BirdTrends 2018: trends in numbers, breeding success and survival for UK breeding birds

The 21-year BBS trend for Swift (the longest trend available for this species)
rasies a high level alert in this reoprt.

Key findings

Species list

Using the BirdTrends pages

The BTO's BirdTrends report is a one-stop shop for information about the population status of the common breeding birds of the wider UK countryside. The report is based on data gathered by the many thousands of volunteers who contribute to BTO-led surveys.

For each of 121 species, users can quickly access the latest information on trends in population size, breeding performance and survival rates, as measured by our long-term monitoring schemes. For each species, you will find:

  • The latest conservation listings and estimates of UK population size
  • A summary of changes in the size of the population and the possible causes of these changes
  • Graphs and tables showing changes in UK population size, breeding performance and survival since our monitoring began
  • Wherever possible, graphs and tables separately for UK countries (England, Scotland, Wales and Northern Ireland)
  • Alerts, drawing attention to population declines of greater than 25%, or greater than 50%, that have occurred over the the most recent five-, ten- and 25-year assessment periods and the maximum period available (usually 49 years).

Text, tables, graphs and presentation for each species are updated annually to include the latest results alongside interpretative material from the literature. Information on demographic trends and on the causes of change is gradually being expanded.

There is far more to this report besides the species pages! Supporting pages describe the field and analytical methods that were used to produce the results for each species and to identify alerts. We discuss overall patterns of trends in abundance and breeding success, and compare the latest trend information and alerts with the Birds of Conservation Concern list, last updated in 2015 (Eaton et al. 2015). Summary tables list alerts and population changes by scheme, and you can use our 'table generator' to select and display tables of population change to your own specification. A detailed References section lists more than 820 of the most relevant recent publications, with onward links to abstracts or to full text where freely available, and is a valuable key to recent scientific work by BTO and other researchers.The Key findings page provides a brief overview of our main findings this year.

We would value your comments on this report and particularly any suggestions on how it can be improved:

info [at] (Email your comments)


These web pages constitute an annual report that is part of the BTO Research Report series. Authors were Ian Woodward, Dario Massimino, Mark Hammond, Sarah Harris, Dave Leech, David Noble, Ruth Walker, Carl Barimore, Daria Dadam, Sarah Eglington, John Marchant, Martin Sullivan, Stephen Baillie and Rob Robinson. The recommended citation for the report is as follows, and is given in the page footer throughout the report:

Woodward, I.D., Massimino, D., Hammond, M.J., Harris, S.J., Leech, D.I., Noble, D.G., Walker, R.H., Barimore, C., Dadam, D., Eglington, S.M., Marchant, J.H., Sullivan, M.J.P., Baillie, S.R. & Robinson, R.A. (2018) BirdTrends 2018: trends in numbers, breeding success and survival for UK breeding birds. Research Report 708. BTO, Thetford.