Tagging unlocks the secret lives of St Ives’ gulls

No.:  2016-30
July 2016

A newly-published paper in Ringing & Migration, the journal of the British Trust for Ornithology (BTO) Ringing Scheme, explains how state-of-the art GPS tags have unlocked the secrets of four Herring Gulls nesting on the rooftops of St Ives, Cornwall, a seaside resort where gulls can be unpopular with residents and visitors alike during the summer months. Two male and two female birds were captured and fitted with GPS backpack tags while they incubated their eggs on a cinema, supermarket and local restaurants. This allowed their movements to be tracked throughout the summer of 2014. 

Herring Gull by John Harding/BTO

As many urban-dwellers know, large gulls have increasingly been nesting and feeding in towns and cities in recent decades. This has brought them into conflict with many people, who dislike the noise and mess associated with gulls, not to mention the threat of having their ice creams and chips stolen. The results from the GPS tags revealed huge variation in the movements and feeding habits of the four individuals tracked, but showed that none of them spent much time in the streets of St Ives, suggesting they did not habitually feed on food waste or snatch ice creams. Instead, two birds were true “seagulls”, spending much of their time more than 30km out to sea, whereas the remaining two rarely went more than 1km from the shore. All birds visited farms close to St Ives, where their movements indicated that they apparently followed a plough or a harvester.

Peter Rock, lead author of the study said, “We have two populations of the large gulls in UK – the rural and the urban. We know a great deal about rural gulls, but because they have been under-studied, our knowledge of urban gulls is nowhere near as good as it should be. In view of the bad press surrounding urban gulls, it’s a situation that must change and this small study points the way.”

Dr Viola Ross-Smith, BTO, said, “This study demonstrates that gulls behave as individuals and there can be no one size fits all approach when it comes to managing their populations. It is vital that any decisions about gull conservation and management are based on the best scientific evidence available if they are to succeed.”

Although gulls appear to be thriving in urban areas, many species are in decline nationally, including the Herring Gull, which is on the Birds of Conservation Concern Red List. Future work will now build on this study, helping us to understand the success of urban gulls, the conservation needs of gulls breeding in rural colonies, and to come up with sustainable management strategies for co-existing with gulls as feathered friends, rather than fiends.

Notes for Editors

  1. This research has been published as Rock, P., Camphuysen, C.J., Shamoun-Baranes, J., Ross-Smith, V.H. & Vaughan, I.P. (2016) Results from the first GPS tracking of roof-nesting Herring Gulls Larus argentatus in the UK. Ringing & Migration 31, 1-16. http://dx.doi.org/10.1080/03078698.2016.1197698
     
  2. Ringing & Migration is the journal of the BTO Ringing Scheme (http://www.bto.org/ringing/). Published since 1975, the journal welcomes papers on all aspects of bird ringing and migration studies.
     
  3. The BTO is the UK's leading bird research charity. A growing membership and up to 60,000 volunteer birdwatchers contribute to the BTO's surveys, collecting information that underpins conservation action in the UK. The BTO maintains a staff of 100 at its offices in Thetford, Stirling, Bangor (Wales) and Bangor (Northern Ireland), who analyse and publicise the results of surveys and projects. The BTO's work is funded by BTO supporters, government, trusts, industry and conservation organisations. www.bto.org.
     
  4. The Birds of Conservation Concern report assesses bird species on their conservation importance. They are grouped into three lists: Red, Amber and Green, with Red being birds of the highest conservation concern and priority. UK Red List birds are species that are considered globally threatened, or have seen severe declines in breeding populations and breeding ranges in the past 25 years. For more information, visit: www.bto.org/science/monitoring/psob.
     
  5. UvA-BiTS is a state-of-the-art bird tracking system developed by a team from the University of Amsterdam. The system involves a solar-powered GPS tag with rechargeable batteries and two-way data connection to a ground station, as well as automated data processing and visualisation. The data from the UvA-BiTS project is being used by researchers from a number of organisations to study migration, navigation and more. For more information, visit: www.uva-bits.nl.

Contact Details

Dr Viola Ross-Smith
(BTO Science Communications Manager)

Office: 01842 750050 (9am to 5.30pm)
Mobile: 07776 238622
Email: viola.ross-smith [at] bto.org

Peter Rock
Pete.rock [at] blueyonder.co.uk
Mobile: 07811 178398

Paul Stancliffe
(BTO Media Manager)

Office: 01842 750050 (9am to 5.30pm)
Mobile: 07585 440910 (anytime)
Email: press [at] bto.org

Images are available for use alongside this News Release. Please contact images [at] bto.org quoting reference 2016-July-30

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