Infestation levels and control of the Varroa mite ((Varroa destructor) in managed honey bee colonies from selected agro ecological zones of Uganda

Abstract

The Varroa mite, Varroa destructor (Arachnida: Acari: Varroidae) is an ectoparasitic mite of the honey bee (Apis mellifera). It was first detected in East Africa in 2009. Currently, no control strategies have been put in place to manage the pest in Uganda. A study was conducted to establish the extent of spread of the Varroa mite, determine its seasonal population dynamics and also evaluate some control options against the mite using Varroacides. A survey of nine districts representing four Agro ecological zones of Uganda in November and December 2015 showed that Varroa was present in all. Severity of infestations calculated as Varroa load (number of mites per 100 bees) was below the threshold of 5 mites per 100 bees. An average of 4±0.69 mites were recovered per colony sampled. Altitude, seasons (dry and wet), AEZ had no effect on Varroa mite populations. There were significant differences in the comparative efficacies of two varroacides. Fluvalinate had a higher efficacy (59.65%) than Thymol (38.79%) though both values were generally lower than those that have been reported elsewhere. Effects of the treatments on some colony performance parameters (flight activity and number of combs with honey) were found to be insignificant while they were significant for brood characteristics (brood pattern and number of brood combs). This is an indicator that further studies should be done to establish the effect of these treatments on brood and also the queens within hives. Also, an integrated management approach for the mite should be developed to avoid dependence on chemicals which can result into development of resistance of the mite.