Application and mechanisms of carbon dioxide as winter Varroa destructor control

Winter loss of honey bee (Apis mellifera L.) colonies is a significant concern for beekeepers. Among the identified causes for winter colony death, it is widely agreed that Varroa destructor (Anderson and Trueman) mites are the main predictor for which colonies can be expected to die before spring. As a result, proper control of Varroa mites is a fundamental part of successful beekeeping. However, mite control strategies are limited, with few chemical controls being recognized as both effective and safe for use in honey bee colonies, especially when honey meant for human consumption is involved.
Carbon dioxide is an established method of controlling arthropod pests within stored produce. It is possible, therefore, that increased CO₂ concentrations may serve as an option to control Varroa mites.
In this ongoing research, honey bee colonies (N=21 per treatment) have been exposed to altered atmospheres with increased carbon dioxide levels and compared with unmanipulated levels in an indoor wintering facility, while bee and mite mortality were monitored. This research aims to investigate the efficacy of carbon dioxide in winter control of Varroa mites.