Concern over disappearing greenfinches
The species was not considered under threat when the UK’s conservation priorities were last updated two years ago, but experts say the once-familiar garden bird could end up red-listed as at risk of extinction if the current trend continues.
The decline has been caused by a widespread and severe outbreak of a disease called trichomonosis, which first hit populations in 2006.
Kestrels are also faring badly in Scotland, showing a 59 per cent decline in the last 10 years, while curlews have fallen by 69 per cent in the past 20 years.
But the survey results also show encouraging changes for some species.
Chiffchaff numbers, for instance, have taken off. The poll shows the small green warblers have increased more than sixfold since 1995.
It’s thought the species is benefitting from warmer winters, a result of climate change. Once a very rare sight in winter, the birds can increasingly be seen on sunny days in sheltered locations throughout the nation, particularly in milder coastal areas and around inland water bodies.
Great spotted woodpeckers and blackcaps are also doing better, with numbers having more than quadrupled north of the border since 1995.
The BTO’s annual report brings together data collected by ornithologists and thousands of volunteers across the nation. BirdTrends covers 120 of the UK’s commonest and most widespread birds and is a valuable tool in assessing their fortunes.
The BTO’s Dr Rob Robinson, who helped produce the findings, said: ”This report presents the results of many thousands of hours by volunteers looking out for birds in every habitat – from the streets of Cambridge to the slopes of the Cairngorms. It is only thanks to their effort we know so much about the health of our bird populations.”
Dr Dario Massimino, lead author of the report, added: “Each year I am able to bring together information from six of the BTO’s core surveys in order to produce the thousands of graphs and tables which the BirdTrends pages are composed of.
“It is exciting to be one of the first people to get the full picture of the trends of the 120 species included in the report.”
Andy Coates, who operates one of Scotland’s longest-running constant survey sites, near Edinburgh airport, said: “We’ve really noticed the increase in chiffchaffs in the last few years.”