Submitted to: Bee Culture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 15, 2008
Publication Date: February 1, 2009
Citation: Cargel, R.A., Rinderer, T.E. 2009. Effects of Varroa destructor Infestation on Honey Bee Queen Introduction. Science of Bee Culture 1(1):8-13; supplement to Bee Culture 137(2). 2009 Interpretive Summary: In recent years, beekeepers have noticed increases in rates of queen loss in colonies when attempting to introduce new queens to colonies. The colonies usually rear their own replacement queens but costly queens of a desired stock are lost and the colonies develop more slowly and are less productive. This study examines one possible cause of the increase in queen loss, the infestation of colonies with varroa mites. Higher rates of varroa infestation resulted in higher rates of queen loss. Colonies that lost queens and replaced them with a queens they produced themselves were smaller and, at the end of the queen replacement process, where more highly infested with varroa. Beekeepers can reduce queen loss by controlling varroa mites prior to attempting to install new queens and should target colonies that suffer queen loss with early treatments to control varroa.
Technical Abstract: The varroa mite (Varroa destructor) is very detrimental to honey bee, Apis mellifera, colonies that are not genetically resistant. Italian colonies are known to be susceptible to mites, and queen introduction has been reported to be more difficult in Italian colonies in recent years. This study compares supersedure rates in Italian colonies to infestation levels of V. destructor. Sixty-one Italian colonies divided into groups with comparatively high and low levels of infestation were observed for any queen changes during six weeks following the introduction of a mated queen. Colonies that had supersedure queens were smaller and had higher rates of mite infestation than colonies that retained their original queen. Supersedure and colony deaths were greater in colonies that were more highly infested.