A report published by the British Trust for Ornithology has assessed the impact that climate change has had in driving population changes in the UK over the last 25 years. Species’ responses to climate change, temperature and rainfall were analysed to provide the most comprehensive synthesis of the likely future impacts of climate change on UK and Irish birds to date.
For example, an increasing body of research demonstrates that within the UK, breeding seabirds and upland breeding birds are the two groups most vulnerable to climate change. Fourteen seabird species are regarded as being at risk of negative climate change impacts. These include Puffin, for which a population decline across Britain and Ireland of 89% is projected by 2050.
Conversely, the results also show beneficial effects whereby, changes in climate appear to be contributing to population increases and expansion in breeding waterbirds, including species colonising from continental Europe. The report finds that waterbirds with a southern distribution, coastal and heathland species are those most likely to benefit from climate change. However differential responses to climate change across breeding and wintering grounds mean that the climatic drivers of migratory bird populations may be more complex than those of resident species.
Overall, a quarter of our breeding species appear to be negatively affected, and a quarter may be responding positively; the remaining breeding species that have been studied appear relatively unaffected by climate change. Warmer spring temperatures can increase breeding success, whilst a reduction in winter severity has boosted annual survival of many resident species.
Despite the findings, there is a lack information about the extent to which climate change might be driving population trends of our breeding bird species. Many of the UK and Ireland’s bird populations are swelled by large numbers of individuals that arrive from elsewhere in the autumn to spend the winter here. Yet, the wintering populations of only 28 species have been subject to studies of the impacts of climate change, and it is essential that we address these significant gaps in our knowledge.