Marine litter in coastlines, water column and seafloor
The main source of marine litter in the Mediterranean is house- holds. Other major sources are tourist facilities, municipal dumps, ships and pleasure boats.
Most studies of marine litter in the Mediterranean have focused on beaches, floating debris and the seabed (UNEP/MAP 2012). They show that there is more marine litter in bays than in open areas (Galgani et al. 2010), and it is concentrated in shallow coast- al areas rather than deeper waters (Koutsodendris et al. 2008).
A large proportion of marine litter is plastics (UNEP 2009). The impact of large plastic material on the environment has been
Marine litter is “any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment.” It reaches the marine environment through deliberate disposal or unintentional discharge, either at sea or from land by way of rivers, drainage systems and wind. Source: Galgani et al. 2010
widely studied. Effects include entanglement of marine animals in plastic and ingestion of plastic by marine organisms (EEA and UNEP 2006). More attention is now being given to the impact of microplastics from such primary sources as feedstock in the plastics industry and from the breakdown of larger plastic items (GESAMP 2010). While evidence is growing that microplastics can also have negative effects on marine organisms, little scientif- ic investigation has gone into the problem in the Mediterranean or elsewhere (GESAMP 2010). The additional challenge of micro- plastics is their small size, which makes them difficult to remove from the marine environment.
Impacts of marine litter on marine life
Around the world, marine litter kills more than a million seabirds and 100.000 marine mammals and turtles every year (UNEP/MAP 2012). Little information is currently available about the impact of marine litter on Mediterranean wildlife. The most significant effects come from entanglement in or ingestion of marine litter, especially plastics. Sea turtles in the Mediterranean, already seri- ously endangered through habitat loss and by catch, are further threatened by plastic marine litter, which they mistake for their main prey, jellyfish, and swallow (Galgani et al. 2010). The plastic can become lodged in the turtles’ gastrointestinal tracts, result- ing in injury or death.
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STATE OF THE MEDITERRANEAN MARINE AND COASTAL ENVIRONMENT