Bird populations across Europe have fallen by around 600 million in the past 40 years, according to a report exclusively shared with Channel 4 News.
One in six birds have been lost since the 1980s, the joint study by the Royal Society for the Protection of Birds (RSPB) and BirdLife International found, as its authors called for action to “reduce the threat of extinctions… for the sake of nature and people”.
The study, which has been seen by Channel 4 News and will be published in the Ecology and Evolution journal on Tuesday, found the main reason for falling bird populations is food production and farming methods.
Professor Richard Gregory, the head of monitoring at the RSPB, said: “Farmland across Europe has become much more inhospitable to bird populations and other wildlife.
“The loss of these common and abundant species has cascading effects upon the ecosystem where systems are changing so rapidly that they won’t be able to sustain us, they won’t be there to provide our food, to regulate our climate. And the birds are that warning signal.”
Scientists analysed data for 378 out of 445 bird species native to countries in the EU and the UK.
From 1980 to 2017, the study estimates some 900 million birds have been lost, but there has also been an increase of 340 million in certain species leaving a loss estimated to be between 560 million and 620 million.
The largest decline was among birds associated with agricultural land and grassland.
The House Sparrow population has plummeted by 247 million, the number of Yellow Wagtails across the continent has fallen by 97 million, Starling numbers are down by 60%, around 75 million, and Skylarks have decreased by 68 million.
Ornithologist John Callion said: “I feel angry about it – that we’re in a position where we’ve let wildlife get to such a state.
“We are responsible for this, they depend on us, and if they go we’ll follow them soon.”
Much of the decline in bird numbers occurred during the 1980s and 1990s, but it continues to this day.
The study was compiled using data from the European Bird Census Council’s Pan European Common Bird Monitoring Scheme, and mandatory reporting by EU Member States to the European Commission under the EU Birds Directive.
Young climate activist Morgan Guthrie, who was at the COP26 conference in Glasgow, said: “This is going to change our world without these creatures. We’re in the middle of a sixth mass extinction. We don’t know what’s coming and it’s really really scary.”
The State of Nature report, compiled by scores of environmental organisations and research institutes in 2019, found that more than one in seven species in the UK are at risk of extinction.