Sudbury’s resident swans are being tagged as part of a study into the birds’ behaviours.

Last week, volunteers from the East Anglian Swan Study group visited Brundon Mill on the outskirts of the town, where scores of the birds congregate, to put identifier rings on their legs.

This will enable each swan to be identified so researchers can track individual life histories and build up knowledge.

The group has marked more than 2,000 swans across East Anglia and the Home Counties since it started its work six years ago.

Group leader Mike Reed said: “Because mute swans live a relatively long time – up to 30 years in some cases – this is a long-term project and the group expects to operate for between 10 and 15 years before it is able to confirm its theories and corroborate the results.”

However, even in these early stages some findings are emerging.

Mr Reed added: “We’ve found that most mature mute swans do not go very far at all.

“Youngsters and sub-adults tend to travel a bit further afield – within a vicinity of 10-15 miles – and often between two sites. We think this is to do with the birds getting to know their area and building up a mental map.

“Occasionally, we do find a mute swan that has travelled a long distance. One bird from the east was recently recorded in Yorkshire.”

People who spot ringed birds are encouraged to e-mail in brief details of the time, date and location of the swan and its four-digit identifier, along with any significant information. In return they will be e-mailed back details of the life history of the bird.

To find out more about bird ringing visit the BTO website or to report a mute swan with a ring, email Mike Reed