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 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.
From collection: Marine Litter Vital Graphics