He said migratory birds come in September and October, and sometimes in August; but climate change has caused seasons to begin earlier or later on different occasions.

“This year, we have an early start to the migration season, “he said.Sri Lanka is home to 435 bird species, including 110 migratory species, accounting for 26% of total birds, according to the Conservation of Migratory Species of Sri Lanka.

Over the years the number of vagrants-birds roaming outside of their typical breeding areas has increased, Dr. Gunawardana noted, with birds coming from Siberian areas, neighbouring India and Mongolian regions.