The Wardecker watering device was beneficial to colonies of honey bees,Apis melliferaL., stressed by confinement, heat, and lack of water in the desert southwest. The benefits included larger populations of adult bees, more sealed brood, less mortality of unsealed brood, and no mortality of queens or colonies. Colonies in the northern Rocky Mountain area where such stress did not occur did not benefit from the waterer, and those without it generally had more bees, brood, and honey.