Beached Bird Surveys, September – November 1990

Since Sula’s last issue was published, some more counts of beached birds from last summer were received. Mass mortality of Eider was recorded in the Wadden Sea area (PW, KvD), but because so few surveys were conducted in this season it is impossible to estimate total mortality. It is not quite understood why the Eider, in which in recent years also the breeding success has been very poor, dies in such numbers! Extreme cases of primary feather abrasion were reported and it is possible that this mortality is mainly caused by parasites or poisoning (KvD, MFL). Few beached bird surveys were carried out in September and October. September surveys were dominated by stranded Fulmars and Herring Gulls. None of the reported corpses of these two species were oiled. The first few Kittiwakes and Guillemots were found dead and following the severe September storms and the remarkable influx of Storm Petrels along the coast, corpses of Storm Petrel (3034, Wbr), Leach’s Petrel (2023, JvD) and Manx Shearwater (5078, GOK) were picked up. September densities were rather low overall, with exceptions being 5.2/km on Schiermonnikoog (GOK) and 3.7/km near Sexbierum (DS; in both cases mainly Eider). Also October produced low densities, with 2.4/km on Texel being the highest on record (CJC), with again several Fulmars, Eiders and Herring Gulls. Most other species (wildfowl, waders, Kittiwake, terns, and auks) were recorded incidentally. Passerines were found wrecked in relatively small numbers regarding the enormous numbers seen migrating and found disorientated on board vessels in fog conditions this month.