Marine litter on the Kachelotplate, Lower Saxonian Wadden Sea

Abstract

Beach surveys were carried out from May to November 2007 in monthly intervals to assess the occurrence of marine litter along a 2.5 km stretch of beach on the Kachelotplate, an emerging sandbank island W of Juist, Lower Saxonian Wadden Sea, southern North Sea. A total of 683 items were recorded with an average 60.4 % plastics, 24.5 % wood, 0.9 % glass, 1.6 % metal and 5.3 % other material. Material of natural origin accounted for another 4.3 %. Within the plastics compartment fishery related items were dominant accounting for 36.3 % of total plastics. A source consideration shows that most fishery related items must have originated from the open North Sea while a second major source is the neighbouring island of Borkum. Heavier material such as concretions, stones or bricks most likely must have been originally deposited in shallow waters along the western margin of the Kachelotplate as these must have been transported as bedload. Despite the aesthetically unpleasant nature of debris it fulfils an important role in island build-up, i.e. it acts to trap sand which will remain on the island even after the trapping debris has been removed by flooding.