Painted stork (Mycteria leucocephela) is a large resident wetland bird of stork family- Ciconidae and has been categorized as near threatened. A new nesting colony of wild Painted stork, breeding along with Lesser (Leptoptilos javanicus) and Greater Adjutant stork (Leptoptilos dubius) have been observed on the same nesting tree (Kadamb- Anthocephalus cadamba) at Bagritola village of Kadwa panchayat located on the flood plains of the Kosi river in district of Bhagalpur, Bihar, India. In October, 2015, a single nest and three Painted storks were observed (of which one bird was seen incubating) on a Kadamb tree in the village Bagritola. This breeding site was studied from October, 2015 to March, 2020 to observe the detailed nesting and breeding behaviors. From October, 2015 onwards a significant increase in the number of nests of Painted storks was recorded at the same breeding site and the storks adopted 2-5 separate but closely situated kadamb trees for nesting. In the month of September, 2017, two adjacent Kadamb trees were adopted by the Lesser and Greater Adjutant storks for nesting and they built two nests (one on each) Kadamb tree. In October, 2017, Painted storks also started to build their nest on the same trees which were already occupied by the Adjutant storks. From 2018 onwards, no nests of Lesser adjutant stork were observed and the Painted storks were found to breed along with Greater adjutant storks only, till the end of the study period i.e. March, 2020. Similar to the other two stork species, both the male and female Painted storks were sharing the process of nest building, incubation, nursing and guarding the chicks by rotation. Fragments of old branches of nearby trees as well as from abandoned nests were used for building the nests which were cushioned with the leaves. The Painted storks were successfully breeding along with the Greater adjutant storks on the same nesting trees peacefully without any obvious disturbances. The breeding season of Painted storks was observed to continue between October to March and their incubation period was estimated to range between 27-30 days. The breeding season of Lesser adjutant stork was observed to continue between mid-August to Feb whereas of Greater adjutant stork was observed between September to March with slight variation of 6-10 days in Bihar, India.

Greater adjutant stork (Leptoptilos dubios) is the largest and rarest stork belonging to the order Ciconiformes. It is one of the threatened bird species of the world and widely considered to be endangered. The present investigation was carried out to study the nest site selection, nest tree and other breeding behaviours of Greater adjutant stork on the flood plains of Kosi river in district Bhagalpur, Bihar, India in three breeding seasons from 2019 to 2021. Total 12 breeding colonies of Greater adjutant stork were recorded in 2019, 10 in 2020 and 2021 respectively. During these periods, 277 chicks were reared in 123 nests in 2019, 282 chicks in 126 nests in 2020 and 236 chicks in 105 nests in 2021 respectively. Most of the nest trees were located on the road side in and around the villages. Storks mainly selected Kadamb, Peepal, Pakar, Gamhar and Semel trees for the nest building but the Kadamb was the most preffered tree species. Nesting materials used by the GAS were mainly sticks, twigs and fresh leaves of Pigeon wood, Jalebia, Dhaincha, Jamun, Peepal, Gulmohar, Kadamb, and Semal tree. Nests were large spherical structure made of plant sticks mostly on the top of the tree and on the tip of large horizontal branches. Both the sexes alternately shared incubation and protection of the chicks after hatching. The parent birds also collected green leaves from nearby trees for cushioning the nest . The breeding season of Greater adjutant stork was recorded between September to April in Bihar. The incubation period was ranging between 37 to 39 days. Two to three chicks on one nest were common. The adult and juveniles finally vacated the nest before third week of April.