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Harmful effects

Marine Debris Header
Did you know?
Commercial Ship
Plastics make up about 60 percent of marine rubbish, and can last for 10-20 years on the ocean floor.

Marine debris can have a range of environmental impacts on our marine wildlife and their environment. Marine debris is hazardous for all marine creatures, particularly to those animals listed as threatened under the Environment Protection and Biodiversity Conservation Act 1999.

Loggerhead with hook
 Loggerhead with
fishing hook

Smaller pieces of rubbish, like cigarette butts and fishing hooks can be confused with prey and swallowed by marine wildlife causing internal blockages, often resulting in starvation and other complications. Sharp objects are also a major concern, as they may be swallowed, causing damage to an animal's mouth, digestive tract and stomach.

It is estimated that some 1 million seabirds and 100,000 other marine animals including turtles, whales and dugong and countless fish are killed as a result of plastic litter every year.

It is estimated that between 50-80 million plastic shopping bags enter the Australian environment as litter every year. If 80 million plastic bags were made into a single plastic sheet, it would cover 16 square kilometres! Each side of the plastic sheet would be 4kilometres long and it would be big enough to cover the Melbourne Central Business District.

Although much marine debris ends up on beaches many items will never float ashore. Many, particularly nets, become entangled underwater on rocky outcrops and reefs, and some may be washed back out to sea during high winds and tides.

Shark caught in net
Shark caught in
fishing net

Many protected species such as turtles, whales, dugongs and sawfish have been recorded entangled in fishing debris along the Australian coastline.

Marine debris can also become a navigational hazard. Debris, especially torn fishing nets, has resulted in the entanglement of rudders and propellers of marine vessels and there have been reports of smaller items clogging cooling water intakes and causing engine failure. Debris is also a hazard to beachgoers, especially children playing on beaches who can may themselves on broken glass.