Big garden beak watch

01 Dec 2010 | No. 2010-12-62

We know surprisingly little about bill deformities in birds and their underlying causes, perhaps because they remain relatively uncommon. As a first step to increasing our understanding, the British Trust for Ornithology (BTO) has just launched a new survey. Called Big Garden Beak Watch, it aims to find out more about the species involved and how individual birds cope with different types of deformity.

Householders that see a bird with a
deformed beak are being asked to report
their observation to the BTO.

With its network of 15,000 Garden BirdWatchers, the BTO is well-placed to learn about the lives of garden birds and, over recent months, its participants have highlighted a number of birds with distinct beak abnormalities. Deformities can include crossed beaks, decurved upper beaks and elongated beaks.

In order to find out how common different beak deformities are and to explore which species are most frequently affected, the BTO is launching Big Garden Beak Watch. Householders that see a bird with a deformed beak are being asked to report their observation to the BTO. Observations will ideally be made through an online survey form (, which asks simple questions about the bird and its behaviour, but those without access to the Internet can send their observations to the BTO at Big Garden Beak Watch, BTO, The Nunnery, Thetford, Norfolk, IP24 2PU.

Dr Tim Harrison, BTO Garden Ecology Team, commented: “Beak abnormalities have been reported in over 60 species of birds worldwide, from sparrows to pigeons, warblers to gulls. Successful adaptation to deformities appears to be more likely if the abnormality occurs gradually rather than as a result of sudden injury. However, there is much that we do not know and we hope that the public can help.”

He added “We anticipate that observers will report back some fascinating behaviour. Some individuals with bill deformities have been observed tilting their head to one side in order to feed, while others even seem to benefit from their ailment; for example, one deformed Great Tit was quicker at extracting nuts from their shells than a normal-billed individual!”

Householders who wish to participate in Big Garden Beak Watch or would like more information should visit from 29 December 2010, email gbw [at], or write to Big Garden Beak Watch, BTO, The Nunnery, Thetford, Norfolk, IP24 2PU.

For journalists who wish to find out more information before 29 December 2010, please visit

Notes for Editors

  1. Birds with beak deformities. Images of birds with bill deformities are available for use alongside this press release, including the image shown overleaf.
  2. Big Garden Beak Watch commences on 29 December 2010 with no set end-date. Results will be published on the BTO’s website in April 2011.
  3. 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 and Stirling, who analyse and publicise the results of project work. The BTO’s investigations are funded by government, industry and conservation organisations.

Contact information 

Tim Harrison (BTO Garden BirdWatch Development Officer) – 22 & 23 December
Office: 01842 750050 (9am to 5.30pm)
Email: gbw [at]

Mike Toms (BTO Head of Garden Ecology) – 29, 30 & 31 December
Office: 01842 768209 (office hours)
Email: gbw [at]

Paul Stancliffe (BTO Press Officer) – 24 December
Mobile: 07585 440910 (anytime)
Email: press [at]

Images are available for use alongside this News Release
Please contact images [at] quoting reference 2010-12-62

The BTO has an ISDN line available for radio interviews
Please contact us to book an interview
Office: 01842 750050  

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