A simple technique is presented for reducing the fluorescence of living scorpions by prolonged exposure to UV light. Scorpion's fluorescence peak can be eliminated by a 1-mo exposure to low intensity UV light. Although the fluorescence peak returns within 1 wk after removal from UV light exposure, the magnitude remains reduced. This technique potentially opens up new options for testing a variety of hypotheses about possible functions of scorpion fluorescence including potential effects on cuticle strength, visual responses, predation, cannibalism, and mating.