Marabou comes in several configurations in each package. There is Marabou with short stiff stems and short, fluffy fibers. This kind of marabou works great for Leeches and Wooly Buggers or or any application where the plumage doesn't need to be wrapped around a hook. About 1/4 of the feathers have long fibers and fine stems. This kind of marabou works best for medium size Alaskabous, Marabou Spey Intruders and Marabou Tube Spey Intruders. Fine stemmed marabou can be wound on the tube or hook like a hackle.
Human eyes don't see into the UV2 light spectrum, but many other animals and insects do. Some scientists believe that fish do. Steelhead and Pacific salmon anglers have been using fluorescent lures and flies for years. We know flies made from fluorescent red, orange, yellow and green are deadly when used for anadromous fish. Bill Black from the Spirit River Company started experimenting with UV2 dyes on all colors of fly tying materials may years ago. These materials created a loyal fan club.