The reproductive ability of Varroa destructor in worker brood of Africanized and hybrid honey bees in Costa Rica
R A Calderon, M J Sommeijer, A de Ruijter, J W van Veen
From February to July 2001, the reproductive ability of Varroa destructor in artificially infested worker brood cells of Africanized honey bees (AHB) (Apis mellifera) and hybrids (HF1) of AHB x European honey bees was investigated in Costa Rica. No significant differences were found between AHB and HF1 in the percentage of fertile foundress mites (AHB = 69.8%, HF1 = 76.5%), the percentage of foundress mites that produced mature female offspring (AHB = 28%, HF1 = 25.4%), the mean number of offspring per foundress (AHB = 3.4, HF1 = 3.5) and the percentage of foundress mites that produced only immature stages (AHB = 17.3%, HF1 = 18.2%). Nevertheless, the percentage of foundress mites that did not reproduce at all tended to be greater in AHB than in HF1 colonies (AHB = 30.2%, HF1 = 23.5%; P = 0.06). In both groups of bees, the number of fertile varroa mites was higher than that reported in other studies for AHB in Brazil (49-55%). Furthermore, the percentage of non-reproducing mites was greater than the percentage reported for mites in European bees and lower than the percentage reported for mites in AHB in Brazil. Thus, the AHB population we monitored in this study may be less tolerant to varroa than AHB populations in Brazil.