GREENFINCH DOWN, CHIFFCHAFF UP

The 20th annual Birdtrends report has been published by the BTO. It highlights the rapid and continuing decline of the Greenfinch, down by 59% in the UK in just 10 years. It could now be Red List (which indicates the species of greatest concern) when it is next updated. The decline is caused by a widespread and severe outbreak of a disease called trichomonosis, which first affected bird populations in 2006. One species doing particularly well is the Chiffchaff, which is continuing to increase its breeding range and population thanks to warmer winters. The Birdtrends report covers 120 of Britain’s commonest and most widespread birds, from Mute Swan to Corn Bunting. The data covered in it was gathered by thousands of volunteer ‘citizen scientists’. Some count the birds they record on two early morning survey visits. The Breeding Bird Survey covers all habitats and volunteers are allocated a nearby square from a pre-selected list. Volunteer Alan Gomersall was initially disappointed not to get a square in the countryside but, after 20 years of recording in a Bedfordshire housing estate, says: “I am glad I continued, I have found a surprising number of different species over the years and it has been fascinating to see the changes; in 2003, I counted 50 Greenfinches, this year they were down to just five.” The report is produced in partnership by the BTO and the Joint Nature Conservation Committee (JNCC). To see it, go to: