An Official Statistics Publication for Scotland: Index of Abundance for Scottish terrestrial breeding birds, 1994 to 2024

Over the long-term (1994-2024), the combined abundance for 66 species of terrestrial breeding bird increased steadily till the mid-2000s before declining until the early 2010’s. The index has since stabilised and is currently 12% higher than in 1994.

Over the long-term (1994-2024), habitat-specific trends show that the farmland, urban and woodland indices have increased (+10%, +26%, +66% respectively), whereas the upland index has decreased (-19%).

Over the medium-term (2014-2024), the all-bird index, upland and woodland indices have remained stable (i.e. have not changed more than 5%). The urban bird index has increased (+6%) and the farmland bird index has decreased (-5%) since 2014. 

A breakdown of farmland habitats shows a long-term (1994-2024) increase in pastoral and wooded farmland indices (+24% and +7% respectively) and decrease in arable, wet farmland indices (-12% and -26% respectively). However, the medium-term trend (2014-2024) is decreasing for all farmland habitats: arable, pastoral, wet farmland and wooded farmland (-17%, -8%, -21% and -12% respectively) 

The trends differ between species and may be due to factors in the breeding areas in Scotland or, for migratory birds such as Swifts, conditions on migration routes or wintering areas. Climate change is an important factor in bird abundance in Scotland, as shown by the close relationship between the bird abundance trend and Scotland’s mean annual temperature. Increased temperatures and summer rainfall, both outcomes of climate change, are impacting food availability of birds like Capercaillie and Golden Plovers.