State of the Environment Report 2007
Marine debris is classed as an emerging issue due to its potential to cause significant impacts to marine wildlife, but there is currently inadequate information to report on this as an issue.
'Marine debris' is produced from many different sources, such as litter thrown overboard from boats, litter that gets carried into the marine environment from land or beaches, fishing equipment, and items dumped in other parts of the world that is circulated by currents. Detrimental effects of marine debris include death or injury for wildlife, reduction in aesthetic value and pollution of marine and beach environments. Marine animals often become tangled in discarded fishing gear, plastics and other lost items, which can lead to decreased mobility, infection, amputation and drowning (Department of the Environment and Heritage, 2003). Turtles, whales and seabirds are especially at risk of entanglement. Debris is often mistaken as prey by some marine species and if ingested, it may lead to internal injuries, digestive tract blockages and infections (Jones, 1995). Ocean debris can have negative economic impacts on tourism and fisheries (Wace, 1995), cause injury to beachgoers and divers, and degrade aesthetic values (Whiting, 1998).
Plastics are the most common type of debris found in our oceans and the most destructive to the environment and wildlife (Wace, 1995). Beach debris can take many forms and is usually concentrated around major settlements. Fishing equipment is often the major source of marine debris in more isolated parts of the coastline (Jones, 1995). Throughout Australia, beach surveys have been completed to determine the debris washing up on our shores and to estimate its origin. Nearly 500 kg of marine debris (a total of 11 395 items) was collected from South West beaches between Yallingup and Augusta over a ten-month period in 2005, and included cigarette butts, shopping bags, bait straps, rope and other items (Tangaroa Blue, 2005). However, in WA a very limited number of surveys have been completed and there is a general lack of quantitative data about marine debris.
Garbage from ships is subject to controls under the International Convention for Prevention of Marine Pollution from Ships 1973 (amended in 1978). This convention is enforced through the Protection of the Sea (Prevention of Pollution from Ships) Act 1983 (Commonwealth) in Australia, and prohibits all discarding of plastics overboard. The Australian Seafood Industry Council has developed a voluntary Code of Conduct for a Responsible Seafood Industry. This code aims to minimise waste from fishing industry activities and to ensure all lost fishing gear is recorded and reported.
Environmental management authorities, non-government organisations such as WWF and Planet Ark, and statutory authorities such as the Rottnest Island Authority have completed small surveys or clean-up programs to reduce the amount of debris in the marine environment. Educational programs such as Clean Up Australia Day and Keep Australia Beautiful aim to raise the community's awareness of damage caused by marine debris, especially discarded plastics. Ongoing public campaigns are required because marine debris is still being dumped or discarded and impacting the marine environment.
