CAMPHUYSEN CJ (1995) Sooty and Manx Shearwaters in the southern North Sea: an offshore perspective. LIMOSA 68 (1): 1-9.

So far, the occurrence of Sooty and Manx Shearwaters in the southern North Sea has been described mainly on the basis of observations from coastal sites (seawatching). Recent ship-based surveys (1987-94) have shed more light on distribution, numbers and feeding behaviour of shearwaters in these waters and can be used to interpret seawatching results. Sooty Shearwaters visit the North Sea mainly between July and November. Manx Shearwater is most numerous in the southern North Sea between June and October. Ship-based surveys indicate that both species use an important feeding area off the east coast of Scotland and England, south to the mouth of the river Humber. In these waters, spawning areas of Herring are found and huge concentrations of seabirds and marine mammals have been reported. Manx Shearwaters were most numerous close inshore, whereas Sooty Shearwaters occurred in a c. 80 km wide band along the coast. Both species were comparatively scarce at great distances from the coast. Few shearwaters were found in association with commercial trawlers, indicating that fisheries are only of limited importance for shearwaters in the southern North Sea. It was estimated from ship-based surveys that from August to October about 2300 Sooty Shearwaters and 1700 Manx Shearwaters occurred in the southern North Sea. Of these extrapolated numbers, 96% and 98% respectively occurred in a small area off the English east coast. The shearwaters seen from coastal sites in The Netherlands are likely to be birds that abandoned the traditional feeding grounds off East England because of prolonged periods of hard weather, moving southeast in search of alternative feeding areas. Seawatching data and anecdotal, historical reports on presence of shearwaters in the North Sea indicate that substantial variation between years occurs with respect to number of birds entering the North Sea. Sooty Shearwater Puffinus griseus Manx Shearwater Puffinus puffinus

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