Keep an eye out for colour-dyed Manx Shearwaters

01 Jul 2010 | No. 2010-07-35

On Friday July 10, the British Trust for Ornithology (BTO) colour-dyed 31 Manx Shearwaters at the Copeland Bird Observatory off the coast of Northern Ireland. The BTO are encouraging anyone who sees these birds to record and report their observations.

  The foraging areas and migration flyways of
Manx Shearwaters from two UK colonies are
being investigated.

Understanding the movements of migrating seabirds is important for delivering effective conservation, but such information is still lacking or poorly understood for many species. The BTO has recently joined forces with Russell Wynn (SeaWatch SW co-ordinator) and Tim Guilford (University of Oxford) in an exciting new project investigating foraging areas and migration flyways of Manx Shearwaters from two UK colonies – Copeland Island, (Copeland Bird Observatory, County Down in Northern Ireland), and Skomer Island (Pembrokeshire), using colour-marking techniques.

To obtain information on foraging areas and migration distribution following breeding, the BTO has recently colour-dyed 31 Manx Shearwaters on July 10 at Copeland. This work is being conducted by Chris Thaxter, Shane Wolsey, and Adrian Blackburn of BTO, Kerry Leonard of Sterna Environmental, and colleagues from the University of Oxford and Copeland Bird Observatory. It is hoped that subsequent observations of colour-dyed birds will build on recent GPS information collected through tagging projects conducted by the University of Oxford, revealing new information of post-breeding movements. If this first phase of the trial is successful, the program may be extended next year to investigate movements of breeding Manx Shearwaters at Copeland in more detail.

Migration flyways may also be similar between birds breeding at different colonies, and at Skomer, Tim and colleagues colour-dyed up to 30 non-breeding Manx Shearwaters in early July. Comparing sightings for both Copeland and Skomer birds during the same year will be useful in developing a wider picture of migration behaviour. Encouragingly, there have already been sightings of colour-dyed Manx Shearwaters from coastal watchpoints in early July.

Recent work has also been conducted by Russell, Tim and colleagues tagging another closely-related species, the Balearic Shearwater, at their Mediterranean breeding grounds to uncover migratory routes - see recent BirdGuides articles here and here. The Balearic Shearwater is a critically endangered species that is being recorded in increasing numbers in southwest UK during non-breeding periods; if the current colour-dyeing project is successful the same methods could potentially be used to further understand movements of this species. Dr Chris Thaxter of the BTO, commented “This colour-dyeing project is building on a wider program of research to improve our understanding of the distribution and migratory behaviour of Manx Shearwaters and Balearic Shearwaters, and the BTO are helping to advance this extensive research.”

We are therefore appealing to anyone that sees one of these colour-dyed birds to report them to SeaWatch SW via the Contact Us page of the project website. Different colour dyes are being used for Skomer and Copeland to avoid confusion; both dyes are harmless to the birds. We request that observers note the following details:

  • Date, time and location
  • General weather/viewing conditions
  • Direction of flight and distance from watchpoint
  • Number of Manx Shearwaters in group
  • Colour and extent of marking (as accurate as possible)
  • Observer name and email/phone number

All reports will be fully acknowledged, and results will be communicated via SeaWatch SW web/email updates. Specific enquiries about the Copeland project should go to Chris Thaxter of BTO (tel: 01842 750050; email: chris.thaxter [at] and enquiries about the Skomer project should be submitted to Russell Wynn via the SeaWatch SW website.

Notes for Editors

  1. 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.
  2. SeaWatch SW is a science- and conservation-based project that aims to improve understanding of the distribution, movements and behaviour of migratory marine animals, e.g. seabirds and cetaceans. A large number of volunteer observers contribute to data collection throughout UK and Ireland. The project is administered by the National Oceanography Centre, Southampton, and is financially supported by Total Foundation, RSPB, BTO, BirdGuides, SAHFOS, Seabird Group, RNBWS and Marine Information Ltd.

Contact information 

Paul Stancliffe (BTO Press Officer)
Office: 01842 750050 (9am to 5.30pm)
Mobile: 07845 900559 (anytime)
Email: press [at]

Images are available for use alongside this News Release
Please contact images [at] quoting reference 2010-07-35

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

Related content