Half of Scotland’s Wrens lost in recent cold winters

No.:  2011-29
July 2011

Issued by BTO on behalf of BTO, JNCC and RSPB

Harsh winters have devastated Scotland’s Wren population – latest figures from the BTO/JNCC/RSPB Breeding Bird Survey (BBS), released today, show that numbers fell by 40% between 2009 and 2010.

Wren by John Harding 

Wrens lose body heat very easily

As one of Britain’s smallest birds, Wrens lose body heat very easily. During cold winters they are known to roost huddled together for warmth, but, despite this, mortality during harsh weather is often high. Fortunately, they are also able to reproduce very quickly, so numbers often bounce back when conditions improve.

Numbers of Stonechats also fell by 77% between 2009 and 2010, following several years of increases – presumably also due to cold winters.

Wren and Stonechat are just two of the 60 species monitored by the BBS in Scotland, and the latest figures also show that two amber-listed upland birds, Meadow Pipit and Curlew, have fallen to their lowest levels since the start of the survey, showing declines of -31% and -53% respectively since 1994. However, a number of other species are doing better in Scotland than in the rest of the UK, including the red-listed Tree Pipit (+51% since 1994), House Martin (+114% since 1994) and the amber-listed Willow Warbler (+21% since 1994).

Kate Risely, BBS organiser at the British Trust for Ornithology, commented, “Bad weather can have a really severe impact on bird numbers, and many birdwatchers in Scotland have noticed the decline in Wren numbers. The BBS allows us to accurately measure these changes, and we’ll be keeping an eye on the trends to see if numbers recover in future.”

Dr Andy Douse, Ornithological Policy & Advice Manager at Scottish Natural Heritage, added “The 2010 BBS report yet again highlights the tremendous contribution made by volunteers to bird recording in Scotland. The results clearly show the short-term effect of the recent hard winters, yet also provides powerful testimony to the effects of other, longer-term changes in the Scottish countryside. We simply wouldn't be able to understand the magnitude and scale of these changes without the many hours of surveying carried out by committed volunteers."

Louise Smith of RSPB Scotland said: “The Breeding Bird Survey is an important piece of the jigsaw when building a clear picture of Scotland’s bird populations. Whilst some species seem to be exceeding our expectations, others it appears are giving real cause for concern. The sharp decline of wading birds, in particular the Curlew, is something that through our work with farmers, landowners, agricultural bodies and the Scottish Government we hope to reverse before this distinctive bird vanishes from our countryside completely.”

Notes for Editors

  1. For a PDF of the full report visit www.bto.org/bbs/results/BBSreport10
  2. The Breeding Bird Survey is run by the British Trust for Ornithology (BTO) and is jointly funded by BTO, the Joint Nature Conservation Committee (JNCC) (on behalf of the statutory nature conservation agencies: Council for Nature Conservation and the Countryside, the Countryside Council for Wales, Natural England and Scottish Natural Heritage), and the Royal Society for the Protection of Birds (RSPB).
  3. The BTO/JNCC/RSPB Breeding Bird Survey (BBS) is a national project aimed at keeping track of changes in the breeding populations of widespread bird species in the UK. The BBS involves over 2,500 participants who now survey more than 3,200 sites across the UK, enabling us to monitor the population changes of over 100 bird species. Knowing to what extent bird populations are increasing or decreasing is fundamental to bird conservation.
  4. The information provided by the BBS provides a cornerstone for conservation action for birds in the UK. This survey forms an integral part of the Government’s Quality of Life indicators.
  5. This important survey is carried out by volunteer birdwatchers throughout the UK, who receive no financial reward or expenses for their efforts. We are indebted to them for their tremendous support.
  6. The BTO is the UK’s leading bird research organisation. Over thirty thousand birdwatchers contribute to the BTO’s surveys. They collect information that forms the basis of conservation action in the UK. The BTO maintains a staff of 100 at its offices in Norfolk, Stirling and Bangor, who analyse and publicise the results of project work. The BTO’s investigations are funded by government, industry and conservation organisations.

Contact information

Kate Risely
(Breeding Bird Survey Organiser)
Office: 01842 750050
Email: bbs [at] bto.org

Mandy Cook
(BTO Scotland Development Coordinator)
Office: 01786 466 562
Email: mandy.cook [at] bto.org

Paul Stancliffe
(BTO Press Officer)
Office: 01842 750050 (9am-5.30pm)
Mobile: 07585 440910 (anytime)
Email: press [at] bto.org

Louise Smith
(National Media & Communications Officer)
(RSPB Scotland)
Office: 0131 3174136
Mobile: 07540 121457

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Please contact images [at] bto.org quoting reference 2011-29

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