Inter-colonial nesting features of few migratory birds amidst few distinct agro-climatic landscapes of Southern Karnataka, India

The Oriental white ibis (Threskiornis melanocephalus), spot-billed Pelican (Pelecanus philippensis) and Painted stork (Mycteria leucocephala) and are migratory birds nest on specific giant trees amidst rural and urban landscapes. Despite their unique and elite nesting strategy and colonial nesting, these bird species are facing threats due to various anthropogenic activities. T-Published reports on nesting ecology of these bird species are poor. In the present investigation, systematic field observations were made using various standard methods with the help of scientific binocular and camera during 2021 to 2023. Data indicated quite interesting results. The T. melanocephalus, P. philippensis and M. leucocephala and T. melanocephalus shared their nesting platform on well canopied giant tall trees such as Samania saman, Vachellia nilotica, Tamarindus indica, Ficus bengalensis, Thespesia populnea and Muntingia calaburau. On different canopies of these tree species, P. philippensis, M. leucocephala and T. melanocephalus live by establishing separate territory. They chose distant locations away from human inhabited places, water source and road ways which were statistically varied considerably among the nested sites of these bird species. Moreover, their foraging habit although different, but shared common foraging grounds sometimes. Interestingly, flock size, number of flocks, number of nests established on different tree species and preference of tree species for nesting varied considerably among migratory bird species. All these differential attributes of T. melanocephalus, P. philippensis and M. leucocephala indicated specific nesting environment for their safe survival. Hence, it is high time to protect these migratory birds, as they contribute much to the local environment to help eradicate the pests and certain harmful insects in agricultural ecosystems. Thus, migratory birds and their nesting sites preservation are essential and accordingly certain mitigation measures to restore these species are required. Results of such investigations will be published elsewhere.