Plastic debris can have similar size characteristics to sediment and suspended particulate matter and can be ingested by filter feeding or sediment ingesting organisms. Lugworms, amphipods and barnacles have all been shown to ingest plastic fragments and fibres (Thompson et al., 2004). Even very small organisms at or near the bottom of the food chain, like filter feeding zooplankton, have been observed in the laboratory to take up icroplastics (Cole et al., 2013; Setälä et al., 2014). Zooplankton usually excrete the particles within hours (which is comparable to natural food) but some zooplankton have been found to retain microplastics for up to seven days (Cole et al., 2013). The ingestion of polystyrene particles by zooplankton has been found to significantly decrease their nutritional intake (because they can eat up to 40 per cent less real food) and also their reproductive output (Cole et al., 2015 and Lee et al., 2013). Apart from providing zero energy, a diet of non-nutritional microplastic beads also affects how these organisms deal with food shortages. Usually they instinctively decrease their metabolic rate to save energy when faced with starvation – however this does not occur when the diet contains microplastic beads (Cole et al., 2015).
From collection: Marine Litter Vital Graphics
GRID-Arendal and Maphoto/Riccardo Pravettoni