A housing has a length adjustable to match the length of the bee entrance of a common type of brood chamber and a width at least equal to the width of that bee entrance. The housing includes screened openings or other ventilation provision to permit air to pass through the bee entrance of the brood chamber. One or more arms or other clamping device on the housing holds the housing securely over the bee entrance to prevent bees from entering or leaving the brood chamber. The device facilitates transport of bees as well as laboratory control of African bees.