title: Estimation of the impact of prevailing weather conditions on the occurrence of oil-contaminated dead birds on the German North Sea coast.
abstract: Chronic oil pollution by illegal oil dumping in the North Sea is difficult to quantify. Beached, oil-contaminated sea birds, however, may be used as an indirect indicator. Reconstructing the drift of oil slicks and sea bird corpses in the southern North Sea for the period 1992-2003 by means of a two-dimensional numerical transport model driven by re-analysed weather data, we show with an example of two common sea bird species that the variability observed within the number of corpses registered during beached bird surveys for the German coast primarily reflects the inter-annual variability of prevailing weather conditions. This should be taken into account when interpreting the data. We propose normalisation of beached bird survey data based on numerical drift simulations to improve the recognition of trends in the level of chronic oil pollution.
authors.affiliation: GKSS Research Centre, Institute for Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht, Germany. alena.chrastansky@gkss.de
authors.forename: Alena
authors.initials: A
authors.lastname: Chrastansky
authors.forename: Ulrich
authors.initials: U
authors.lastname: Callies
authors.forename: David M
authors.initials: DM
authors.lastname: Fleet
mesh_terms: D000818:Animals; D001717:Birds; D003198:Computer Simulation; D004784:Environmental Monitoring / Q000379:methods*; D007219:Industrial Oils / Q000032:analysis / Q000633:toxicity*; D008962:Models, Theoretical; D009659:North Sea; D012767:Ships; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D014887:Weather
chemical_list: D014874:Water Pollutants, Chemical