Reproduction of Varroa destructor in Africanized Honey Bees under the Tropical Conditions of Costa Rica

Varroa destructor is a worldwide ectoparasite of serious economic importance for beekeeping. Severe colony mortality is routine in parasitized European honey bees (EHB) colonies in Europe, Asia and North America. This study was carried out in Heredia, Costa Rica. The reproductive ability of varroa mites was determined approximately 240 h after cell sealing in worker brood from four Africanized honey bee (AHB) colonies and four hybrid (HF1) colonies. Several variables were measured for foundress female mites: fertility, production of a mature female mite, production of only immature offspring, production of only female or only male offspring and no reproduction at all. No significant differences were found between AHB and HF1 in the percentage of fertile foundress mites (X= 3.66, P= 0.06), the percentage of foundress mites that produced mature female offspring (X= 0.53, P= 0.47), and the percentage of APIACTA 42 (2007) 32 32 foundress mites that produced only immature stages (X2= 0.09, P= 0.75). However, the percentage of foundress mites that did not reproduce at all tended to be greater in AHB (30.2%) than in HF1 colonies (23.5%) (X= 3.66, P= 0.06). In both groups of bees, the number of fertile varroa mites was higher than what other studies have reported for AHB in Brazil. Nevertheless, a factor that limited varroa reproduction in AHB and HF1 colonies was the non-reproducing mites that we found in more than 23.0% of the worker brood cells.