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Marine Litter
Vital Graphics
IMPACTS
There has been widespread publicity about pollution of the marine environment by
plastic debris and its impact on organisms. Images of the brightly coloured plastic
stomach contents of dead seabirds and countless whales, dolphins and turtles caught
in floating debris or wearing discarded plastic rubbish are routine. But this is not only
about large marine creatures swallowing or getting entangled in rubbish; organisms at
every trophic level, living both on the seabed and in the water column, are also affected.
Ecological impacts of marine plastic
debris and microplastics
The plastic diet
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 microplastics (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).
How plastics enter the food web Sources: Lusher, A., Microplastics in the Marine Environment: Distribution, Interactions and E ects, in Bergmann, M., et al., Marine Anthropogenic Litter, 2015 Less dense microplastics oating on surface water Fouled microplastics sinking Resuspended microplastics Microplastics in beach sediments Microplastics in benthic sediments Pelagic sh Holothurians Zooplankton Mesopelagic sh Demersal sh Bivalves Annelids Crustacans Sea birds Marine mammals How plastics enter the food web Sources: Lusher, A., Microplastics in the Marine Environment: Distribution, Interactions and E ects, in Bergmann, M., et al., Marine Anthropogenic Litter, 2015 Less dense microplastics oating on surface water Fouled microplastics sinking Resuspended microplastics Microplastics in beach sediments Microplastics in benthic sediments Pelagic sh Holothurians Zooplankton Mesopelagic sh Demersal sh Bivalves Annelids Crustacans Sea birds Marine mammals