Abundance decline in the avifauna of the European Union conceals complex
patterns of biodiversity change
Abstract
While global assessments provide evidence of biodiversity decline, some
have questioned the strength of the evidence, with local assemblage
studies often showing a more balanced picture of biodiversity change.
The multifaceted nature of biodiversity and imperfect monitoring
datasets may partially explain these findings. Here, using an extensive
high-quality dataset, we find significant biodiversity loss in the
native avifauna of the European Union (EU). We estimate a decline of
17-19% in overall breeding bird abundance since 1980: a loss of 560-620
million individual birds. Both total and proportional declines in bird
numbers are high amongst species associated with agricultural land. The
distribution of species’ population growth rates (ln) is centred close
to zero with numerical decline driven by substantial losses in abundant
species. Our work supports previous assessments indicating recent
biodiversity loss and calls to reduce the threat of extinctions and
restore species’ abundances, for the sake of nature and people.