Every autumn, thousands of birds migrate from breeding grounds in the Russian Arctic. Many of them come south to winter at the Wildfowl and Wetlands Trust sites at Welney in Norfolk and Slimbridge, while others take to the Pacific flyway, and make for the remote wetlands of the Rio Grande in New Mexico. The BBC’s Natural History Unit is broadcasting a series of live programmes to follow the exodus and chart the progress of a flock of Bewick’s swans as they make their way to Welney, via Estonia and the Netherlands. Live satellite link-ups with New Mexico will be tracking snow geese and sandhill cranes to their final destination.

The programmes will explore the mysteries of migration with the help of two particular swans, Abelhard and Pedro, who have been fitted with tracking devices. At the time of going to press, Abelhard has disappeared and it remains to be seen whether she is still alive, or whether her beacon has become detached.

The series is interactive and each day schools are invited to put questions to the presenters (both here and in New Mexico) live on air, or via the Internet or e-mail: Swanline, 0891 339980 (lines open on Monday November 18 at 10. 00am and close on November 24 at 10.00pm) By Internet: http:www.bbc.co.uk heading-southBy e-mail: heading.south@bbc.co.uk