Ostrich Herl can be used several different ways. It is a very good substitute for marabou and can be used as a tailing material.
It is slightly stiffer than marabou and that can be an advantage if you are tying flies to be used in heavy water – where a marabou tail can collapse.
It can be an excellent substitute for peacock herl on midge and nymph patterns. The added benefit is the range of colors available which cannot be duplicated with peacock herl.