The effects of methyl parathion on the colony dynamics of Apis mellifera : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University, Palmerston North, New Zealand

Abstract

The detrimental effects of pesticides to honey bee colonies were assessed using a combination of electronic and manual sampling techniques. Initial experiments determined that electronic bee counters could be used to identify and monitor toxic events occurring in honey bee colonies, and also identified that 30 minutes after application, the bees did not avoid direct contact with methyl parathion. Dead bee counts, flight activity, percent return of foragers, and determination of colony composition were used to assess the effects of methyl parathion on the colony dynamics of Apis mellifera. In particular, the combination of dead bee counts, colony composition analysis, and "real time" data, provided an extensive monitoring system that enabled the progression of colony recovery to be followed, and generated information of use for the application of pesticides in the local environment. The analysis of colony composition identified that brood declined in response to decreased worker bees, and that colony recovery was dependent on brood and food reserves within the hive. The foraging activity of honey bee colonies dosed with methyl parathion was lower than that of untreated colonies because their flight activity and percent return rate declined for at least six weeks following methyl parathion application. Keywords: Honey bees, Apis mellifera, Pesticide effects, Methyl parathion, Flightmonitoring