While many caddis females dive underwater and swim to the bottom to lay their eggs, B.o. females most often lay their eggs on the water’s surface. A spent caddis pattern can be deadly during this activity. Because most females on the surface are dead, a dead-drift presentation will usually be most effective.
Now is the time to go forth and find out if B.o. is emerging on a stream near you. It’s a great hatch, one you shouldn’t miss, and one that hopefully won’t destroy family relations on Mother’s Day. Maybe calling it the May Day caddis would help? Ya, probably not. Happy casts!