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Appendix A (TABLE A1). Summary of sample size and spatial distribution of winter observations from the ESAS, IBTS, and CPR databases in the period 1981-1999. ESAS is the European Seabirds At Sea database of strip transect counts of seabirds from ships. Sample units are 20 km strips (0.3 km wide). Data are from 1. October – 31 March. IBTS is the International Bottom Trawl Survey, which is a yearly trawl survey of fish. Sample units are individual trawl hauls. Data are from 6. January – 31.March. CPR is the Continous Plankton Recorder operated by Sir Alisdair Hardy Foundation. Sample units are CPR samples (ca. 18.5 km of towing). Data are from 1. October – 31 March. Average nearest/longest distance is the average longest and average shortest distance between observations within years.