Where eagles dared
8 June 2012
Media and Communications Officer
Innovative new research has revealed the impact of human persecution and habitat destruction on Britain and Ireland’s native eagle species over a period of 1500 years.
The study, published in the journal Bird Study, indicates that both white-tailed and golden eagles were once found across large tracts of lowland and upland Britain and Ireland but populations plummeted as a result of human activity.
Using a combination of placename analysis, historic records and modern knowledge of the species’ ecology, researchers were able to estimate the former range and population of both eagles between 500 AD and the present day.
The resulting maps paint a sad picture of decline as golden eagle numbers dropped by two-thirds from 1000-1500 pairs in 500AD to 300-500 in 1800, while 80-90% of white-tailed eagles were lost over the same period.
Continued killing by humans eventually led to the extinction of the white-tailed eagle in the early years of the 20th century, while golden eagles still struggle in some parts of their range as a result of illegal killing.
Richard Evans, of RSPB Scotland and lead author of the study, said: “The results of this study are striking as they provide compelling evidence that eagles were widespread throughout most of Britain and Ireland in the Dark Ages. Between 500 and 1800 we see massive loss of eagle range in the south, which is consistent with the effects of habitat loss and killing by humans, rather than the influence of climate change on habitat, or competitive exclusion, as some have suggested.
“This trend continued in the years up to the First World War, until the only eagles left in all of Britain and Ireland were golden eagles in the highest hills and deer forests of Scotland.
“Recovery of golden eagles since this low point has now stalled, while limited recovery of white-tailed eagles has only been possible by reintroduction. Although the reintroduced white-tailed eagle (also known as sea eagle) population is healthy, at present they occupy only a fraction of their former range.”
RSPB Scotland Head of Species and Land Management, Duncan Orr-Ewing, said: “Reintroduction and other conservation efforts supported by many land managers are now attempting to restore our native eagle species across their former range. The results of this study will help to inform current and future eagle recovery programmes in the UK by improving our understanding of where these species should naturally occur in our landscapes.”
Commenting on the study, Environment Minister Stewart Stevenson said: “This informative study tells us much about the former distribution of eagles across Scotland. Birds of prey are an important part of Scotland’s biodiversity and our eagles are hugely popular with locals and visitors alike.
“The recent marked increase in sea eagles demonstrates how conservation and management efforts are beginning to make a real difference for these beautiful and iconic birds. The Scottish Government is also committed to working with our partners to tackle eagle persecution, with 2011 figures showing a welcome reduction in poisoning incidents for birds of prey.”
1. The abstract of the study is free to view on Bird Study’s website at: http://www.tandfonline.com/doi/abs/10.1080/00063657.2012.683388 . A full copy of the study can be e-mailed on request.
2. Table: Breeding population estimates (pairs) and estimated mean annual rates of population change (in brackets) since the preceding date for Golden and White-tailed Eagles in Britain and Ireland; 5000 BP to the present
Yalden & Albarella (2009)
Love (1983); D’Arcy (1998)
Love(1983); this study
Everett(1971); Brown (1976)
Dennis et al. (1984)
Eaton et al. (2003)
3. Reintroductions of white-tailed eagles are ongoing in the east of Scotland http://www.rspb.org.uk/ourwork/projects/details/274707-east-scotland-sea-eagles-esse
4. Reintroductions of both species continue in Ireland: http://www.goldeneagle.ie/ where white-tailed eagles are now breeding for the first time in 100 years: http://www.goldeneagle.ie/news_viewnews.php?z=132&news_id=11&article=306
5. In 2011, there were 57 pairs of white-tailed eagles nesting in Scotland.
6. Scottish Natural Heritage’s “Species Conservation Framework” for golden eagle, published in 2008, assessed the overall conservation status of the species in Scotland as “unfavourable”, with much of the eastern and southern parts of its range occupied only at low density, due to a range of factors, including illegal killing, and loss or deterioration of habitat caused by afforestation and over-grazing: http://www.snh.org.uk/pdfs/publications/commissioned_reports/Report%20No193.pdf
Maps: maps showing reconstructed range of eagles at 500, 1800 and 1920 AD are available. Please contact RSPB Scotland.