Nesting plants, nesting height selection and bee flora of Apis dorsata Fab. (Hymenoptera, Apidae) in selected districts of south Karnataka, India

Apis dorsata is well distributed in the Indian subcontinent for rich availability of floral resources along with suitable nesting structures. Nonetheless, the nesting structures and floral resources vary from hilly regions to plains seasonally. Regular field studies were conducted on major nesting plants, nesting height selection, and major bee flora of A. dorsata in the plains of South Karnataka, India, during 2021-2024 at fortnight intervals. The results showed that A. dorsata selected 12 major plant species for nesting and among them, a few were Ficus bengalensis, Terminalia arjuna, Delonix regia, F. religiosa, Samanea saman, and Eucalyptus nilgiris. Furthermore, A. dorsata selected heights range between 10 and 20m above ground level for nesting in greater numbers. Similarly, A. dorsata workers gathered pollen and nectar from 43 major bee flora in the study regions. The major pollen flora recorded were coconut, mango, papaya, coriander, etc. Similarly, the major nectar flora identified were eucalyptus, pongamia, drumstick, tamarind, and neem. However, acacia, mustard, pigeon pea, lemon, guava, and jamun produced both pollen and nectar for A. dorsata colonies. The study concludes that A. dorsata is well adapted to the plains of South Karnataka by nesting on suitable tree plant species at an ideal height for the rich availability of floral resources. Nevertheless, nesting structures and floral resources play a crucial role in the successful establishment of A. dorsata colonies.