Statistical News Release: Index of Abundance for Scottish Terrestrial Breeding Birds, 1994 to 2019

NatureScot has today released the latest figures tracking the abundance of Scotland’s terrestrial breeding birds.

Over the long term (1994-2019), the combined abundance for 66 species of terrestrial breeding bird increased steadily till the mid-2000s, and is currently 14% higher than in 1994 (using the smoothed indices). Since the mid-2000s the abundance declined to fluctuate between 14% and 17% above the 1994 index value.

Over the short term (2018-2019), using the unsmoothed indices, the ‘all species’, farmland, woodland and upland bird indices were stable, i.e. have not changed more than 5% since last reported.

Analysis of habitat specific trends did show some change over the long term: the woodland bird index increased by 59%; the farmland bird index increased steadily up to the late-2000s, and in 2019 it was 14% higher than in 1994; and upland birds decreased by 18% over the same period. The trends differ between species and may be due to factors on the breeding areas in Scotland or, for migratory birds such as whitethroat, conditions on migration routes or in wintering areas. Climate change is affecting some bird populations with evidence of birds shifting northwards (e.g. willow warbler).