New research led by Dr Keith Hamer will assess the extent to which gannets rely on unwanted fish and offal thrown from fishing boats to successfully breed and raise their chicks.

"The North Sea has undergone massive environmental changes over the last twenty years, which has put pressure on nearly all sea bird species," said Dr Hamer, from Leeds' Faculty of Biological Sciences. "Only gannets have consistently bred successfully, partly because they can travel as far as South West Norway to feed, but also because they are able to target food thrown overboard by fishing boats.

"Although discards should be stopped to protect marine biodiversity, research is needed on the impact of a ban, so policy makers can understand the best way to implement it."

Dr Hamer will work with colleagues at the universities of Exeter and Plymouth to fit GPS tracker devices on breeding pairs of gannets from twelve colonies around the UK. The gannets will also be fitted with miniaturised, fast-acting depth recorders, so the researchers can see how deep the birds dive and how they pursue prey underwater - both indicative of the kinds of food they are targeting.

Blood and feather samples from the gannets will be analysed to determine their diet and their nests monitored to check how well they are feeding their chicks.

The data will be plotted against the location of fishing vessels in the North Sea to calculate how many of the birds are relying on discards to breed successfully.

The researchers believe that gannets may have specialised feeding habits, with some individuals relying heavily on discards while others focus on finding sand eels or diving for mackerel and herring. If this theory is correct, a ban would disproportionately affect some breeding pairs, rather than impacting to a lesser degree on the whole colony.

The research builds on more than 10 years of research on gannets by Dr Hamer in addition to work by research team members Stephen Votier in the Marine Biology & Ecology Research Centre, University of Plymouth, and Stuart Bearhop, University of Exeter, published this month in the Journal of Applied Ecology.

"We think gannets have different aptitudes and specialities and for some, that skill might be finding and following fishing boats," said Dr Hamer. "If our hypothesis is wrong and gannets are in fact generalists, with all of them making occasional use of discards, that has a different implication for policy."

There is increasing pressure on the EU to ban discards and legislation is likely in the near future. The three-year, £700,000 research project, funded by the Natural Environment Research Council (NERC), will help inform policy makers of how to ensure new regulations minimise potential impact on the gannets. It could also help the UK government decide where to impose marine protected areas in the North Sea.

"Although the long-term benefits of a ban will be positive, we need to accurately predict short-term impacts as well," says Dr Hamer. "If gannets have specialised to the extent we believe, rather than cut off a crucial food source overnight, a gradual phasing in of the ban would allow them time to retrain to find food elsewhere."

Photos of gannets are available: please contact Campuspr on 0113 258 9880, jokelly@campuspr.co.uk

Further information from:
Jo Kelly, Campuspr Ltd, tel 0113 258 9880, mob 07980 267756, email jokelly@campuspr.co.uk
or
Guy Dixon, University of Leeds press office, tel 0113 343 8299, email g.dixon@leeds.ac.uk

Notes to editors

1. Fishing boats currently discard by-catch: fish or other marine creatures that are too small or are of the wrong species to come under their quota. According to the European Commission's Scientific, Technical and Economic Committee for Fisheries, the level of by-catch discards was, depending on the seas, fisheries and trawls, between 20 and 60 percent of the catch weight for the period 2003-05. Where boats process fish on board, they also discard the unwanted parts of the fish, such as heads or offal.
2. Dr Keith Hamer is a researcher in the University of Leeds' Institute of Integrative and Comparative Biology part of the Faculty of Biological Sciences. He has carried out extensive research on gannet colonies and this current project builds on his earlier findings published last year in the Journal of Animal Ecology.
3. The Faculty of Biological Sciences at the University of Leeds is one of the largest in the UK, with over 150 academic staff and over 400 postdoctoral fellows and postgraduate students. The Faculty is ranked 4th in the UK (Nature Journal, 457 (2009) doi :10.1038/457013a) based on results of the 2008 Research Assessment Exercise (RAE). The RAE feedback noted that "virtually all outputs were assessed as being recognized internationally, with many (60%) being internationally excellent or world-leading" in quality. The Faculty's research grant portfolio totals some £60M and funders include charities, research councils, the European Union and industry. http://www.fbs.leeds.ac.uk/
4. The 2008 Research Assessment Exercise showed the University of Leeds to be the UK's eighth biggest research powerhouse. The University is one of the largest higher education institutions in the UK and a member of the Russell Group of research-intensive universities. The University's vision is to secure a place among the world's top 50 by 2015. http://www.leeds.ac.uk/
5. NERC funds world-class science, in universities and its own research centres, that increases knowledge and understanding of the natural world. It is tackling major environmental issues such as climate change, biodiversity and natural hazards. NERC receives around £400m a year from the government's science budget, which is used to provide independent research and training in the environmental sciences. http://www.nerc.ac.uk/