Surveillance of synthetic acaricide efficacy against <i>Varroa destructor</i> in Ontario, Canada

Abstract The parasitic mite Varroa destructor (Mesostigmata: Varroidae) is the main culprit of honey bee (Hymenoptera: Apidae) colony mortality in Ontario, Canada. Most beekeepers use synthetic acaricides to control V. infestations their colonies, but these products increases risk developing resistance active ingredients, which a growing concern. This study sought determine efficacy three approved for Canada infestations, amitraz (Apivar™), tau-fluvalinate (Apistan®), and flumethrin (Bayvarol®), using Pettis test. rate populations differed tested. Amitraz caused significantly higher (92%) than (78%) (72%) did. was classified as “mostly effective” (90–97%), whereas were “minimally (&lt; 80%) studied. Variation due acaricide exposure observed between apiaries regions. results highlight importance periodically assessing varroacidal activity inform decisions parasite when implementing integrated pest management strategies.