Breeding biology of the Spot-billed Pelican (Pelecanus philippensis) in Karaivetti Bird Sanctuary, Tamil Nadu, India

The breeding biology of the Spot-billed Pelican (Pelecanus philippensis) was investigated from September 2007 to September 2010 in Karaivetti Lake, Tamil Nadu, India. The Spot-billed Pelican breeds between November and April at the Karaivetti Lake. It also breeds roughly during the same period at other breeding sites in Tamil Nadu, except for the Vedanthangal and Karikili bird sanctuaries, where pelicans arrives much earlier and their breeding activities start and end to some extent ahead of the other sites, i.e., from September to March. In essence, the breeding season starts after the onset of the northeast monsoon in Tamil Nadu. A few days after their arrival, pelicans perform courtship display, form pairs, start nest construction and lay eggs. Courtship display is not as attractive and impressive as in other waterbirds. The clutch size varies from two to three eggs and the incubation period from 25 to 36 days. The fledging period varies from a minimum of 90 to a maximum of 102 days. The nest success rate of the Spot-billed Pelican at Karaivetti was 90.28% during the study period.