Every year, in the Spring & Autumn, the research centre on bird migration organises studies and observations on birds. The Centre is part of the service of the Musuem of Natural History in Paris. The scientist catch the birds with nets and then band them. Once they are banded, they are immediately released. A complete record is kept in Paris, and when the birds return to the island of Ushant, the time of travel can be determined ushant by referring to the records.
Disclaimer: British Movietone is an historical collection. Any views and expressions within either the video or metadata of the collection are reproduced for historical accuracy and do not represent the opinions or editorial policies of the Associated Press.