European Birds Are Disappearing: Populations Down 20 Percent Since 1980

There are now 62 percent fewer European house sparrows than there were in 1980. Tomas Belka,

Good news: In many cases, efforts to protect rare European birds have helped stabilize and even increased the numbers of several feathery species.

Bad news: European birds in general are in significant decline, and some of the most common species, like house sparrows, are the hardest hit.

According to a study published this week in the journal Ecology Letters, the quantity of birds in Europe has declined by more than 20 percent in the past 30 years. While there were over 2.1 billion European birds in 1980, there are now around 1.6 billion, says study co-author Rich Inger, an ecologist at the University of Exeter in the United Kingdom.

Most of the decline—or 90 percent—is accounted for by a shrinking population in the 36 most common species, Inger tells Newsweek.

For example, throughout the continent there are now 62 percent fewer house sparrows (a common species also found in North America) than there were when Margaret Thatcher became prime minister, a decline of about 150 million animals, he says.

There were also drops in the numbers of such common species as skylarks, grey partridges and starlings.

The decline is likely due in part to habitat loss and pesticide use. The amount of land used for agriculture in Europe has greatly increased since 1980, and there are fewer places for birds to nest and find food, Inger says. At the same time, pesticide use has gone up, knocking down the number of "pests" like insects that birds prey upon, he adds.

"We don't manage the environment in a way that's good for birds," Inger says.

The study looked at an immense amount of data collected by thousands of "citizen scientists" over 30 years in most countries in Europe, in "an insightful departure from conventional approaches to reviewing bird monitoring data," said Michael Wunder, an ornithologist at the University of Colorado-Denver who wasn't involved in the study.

Wunder says the study clearly shows that "population sizes are most strongly affected by land use patterns" like farming. The measures used to protect rare species, like restrictions on hunting in certain areas, are not enough to prevent a decline in common birds, he adds.

If we want to protect birds in general, we need to change farming practices to provide more non-crop-laden land for birds, Inger says. Reducing pesticides would also help, as research has shown that areas with high pesticide use have fewer birds.

"What we can do is start..more environmentally friendly farming," Inger says. "We can leave wider margins on fields, get farmers to look after hedgerows, put up more bird boxes and provide places for birds to nest."