Marine Litter Vital Graphics

Marine Litter

Vital Graphics

buoyant and floats on the surface; however the ocean

floor may be its final resting place (Goldberg, 1997). Large

items, including discarded or lost fishing gear, quickly

sink to the sea floor. These items can smother benthic

organisms, crush vegetation and coral and turn sediments

anoxic (Kuhn et al., 2015). Examples include fishing line

wrapped around coral colonies causing death, plastic

bags directly smothering organisms or reducing light

penetration, and large items dragged along the sea floor

causing physical damage (Kuhn et al., 2015; Yoshikawa

and Asoh, 2004).

Floating away

The artificial habitats provided by floating marine debris

can support a diverse marine ecosystem. Kiessling

et al. (2015) report that globally, 387 taxa, including

microorganisms, seaweed, and invertebrates, have been

found on floating litter. They found that, in most of the

world’s oceans, stalked barnacles (a prominent fouling

species) were the most common organisms colonizing

floating litter. It is not only large mats of litter that provide

a home for marine organisms; one species of water

strider has found that microplastic particles provide

an ideal site to lay eggs. Goldstein et al. (2012) suggest

that the increase in numbers of the pelagic water strider

Halobates sericues

in the region of the North Pacific

Subtropical Gyre is a direct result of the increase in hard

substrate provided by microplastic.

Floating litter provides an additional dispersal mechanism

for natural floating materials such as kelp mats, pumice

and wood. Although these rafts of rubbish, moved by

the same wind and currents as natural material, do not

provide new dispersal pathways, the persistence and

wide distribution of large amounts of plastic in the oceans

provides greater opportunity for dispersal (Lewis et al.,

2005). It has been suggested that debris could play a part

in the spread of invasive species. Kiessling et al. (2015)

document numerous examples of potential invaders

found on marine litter beyond their natural dispersal

range. They conclude that changes to the temporal and

spatial availability of rafts, caused by the growing quantity

of marine litter, probably facilitate the establishment of

species in new regions.

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