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MARINE POLLUTION:

Marine litter (debris) = all objects that do not naturally occur in the marine and coastal environment

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MARINE POLLUTION:

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    2. Marine litter (debris) = all objects that do not naturally occur in the marine and coastal environment water surface, water column, seabed, shore but are nevertheless found there.

    3. Further defined Marine litter is any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the the marine and coastal environment.

    4. 70% of marine litter sinks - found on the seabed in both shallow coastal waters and the deep sea While items such as needles from medical waste, tin cans and glass bottles pose obvious dangers, it is plastic which poses the biggest threat to wildlife and people. Almost 90% of floating marine debris is plastic The majority of litter (more than 50%) found at sea or on beaches is made of plastic [72% in Hawaii McDermid and McMullen (2004)]

    6. A survey of floating plastic marine debris in the Southern, Atlantic and Arctic Oceans noted such debris in all regions (0-10 items/km2) Even in the Southern Ocean (Antarctica) debris was found (3 items/km2) As study from ten years earlier encountered similar rates of debris. This illustrates the widespread nature of marine debris, even in pristine environments. The researchers also noted that marine debris could be a probable vector of invasive species (rafting). [Barnes and Milner (2005)]

    7. The Algalita Marine Research Foundation (US), was conducting a survey across the North Pacific Central Gyre in 2002 Between Hawaii and California they reported an immense field of plastic debris almost the size of Central Europe They reported a 6:1 weight ratio of floating and suspended plastic to zooplankton (i.e. floating plastic weight = 6x zooplankton weight)

    8. Impacts of Marine Debris on Marine Life Entanglement Injury or death Reduced circulation Impairment of abilities Ingestion Choking Blocking digestive tract starvation False satiation - starvation Stomach ulceration Leaching of toxic materials

    9. Entanglement Entanglement/entrapment occurs when an animal becomes encircled or ensnared by an object most common = discarded (ghost) fishing nets Over 143 marine species, including all sea turtle species, have been reported in entanglement accidents Over 100,000 marine mammals and turtles alone die due to marine debris entanglement Its been proposed that entanglement was a major contributor to the decline of the Alaskan Northern Fur Seal - 50,000 deaths annually An estimated 1 million seabirds die every year [Laist (1987, 1997)]

    17. Ingestion Ingestion occurs when an animal swallows a litter item, sometimes accidentally, more frequently because it looks like a food source Young, inexperienced animals may be particularly vulnerable Over 177 marine species have been reported to accidentally eat plastic

    18. Ingestion by seabirds On the Aleutian Islands (Alaska) 37 species of bird were reported to have ingested plastics the rate of this ingestion has increased. Many of these were planktivorous birds with sieve-like beak adaptations Some animals had stomachs packed with particles Adult birds can feed this particles to chicks when they regurgitate food Carnivorous birds (e.g. skuas) ingest plastic their prey has eaten [Robarts et al. (1995)]

    19. Beach Litter 2000 - study of marine litter along 26 beaches around the Sea of Japan in both Japan and Russia Average number of pieces: Japan = 341/100m2 Russia = 20.7/100m2 Plastic accounted for between 40-80% of all items in terms of weight and number of pieces [Kusui and Noda (2003)].

    20. Sept. 2001 Feb. 2003 - study of small plastic debris on 9 coastal areas of Hawaiian Archipelago [McDermid and McMullen (2004)] Greatest quantities were found on 3 of the most remote beaches 72% of debris was plastic by weight The greater quantities at remote beaches may be due to regular clean-ups at more populated sites Beach Litter

    21. Large quantities of marine debris were found in the habitat of the endangered Hawaiian monk seal [Boland and Donahue (2003)] Plots of reef were surveyed and cleaned of debris and re-examined one and two years later = 16-165 pieces of debris/km2 Up to 141 pieces of debris /km2 added every year 84% of the debris was discarded fishing gear. Beach Litter

    22. Ingestion at the bottom of the food chain Microscopic plastic fragments and fibers are widespread in the pelagic zone Fragments appear to result from degradation of larger objects Biodegradable plastics are composites with materials such as starch that do degrade - but leave behind non-degradable plastic fragments Some cleaning agents also contain abrasive plastic fragments

    23. Surveys of coastal plankton samples found microscopic plastic fragments [Thompson et al. (2004)] Plastic fragments were recorded in the 1960s -but levels of plastic increased over time Laboratory experiments proved that microscopic plastic particles were being ingested by amphipods, lugworms and barnacles [Thompson et al. (2004)] These ingested plastics may leach toxic materials but research so far is inconclusive Ingestion at the bottom of the food chain

    26. Economic impact Estimated $250 million of revenue annually is lost due to ghost fishing removing catchable fish , crabs etc. Survey in Newport, Oregon 58% of fishermen annually spend up to $2,725 per vessel due to plastic debris damage Estimated $50 million annual in vessel insurance claims from engine damage due to plastics

    27. References Barnes, D.K.A. and Milner, P. 2005. Drifting plastic and its consequences for sessile organism dispersal in the Atlantic Ocean. Marine Biology 146: 815-82 Boland, R.C. and Donahue, M.J. 2003. Marine debris accumulation in the nearshore habitat of the endangered Hawaiian monk seal, Monachus schauinslandi 1999-2001. Marine Pollution Bulletin 46: 1385-1394. Kusui, T. and Noda, M. 2003. International survey on the distribution of stranded and buried litter on beaches along the sea of Japan. Marine Pollution Bulletin 47: 175-179. Laist, D.W. 1987. Overview of the biological effects of lost and discarded plastic debris in the marine environment. Marine Pollution Bulletin 18: 319-326. Laist, D.W. 1997. Impacts of Marine Debris: Entanglement of marine life in marine debris including a comprehensive list of species with entanglement and ingestion records. In: Marine Debris: Sources, Impacts and Solutions (Ed. by J. Coe and D.B. Rogers). Springer Series on Environmental Management. Springer-Verlag, New York McDermid, K.J. and McMullen, T.L. 2004. Quantitative analysis of small-plastic debris on beaches in the Hawaiian archipelago. Marine Pollution Bulletin 48: 790-794 Moore, C.J., Moore,S.L., Leecaster M.K. and Weisberg, S.B. 2001. A comparison of plastic and plankton inthe North Pacific central gyre. Marine Pollution Bulletin 42. Robarts, M.D., Piatt, J.F. and Wohl, K.D. 1995. Increasing frequency of plastic particles ingested by seabirds in the subarctic north Pacific. Marine Pollution Bulletin 30: 151-157. Thompson, R.C., Olsen, Y., Mitchell, R.P., Davis, A., Rowland, S.J., John, A.W.G., McGonigle, D. and Russell, A.E. 2004. Lost at sea: where is all the plastic?Science 304: 838.

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