i found this research. combining this with a screened bottom board to aid in ventilation could provide some protection and prevention. Controlling small hive beetles (Aethina tumida Murray) in honey bee (Apis mellifera) colonies using a modified hive entrance. Ellis, James D., Jr., Keith S. Delaplane, H. Randall Hepburn, & Patti J. Elzen. 2002. American Bee Journal 142(4): 288-290 ABSTRACT This study was designed to test whether colony invasion by adult small hive beetles can be reduced by replacing the regular entrance of a hive with a ¾-inch (2-cm) PVC pipe located 3-4 inches (7.6-10.2 cm) above the bottom board. Colonies with pipe entrances had significantly fewer adult beetles (46.9 beetles / colony) than open colonies (107.7 beetles / colony). Pipe entrances did not directly affect the amount of sealed brood in a colony nor the temperature inside colonies. However, brood significantly affected temperature inside colonies and there was a tendency for reduced brood in colonies with pipes; temperature increased as the amount of brood in a colony increased. Brood did not affect the number of adult beetles present in colonies. This experiment shows that modifying a colony's entrance may help control small hive beetles, but more work is needed to offset unwanted effects of reduced colony entrances. _________________________________________________________________ Protect your PC - get McAfee.com VirusScan Online http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963