Spatial aspects of foraging behaviour in Eastern honeybees, Apis cerana

Abstract

The majority of plants in Asian tropical ecosystems depend on bee pollination. However, there is a substantial lack of knowledge of the behaviour and ecology of native tropical bees. In the present study I explored how the Eastern honeybee, Apis cerana, distributes its foragers in the local environment analysing waggle dances of foragers in four rural and urban locations in Kerala, South India. Similar to their well-studied close relatives, the Western honeybee A. mellifera, returning A. cerana foragers recruit nest mates through these dances communicating the distance and direction from the hive to a food source. I decoded the locations of food sources for which pollen and nectar foragers danced. The results suggest that the bees tend to forage over shorter distances as compared to the Western honeybees. Furthermore, I have found that the foraging distances, in which dancing foragers have travelled, can notably differ for pollen and nectar resources. However, there is no significant difference in the direction in which nectar and pollen foragers travel. The results also show that despite floral abundance in the proximity of the hive in the rubber plantation, foragers travelled significantly further in this location when compared to the distance that they travelled in the other locations. This may indicate that these floral resources might actually represent a nutritionally poor floral resource for the honeybees. Throughout all of the four locations, the honeybee colonies showed variable patterns of foraging distribution, focusing their recruitment towards areas which seemed to offer both pollen and nectar rewards. This is likely to be in response to the spatial clustering of their food sources, which may be a characteristic of landscapes that are dominated by human agri- and horticultural activities.