Spotted Caddis

Other Common Names: Net builder, net-spinning caddis, gray caddis
Scientific Name: genus Hydropsyche

This case-less caddis acts like a spider: larvae build little nets in the crevices of rocks and capture drifting plankton for their meals.

Their preferred habitat is riffles and runs. They often drift in the current, so where there are large populations, trout will feed on them year-round. A larva pattern dead-drifted near the bottom can be effective very effective in spring and fall, and even in winter.

Many species are pale green and look a lot like the green rock worm or green caddis ; they are often found in the same kind of water and can be imitated with the same patterns and tactics. In other waters, spotted caddis larvae are more tan or brown.

Pupation occurs in the same water that the larvae lived in. During a hatch, dead-drift a pupa pattern near the bottom in riffly water or just below riffles. An unweighted pupa pattern can also be drifted near the surface, or you can present a Soft Hackle with a wet-fly swing. Another good strategy is a dry fly with a pupa pattern as a dropper or trailer; the dry fly acts as an indicator and sometimes is taken by the trout.

After the hatch, errant and unlucky adults fall onto the water, and a dry fly is the right choice. Bankwater downwind or downstream from overhanging trees is a good place to cast your dry.

Females swim or crawl underwater to lay eggs. You can fish a dry at this time, or go subsurface with a Soft Hackle or Diving Caddis pattern.


How to Match a Spotted caddis

Hatches are matched from Westfly's database of "standard" fly patterns.

Size 12-14 Uncased Caddis. Body: tan, brown, yellow-tan, green
Riffles, runs, just below riffles: indicator, tight line
Size 12-14 Soft Hackle. Body: tan, brown, yellow-tan, green; Shroud: tan
Riffles, runs, just below riffles: surface swing, shallow nymph
Size 12-14 . Body: tan, brown, yellow-tan; Shroud: tan
Riffles, runs, just below riffles: indicator, tight line, shallow nymph
Size 12-14 Deep Sparkle Pupa. Body: brown, green; Wing: brown and gray
Bankwater near foilage: indicator, tight line
Size 12-14 Elk Hair Caddis, Parachute Caddis, X Caddis. Natural gray
Size 12-14 Goddard Caddis. Body: brown; Wing: black
Riffles, current seams, backeddies below riffles: standard dry fly, skating
Size 12-14 Diving Caddis, Soft Hackle. Body: brown; Wing: black
Riffles, current seams, backeddies below riffles: surface swing, shallow nymph, rising nymph


LARVA COLOR: Light green, tan, tan-green, brownish

PUPA SIZE: 10-15 mm

PUPA COLOR: Body--Tan, brown, or yellow-tan. Shroud--tan or light green

ADULT SIZE: 10-15 mm

ADULT COLOR: Wings--Mottled brown and gray. Body--Brown, green, brown-green.

OTHER CHARACTERISTICS: Caseless (free living) larva. Larva has dorsal plates on the three sections of the thorax. Body, wing, and shroud colors can vary, so it's always best to check a natural insect where you are fishing. Body and wing colors will darken when the insect is ready to lay eggs.