In this discussion we:
- Review the latest population change measures and alerts for species that are on the Birds of Conservation Concern (BoCC3) red or amber lists for the UK for reasons of population decline (Eaton et al. 2009) (here).
- Identify species not on the BoCC3 lists but which raise alerts on account of long-term declines and, conversely, currently listed species where recovery may be sufficient to downgrade their listing status in the future (here).
- Briefly review declines along waterways and in scrub and wetland habitats as shown by the WBS/WBBS and CES schemes (here).
- Review trends over the last 10 years in species that have shown long-term declines, to identify the extent of ongoing declines and check for any evidence of recovery (here).
- Identify those species that have shown rapid long-term population increases (here).
- Discuss patterns of changes in breeding performance and relationships between trends in abundance and breeding performance (here).
- Summarise the overall patterns found (here).
Except where otherwise indicated, our discussion is based on the best long-term trend that is available for each species. These are the trends presented as the main trend graph for each species. Details of estimating and comparing trends are given in the methods section. Full details of all trends available for each species are given on the species pages. Summary tables of all alerts raised by each scheme are presented in the summary tables.
It should be noted that a number of species included in the BoCC3 red and amber lists are not covered by this report, and that not every species listed amber is in UK decline. Thus tables relating to red or amber list status do not include every species so listed.
This report should be cited as: Baillie, S.R., Marchant, J.H., Leech, D.I., Renwick, A.R., Eglington, S.M., Joys, A.C., Noble, D.G., Barimore, C., Conway, G.J., Downie, I.S., Risely, K. & Robinson, R.A. (2012) BirdTrends 2011. BTO Research Report No. 609. BTO, Thetford. http://www.bto.org/birdtrends