Fox’s Poopah

Most fly boxes already carry plenty of caddis nymphs and a few adult patterns. Dedicated caddis pupae, however, are often missing. They aren’t an all-day fly, but during the short period before a hatch they can turn an average day into a great one, particularly on rivers.

Caddis are one of the few insects that are present throughout much of the trout season. They’re found in almost every water type and in enough numbers to make them a dependable fly choice at almost any time of day.

That quiet spell late in the afternoon, when the nymph fishing has slowed but the evening rise hasn’t yet begun, is often when trout switch their attention to ascending pupae.

Like their terrestrial cousins, the moths and butterflies, caddisflies go through a pupal stage before emerging as winged adults. After leaving their cocoons or cases, the pupae drift briefly before swimming towards the surface to hatch. It is this upward movement that the fish key into.

Pupae are surprisingly active swimmers, so don’t be afraid to impart some movement to your fly. Short lifts during the drift or allowing the fly to swing at the end of the drift all imitate the ascent the fish are expecting. Another effective approach is to fish down and across with a heavily weighted pattern. Takes often come as the fly first begins to rise at the start of the swing.

One of my favourite patterns for this stage is Fox’s Poopah. It was developed during the late 1980s by Tim Fox in Chico, California, after he found a cinnamon-coloured chenille that closely matched the caddis pupae collecting on his waders while fishing the Sacramento River. A few refinements over the years produced the fly we know today. Its short chenille body, prominent legs and bright underbody capture the key features of an emerging caddis pupa without unnecessary complexity.

I prefer a Hanák H260BL for most of my pupae patterns. Its short shank means a size 14 has a body length closer to a conventional size 16, while retaining the gape and strength needed to handle larger trout in fast water.

The pearl tinsel underbody is one of the fly’s defining features, representing the gas bubble that helps the natural pupa rise through the water. Covering it with the translucent chenille creates just enough flash without becoming overly bright.

Before tying in the chenille, singe the end with a lighter. This seals the fibres to improve durability and creates a natural taper to the abdomen. As you rib the body forward, keep the chenille centred along the top of the shank. If it twists around the hook the finished fly can spin in the current.

For the legs I normally use ringneck pheasant rump, although partridge or hen hackle fibres work equally well. Keep them slightly shorter than the body and add two long mallard flank fibres as antennae. A sparse collar of ostrich herl finishes the fly, adding movement without hiding the profile.

Pupae can become active at any time, but activity increases noticeably before a hatch. The hour or two leading into the evening rise can produce some outstanding fishing, and the same principles apply in stillwater. Fish a weighted pattern deep under an indicator or retrieve it slowly along weed-bed edges through the afternoon. As the light fades, switch to an unweighted fly fished higher in the water column.

Another effective presentation is the Leisenring lift. Cast ahead of a feeding fish, allow the fly to sink, then steadily draw on the fly line or lift the rod tip so the fly rises naturally into the trout’s path. It remains one of the most convincing ways to imitate an emerging caddis.

Don’t assume every retrieve has to be slow. Pupae can swim surprisingly quickly and, particularly in stillwater, increasing your retrieve speed can often be the trigger.

My own lightbulb moment came one frustrating evening while fishing a team of pupae to actively feeding trout without any success. More out of desperation than confidence, I replaced the point fly with a large Woolly Bugger and stripped it back as quickly as I could, hoping for a reaction. The first fish I covered ignored the bugger completely but smashed the remaining pupa on the dropper. Since then I’ve never been afraid to move pupae quickly when the situation calls for it.

Tie a few Fox’s Poopahs to match your local caddis and give them a swim before the next evening hatch.