Page 452 - Environment: The Science Behind the Stories

(a) Plastics entangling wildlife (b) Tiny bits of debris from ocean gyres

(c) Organisms ingesting plastics (d) Preventing oceanic plastic pollution
Figure 16.16 Plastics affect oceanic life. Like thousands of marine mammals every year, this grey seal
(a) became entangled in a discarded fishing net. Small pieces of plastic like this sample from the “Great
Pacific Garbage Patch” are also dangerous to organisms (b). Plastics are often mistaken for food items
and ingested by wildlife, such as by this dead albatross (c). Prevention is the best approach for addressing
oceanic plastic pollution. Here, booms capture trash in the Los Angeles River (d) to prevent it from entering
the Pacific Ocean.

low-temperature, low-light conditions are not favorable for ants (POPs; p. 402) such as DDT and PCBs, thereby increasing
degradation. In the North Sea, for example, underwater surveys the toxicity of the plastic to any organism that ingests it.
have found over 100 pieces of plastic per km on the ocean floor. Floating pieces of plastic also serve as “rafts” and trans-
2
Floating plastics are particularly harmful to marine life. port species over long distances they could not travel on their
Organisms mistake the small pieces of plastic for plankton or own. Seaweeds, sessile (nonswimming) invertebrates, and other CHAPTER 16 • M AR in E A nd Co A s TA l s ys TEM s A nd R E sou R CE s
fish eggs, ingest them, and suffer injury or death (Figure 16.16c). creatures have become invasive species when carried to new
A 2010 study found that the average plankton-eating fish in habitats on floating plastic. For example, two species of bryozo-
the Great Pacific Garbage Patch had 2.1 pieces of plastic in ans (a predatory, sessile invertebrate that forms polyps on sea-
its digestive system. Fish are not the only organisms affected. weed and stones) from the Caribbean are reaching the Florida
Seabird chicks are killed when parents unknowingly feed them coast on floating plastics and are impacting native species.
pieces of plastic when regurgitating food. One study attributed Because plastics take 500–1000 years to degrade at sea and
40% of premature deaths of Albatross chicks in the Pacific there is no viable way to collect the small bits of plastics that litter
islands of Midway to this cause. Some 267 species are affected the oceans, preventing their entry into the oceans is key to rem-
by marine plastic debris, leading to an estimated 100,000 edying oceanic plastic pollution (Figure 16.16d). In 2006, the U.S.
marine mammals and 1 million seabird deaths each year. Congress responded to ocean pollution by passing the Marine
Plastics can have toxic effects on organisms. Plastics con- Debris Research, Prevention, and Reduction Act, aiding efforts
tain harmful substances, such as bisphenol A and phthalates to keep plastics out of marine waters. These and other efforts are
(Chapter 14), which leach into ocean water or the digestive tracts ecologically wise but also convey significant economic benefits.
of animals (if the plastic is ingested). Pieces of plastic in the In Asia alone, the costs of plastic pollution on fisheries, tourism,
ocean can also “grab” and concentrate persistent organic pollut- and other industries is an estimated $1 billion a year. 451

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