Marine Litter Vital Graphics

IMPACTS

Number of species with documented records of marine debris ingestion Plasticized animal species - Ingestion

Dugongs and sea cows

Penguins

Marine ducks

Divers

True seals

5

1

3

4

3

(7.7%)

16

(60%)

(27.8%)

Pelicans, gannets and boobies, tropicbirds

(60%)

(21.1%)

40

Invertebrates

Whales

Turtles

Eared seals

6

7

7

16

8

(53.8%)

(100%)

(>0,001%)

(61.5%)

(23.9%)

Toothed whales

(61.5%)

92

84

55

Gulls, skuas, terns and auks

Albatross and other Procellariiformes

Fish

(39.6%)

(0,28%)

(59.6%)

Source: Kühn, S., et al., Deleterious E ects of Litter on Marine Life, in Bergmann, M., et al., Marine Anthropogenic Litter, Springer, 2015

A recent review of microplastics as a vector for chemicals found that the fraction of organic chemicals absorbed by plastics is small compared to other carriers of chemicals in the ocean (these include water, dissolved organic carbon, black carbon and biota; Koelmans et al., 2016 and references therein). The ingestion of microplastics by marine organisms is unlikely to increase their exposure to organic chemicals (Koelmans et al., 2016) but the plastics themselves also release chemicals as they degrade, increasing the overall chemical burden in the ocean. Caught by plastic Entanglement in debris is a more obvious and proven risk to marine life than other impacts of litter, which are still subject to debate. More than 30,000 cases of entanglement (in 243 species) have been reported (Gall and Thompson, 2015). Entanglement can cause a quick or a slow death through drowning, starvation, strangulation or cuts and injury that cause infection (Laist 1997). Much of the damage to organisms is caused by discarded fishing equipment – so-called “ghost fishing”. It is a problem that affects predominantly higher taxa organisms: whales,

turtles, seals, dolphins, dugongs, sharks and large fish. For example, studies examining scarring on whales from the Gulf of Maine indicate that more than 80 per cent of right whales and 50 per cent of humpback whales have experienced entanglement in fishing gear (Knowlton et al., 2011; Robbins and Mattila 2004). In the North West Atlantic, it is estimated that between 1970 and 2009, more than 300 large whales died as a result of entanglement, a significant proportion of them since 1990 (van der Hoop et al., 2012). Northern Australia has a particularly high density of ghost nets (3 tons per km of shore line annually), which pose a threat to endangered marine fauna in the region (Wilcox et al., 2015). It is estimated that more than 8,000 nets collected between 2005 and 2012 could have been responsible for the deaths of more than 14,000 turtles (Wilcox et al., 2015). Ghost fishing entangles species other than those targeted by the fishing gear; it also results in impacts to the targeted species, as the gear continues to trap and catch them without harvesting. Smothering and other damage Much of the marine litter entering the ocean is initially

16

Marine Litter Vital Graphics