Distribution and abundance of debris on the continental shelf of the north-western Mediterranean Sea

The distribution and abundance of marine debris were investigated on the continental shelf of the northwestern Mediterranean Sea during three oceanographic cruises undertaken between November 1993 and July 1994. The debris included pieces of plastic, plastic and glass bottles, metallic objects, glass and fishing gear. The results showed peak abundance in areas off metropolitan areas. Concentrations of more than 200 pieces of debris ha−1 were found around Marseille. In most of the stations sampled, plastic bags accounted for more than 90% of total debris. In the Gulf of Lion, most of the debris was found in submarine canyons to a depth of 700 m. The results are interpreted in terms of hydrological conditions.