Working Group on Seabird Ecology (WGSE). ICES CM 2004/C:05 ...

Contents
1 Introduction................................................................................................................................................................ 5
1.1 Participation .................................................................................................................................................... 5
1.2 Terms of Reference......................................................................................................................................... 5
1.3 Overview by the Chair .................................................................................................................................... 5
1.4 Note on bird names ......................................................................................................................................... 6
1.5 Acknowledgements......................................................................................................................................... 6
2 Factors influencing trends in abundance of seabirds in the Baltic Sea....................................................................... 6
2.1 Introduction..................................................................................................................................................... 6
2.2 Factors known or assumed to be responsible for the trends observed............................................................. 6
2.2.1 Climate ............................................................................................................................................... 6
2.2.2 Bycatch in fishing gear ........................................................................................................................ 6
2.2.3 Fishery discards and offal.................................................................................................................... 7
2.2.4 Oil pollution......................................................................................................................................... 7
2.2.5 Predation by native and introduced predators...................................................................................... 7
2.2.6 Coastal zone development ................................................................................................................... 8
2.2.7 Marine wind farms............................................................................................................................... 8
2.2.8 Sand and gravel extraction................................................................................................................... 8
2.2.9 Hunting ............................................................................................................................................... 8
2.2.10 Other factors ........................................................................................................................................ 8
2.3 Discussion....................................................................................................................................................... 9
2.4 References....................................................................................................................................................... 9
3 Progress in measuring impacts of at-sea wind farms on seabirds............................................................................. 10
3.1 Introduction................................................................................................................................................... 10
3.2 Recent advances in measuring impacts of existing wind farms on seabird................................................... 10
3.3 Recent progress in understanding bird migration at sea................................................................................ 10
3.4 Recent progress in site-selection procedures ................................................................................................ 11
3.5 Progress and future plans of monitoring possible impacts of wind farms on seabirds.................................. 11
3.6 References..................................................................................................................................................... 12
4 Climatic effects on seabird population performance................................................................................................ 14
4.1 Introduction................................................................................................................................................... 14
4.2 Relations between seabird population performance and climate .................................................................. 15
4.2.1 Phenology .......................................................................................................................................... 15
4.2.2 Breeding success................................................................................................................................ 16
4.2.3 Survival ............................................................................................................................................. 16
4.3 Scale issues ................................................................................................................................................... 16
4.4 Conclusions................................................................................................................................................... 16
4.5 Summary....................................................................................................................................................... 17
4.6 References..................................................................................................................................................... 17
5 A comparison of seabird communities and prey consumption in the east and west north atlantic........................... 18
5.1 Introduction................................................................................................................................................... 18
5.1.1 Population estimates .......................................................................................................................... 18
5.2 Results........................................................................................................................................................... 20
5.2.1 Breeding populations (adapted from ICES 2003).............................................................................. 20
5.2.2 Seasonal changes in numbers and biomass of seabirds in ICES and NAFO areas ............................ 22
5.2.3 Consumption estimates...................................................................................................................... 24
5.2.4 Comparison to earlier models............................................................................................................ 25
5.3 References..................................................................................................................................................... 26
6 Consumption of prey by seabirds in the North Sea as input for the Study <strong>Group</strong> on Multispecies Assessments in
the North Sea (SGMSNS) ........................................................................................................................................ 29
7 Ecological quality objectives.................................................................................................................................... 29
7.1 Introduction................................................................................................................................................... 29
7.2 Proportion of oiled common guillemots among those found dead or dying on beaches............................... 30
7.3 Mercury concentrations in seabird eggs (and feathers)................................................................................. 31
7.4 Organochlorine concentrations in seabird eggs ............................................................................................ 31
7.5 Plastic particles in stomachs of seabirds ....................................................................................................... 32
7.6 Local sandeel availability to black-legged kittiwakes................................................................................... 33
7.6.1 Objective............................................................................................................................................ 33
7.6.2 Can black-legged kittiwake breeding success be monitored accurately?........................................... 33
ICES WGSE Report 2004 3