Swallows, traditionally considered the harbingers of summer in Finland, have been seen as far north as Rovaniemi, the capital of Finnish Lapland, reports Birdlife Finland. House martins have also been spotted near the Arctic Circle.
Ornithologists on bird towers have counted thousands of arriving finches, siskins and thrushes. The lucky have also observed various hawks and storks.
Among the rarest sightings have been a ring-necked duck in Uusikaupunki on the west coast and a ferruginous duck in Hamina on the south-east coast.
First sightings on Monday included a red knot in Pori as well as a whitethroat and a citrine wagtail in Kirkkonummi.