The RSPB will increase its surveillance of wild birds on its wetland nature reserves in Dorset, Devon and Somerset in response to the news that the avian flu virus H5N1 has been detected in mute swans from the Abbotsbury Swannery in Dorset.

Dr Mark Avery, the RSPB's Director of Conservation, is clear that vigilance is the first priority: 'Since H5N1 bird flu first appeared as a threat to birds in the UK, the RSPB has been at the forefront of monitoring wild birds - this vital work will continue'.

'Frustratingly we are facing yet another outbreak of bird flu, this time the circumstances are consistent with the disease arriving in wild birds. Worldwide, this virus has been transmitted via a variety of routes only one of which is through the movement of wild birds. Other include poultry movements, direct human transfer and the wild bird trade, now banned in the European Union'.

'We simply don't know how this virus has arrived in Dorset; it is unlikely to have involved the swans directly as this population is highly sedentary'.