Susceptibility and mortality in honeybees (Apis mellifera) infested with the tracheal mite (Acarapis woodi)

Abstract

The tracheal mite, Acarapis woodi (Rennie), is an obligate parasite of the honeybee. It was first discovered in 1919 by Rennie during his investigation into the widespread deaths of honeybee colonies in Europe in the early 1900s, later known as the 'Isle of Wight' disease. While the mite has been associated with honeybee colony mortality since that time, there is still no consensus that tracheal mite infestation was the cause of the Isle of Wight disease or that tracheal mites can cause colony mortality. In previous research it has been shown that mites transfer from old to young host bees via body hair, that this migration is limited to very young bees (normally less than 4 days old) and that bee strain affects susceptibility. This thesis contains an investigation into infestation of honeybees by tracheal mites and considers the factors that determine susceptibility and mortality in colonies.