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The present paper provides information on the stranding of cetaceans in İzmir Bay, Aegean Sea, between 1992 and 2004. The data were collected opportunistically during sightings and stranding data collection for Monk Seals. A total of 12 cetaceans, namely Bottle-nosed Dolphin, Tursiops truncatus (n=6), Common Dolphin, Delphinus delphis (n=3), – reported for the first time – and Striped Dolphin, Stenella coeruleoalba, (n=3) were found to be stranded. © 2004 Taylor & Francis Group, LLC.

After a small amount of oil had leaked into the southern North Sea as a results of the collision between the oil tanker Vicky and the sunken car carrier Tricolor on 1 January 2003, 249 oiled birds (98% Guillemot Uria aalge and Razorbill Alca torda) were received at the Bird Rehabilitation Centre at Ostend, Belgium. Following a second larger oil spill during the salvage works of the Tricolor a few weeks later, in total 9,177 birds stranded at the Belgian coast during the period 23 January to 15 February. This time, virtually all birds were heavily oiled and more than half of the birds were still alive on arrival in Ostend. More than 90% of the victims were Guillemot and Razorbill; other species that accounted for more than 1% of the stranded birds were Great Crested Grebe Podiceps cristatus and Common Scoter Melanitta nigra. The birds stranded in three waves. A first peak in numbers (> 1,000 victims per day) occurred at 26 January and consisted of high proportions of Guillemots that managed to reach the coast alive despite unfavourable wind conditions. In the following weeks, the daily numbers of stranded birds were closely related to the prevailing wind conditions. The second and third peak in the number of strandings coincided with two periods of strong onshore winds. Changes in the species composition and the location where the birds were found are thought to reflect the movements of the oil slick perpendicular and parallel to the coastline, respectively. The proportion of Razorbills among the auks found during the incident greatly differed from that at sea and the proportion of dead birds was much higher among Razorbills than Guillemots. These differences can not be explained from differences in wintering areas. It is suggested that the third peak in strandings was at least partly related to a wreck among auks that was unrelated to the oil polluation.

In der Dissertation werden verschiedene Methoden vorgestellt, die die Strukturantwort des Schiffes bei weicher Grundberührung, auch Strandung genannt, in Tidegewässern berechnen. Die kritischen Kombinationen aus Strandungsposition, Tideeffekten und Beladung sowie globale und lokale Schäden u.a. unter Verwendung der Finiten-Elemente Methode werden berechnet. Der Einfluss der Querkraft auf das Grenztraglastmoment wird über neue Momenten-Querkraft-Interaktionskurven bestimmt. Die Berechnung eines wirklichen Strandungsunfalls mit den vorgeschlagenen Methoden zeigt sehr gute Übereinstimmungen., The thesis reports on different methods to assess the consequences of soft grounding accidents, called stranding, to the ship structure in tidal waters. The critical combinations of stranding position, tidal range and load case are calculated as well as the complete global and local damage process with the finite element method. Moment-shear force interaction curves based on the combined loading conditions are given to evaluate the influence of the shear force on the ultimate hull girder strength. The proposed methods are applicable to any ship type for calculating real stranding accidents. Very good conformance with one known accident is achieved.