A quarter of the birds here have disappeared

In Europe, it's well documented that bird species associated with agricultural landscapes have experienced a sharp decline over several decades. 

Since 1980, populations have been reduced by around 60 per cent. 

New Norwegian figures show that the same negative trend is also taking place in Norway.

The bird index shows a decline for many species

The Norwegian monitoring programme for agricultural landscapes, commonly known as 3Q, has been run by NIBIO since 1998. 

Researchers track land use, landscape changes, and how these affect biodiversity.

“We have monitored breeding birds in the agricultural landscape for 25 years,” says NIBIO researcher Christian Pedersen. 

To summarise the results, the researchers have calculated a dedicated bird index.

In total, there are around 34 species that live mainly in agricultural landscapes – so-called farmland birds. 

Not all are equally common or have the same distribution. The researchers have therefore selected the 22 species that are common enough to provide a reliable picture of trends over time.

Since the 3Q monitoring began in 2000, that year serves as the reference point (index value = 100). 

Since then, the results show a steady and clear decline throughout the entire period. 

In 2023, the bird index had fallen to around 75 – a reduction of about 25 per cent since monitoring began.

Some species are increasing, but most are declining

Pedersen explains that there is some variation between species, but several common species have experienced a particularly strong decline.

“The fieldfare has declined by as much as 56 per cent, while populations of the common swift, yellowhammer, and whinchat have been reduced by around 50 per cent," he says.

Pedersen adds that at the same time, some species, such as the Eurasian tree sparrow, house sparrow, and starling, show a moderate increase of about 15 per cent.

“The species showing the strongest increase is the European goldfinch, whose population has grown by as much as 54 per cent since 2000,” he says.

Several reasons behind the decline

It's important to remember that there are large differences between the bird species found in the agricultural landscape. 

They have different preferences and ways of life. It's therefore not possible to point to a single cause explaining why so many species are declining. On top of that, climate change may also play a role.

Pedersen notes that some of the 22 species are resident birds that are present in Norway all year round. Others are migratory birds that overwinter farther south in Europe or in Africa. 

He says it's hard to determine with certainty how much of the decline is caused by factors in Norway, versus conditions along migration routes or in wintering areas.

“However, the fact that we also see declines among species that remain in Norway all year means that we must take a large share of responsibility for what's happening here,” he says. 

Pedersen adds that cooperation across national borders also need to be strengthened.

Changes in land use are the main explanation

According to the researcher, it's primarily historical and ongoing changes in the landscape's content and use that explain the decline. 

When agricultural landscapes become more uniform, important habitats for many bird species disappear.

Pedersen explains that field margins, small woodlots, pastures, wetlands, and small habitat features provide food, shelter, and nesting sites. 

"When these landscape elements disappear, the basis for bird life is weakened. In addition, some species nest directly on farmland and are therefore in direct conflict with food production. This applies, for example, to the northern lapwing, Eurasian curlew, and skylark,” he says.

For these species, more intensive farming is particularly challenging, for example when farmers extend the growing season by cutting hay more often.

Increased drainage also poses a challenge.

Measures can reverse the trend

The results from the 3Q programme provide an important knowledge base for management and agricultural policy.

To slow down and eventually reverse the negative trend, the researchers recommend the following measures:

• Preserving and facilitating habitats to ensure access to food and shelter.
• Adapting farming practices to the birds’ life cycle.
• Protecting field margins, small woodlots, and wetlands.
• Managing grazing areas and hay meadows.
• Reducing the use of pesticides.
• Preventing overgrowth and planting with coniferous forest.

Several existing environmental subsidy schemes that were originally established for other purposes may already have a positive effect on birdlife. Pedersen notes that some schemes could perhaps be adjusted to strengthen the effect.

A symptom of something bigger

“When bird populations decline, it's often a signal of more fundamental changes in nature,” says Pedersen. 

Birds are high up in the food chain. They respond quickly to changes in living conditions. They are therefore important indicators of environmental status and ecosystem health.

Fewer flowering plants lead to fewer pollinating insects – and thus fewer birds.

“Unfortunately, the negative trend does not appear to be reversing anytime soon. That's why it's urgent to implement measures that can help bird populations increase, or at least stabilise,” he says.

Reference:

Pedersen, C. & Alemu, D.T. Fuglenes bestandsutvikling i det norske jordbrukslandskapet 2000–2023 (Bird population trends in the Norwegian agricultural landscape 2000-2023), NIBIO POP, 2026. DOI: 10.21350/1v8m-rb02

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