Populations of honeybees pollinating sunflower crops on the central Darling Downs, Queensland

Abstract

Populations of honeybees pollinating flowering sunflower heads in 42 fields on the central Darling Downs were recorded. Mean populations ranged from 21.9 to 171.2 bees per 100 flowering heads. A calculated maximum requirement for the region during fine weather amounted to 24 bees per 100 flowering heads. Populations were positively correlated with number of hives within 3 km of fields. In 18 fields with no hives within 3 km, mean populations (apparently from feral colonies) ranged from 21.9 to 130.9 bees per 100 flowering heads. These populations showed no significant correlation with area of crop in the range 2-95 ha. In another study on the central Darling Downs, seed set was not significantly correlated with number of hives within 3 km, indicating that feral bee populations were adequate for sunflower pollination.