NymphNet Builder Caddis
The Net Builder Caddis is a realistic caddis larva imitation that replicates the free-living, net-spinning caddis species that build silken nets to filter food from the current. This weighted pattern features a Thinskin casing over Sow Scud Dubbing for a translucent, segmented body, a white Z-Lon tail suggesting the anal gills of natural larvae, and ostrich herl legs that create movement and suggest the thoracic legs of natural caddis larvae.
Spring, Summer, Fall
Intermediate
Trout
Overview
This Charlie Craven pattern from Charlie's Fly Box represents the often-overlooked net-building caddis larvae that are incredibly abundant in freestone streams. Unlike case-building caddis, net-spinners live in silken retreats attached to rocks where they filter organic matter from the current. The pattern's construction creates a realistic larval profile with the Thinskin casing providing the characteristic translucent appearance of natural caddis larvae. The white Z-Lon tail imitates the distinctive anal gills, while the tippet ribbing creates segmentation and adds durability to the pattern. The lead wire underbody ensures the fly reaches the bottom quickly where natural net-building caddis live.
Pattern Characteristics
Materials
Hook: Hanak 300, #10-16
Thread: UNI 8/0, black
Weight: Lead Wire, .020
Tail: Z-Lon, white
Rib: Tippet Material, 3X
Casing: Thinskin (Fly Specks), olive
Body: Sow Scud Dubbing, olive
Legs: Ostrich Herl, gray or black
Fishing Tips
Season
Most effective from spring through fall when caddis larvae are actively feeding and growing. Particularly productive during periods of high water when dislodged larvae are available to trout.
Presentation
Fish on a dead drift near the bottom, mimicking a dislodged larva tumbling in the current. The weighted design helps the fly reach the feeding zone quickly in faster water.
When to Use
Select this pattern when fishing freestone streams with good caddis populations. Look for rocks with silken nets visible on their surfaces as an indicator of abundant net-building caddis. Effective as a prospecting pattern or when trout are actively feeding on subsurface food.
Water Type
Designed for moving water, particularly riffles, runs, and pocket water where net-building caddis are most abundant. The weighted construction handles faster currents effectively.
Rigging Suggestions
Fish on a standard nymphing rig or euro nymphing setup with a tight line. Works well as a point fly in a two-nymph rig or as a dropper behind a larger attractor pattern. Use 5X-6X fluorocarbon tippet.
Visibility & Floatation
This is a subsurface pattern designed to sink quickly and drift near the bottom. The olive coloration blends with natural stream substrates while the ostrich herl legs provide subtle movement that attracts attention.
