Effect of the Colony Densities of Apis mellifera on the Foraging Behavior of Apis cerana

PurposeIn this study, we compared the changes of the foraging behavior of Apis cerana under various colony densities of A. mellifera at Luoping in the florescence of Brassica campestris. In order to provide scientific basis for rational protection of native bee species and maintenance of plant community structure and stability from the perspective of competition for food resources.

MethodSix field sites from Jiulong Town and Dashuijing Town were selected for placing experimental eastern honeybee colony based on the previous survey of colony density of western honeybee. Firstly, the number of foragers for these two honeybee species was counted, and the frequency of visiting flowers and the average settling time for A. cerana was recorded under farmland and montane habitat of these experimental sites. Secondly, species of phanerogam within three kilometers were investigated, and anthers of phanerogam, pollen grains of A. cerana were collected to calculate the proportion of various pollens. Finally, effects of various colony density of A. mellifera on the foraging behavior and pollen collecting of A. cerana were estimated.

ResultsThe quantitative proportion of A. cerana in the mountain forest was higher than that in farmland quadrats for six experimental sites in the flourishing florescence, but the quantitative proportion of A. cerana in farmland quadrats was increased significantly after A. mellifera apiaries evacuating from Luoping at the end of flowering stage. There were significant positive correlation between the average visiting frequency of A. cerana and colony densities of A. mellifera within 3 km, and the significant negative correlation between the average settling time of A. cerana and colony densities of A. mellifera within 3 km; with the increase of the colony densities of A. mellifera in the mountain forest, the visiting frequency of A. cerana increased, the settling time of A. cerana reduced; there were negative correlation between the total number of pollen loads collected by A. cerana and colony densities of A. mellifera within 3 km; there were significant positive correlation between the percentage of wild pollens collected by A. cerana and colony densities of A. mellifera within 3 km.

ConclusionThe colony density of A. mellifera has a significant effect on the foraging behavior of A. cerana. With the increase of the colony density of A. mellifera, the more the food niche of A. cerana deviate the source of large amount of pollen plants in farmland, and the trend which foraging area of A. cerana was shifted from the farmland to the mountains forest become more obvious.