Scud This post was last updated on November 25th, 2014 at 04:58 pmScud or Freshwater Shrimp Fly Patterns The Scud! These are fresh water shrimp that are a delicacy for trout, they are a favorite food for them. Don’t be crazy and have a nymph box without some of these in it. I have found the scud to be one of the first flies I switch to when it seems like the trout just aren’t eating anything. A lot of times they will eat this when all else fails. This beautiful scud pattern has copper ribbing, and an overall yellow colored synthetic body. This is a good one to really get the fishes attention quickly. A simple but effective trout pattern. A very simple scud pattern to tie, yet very effective. This particular fly is tied with a Transparent back material, brown rabbit fur dubbing, biots on the head and a brown hackle tail.