Almost all other birds that arrived during winter have left the 15.59 sq km Nalabana inside the lake, said Divisional Forest Officer (DFO), Chilika Wildlife Division, B P Acharya.
The exact number of birds staying back will be clear only after summer census of birds in the third week of May, the DFO said. Around 7.19 lakh birds of 158 species visited Chilika last winter, official sources said.
It is not the first time that the birds stayed back during summer, said a noted ornithologist. "Since they stay in the lake even during summer, we may say that Chilika has become a home away from home for them," said ornithologist and retired forest officer Sudhakar Mohapatra.
The Flamingos and Pelicans will go to Kutch in Gujarat with the onset of monsoon for breeding and again come back to Chilika with other species before next winter, Mohapatra added.