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It’s difficult to accurately say how much garbage there is in the ocean, but what we do know is that huge amounts of all sorts of waste finish up there. It’s been estimated that 14 billion tons of rubbish ends up in our beautiful oceans every year. And a lot of that rubbish is now swirling around in the Great Pacific Garbage Patch.
Plastics make up the most of this enormous trash island, mainly because other types of waste decay more quickly. ‘The issue is that it’s the plastics that remain and are visible. Food, paper, cans and cigarette butts are not so visible as they degrade in a shorter time period,’ Dr Trevor Thornton, from Deakin’s School of Life and Environmental Sciences, explains.
Many of us in Australia make the decision to recycle and say no to plastics, such as bags, straws, toothpicks, cotton ear tips, and take-away knives and fork. But for many developing countries, littering is the norm, and recycling just isn’t a priority. So what are we doing about all the waste in the ocean? Is the Great Pacific Garbage Patch here to stay?
The Great Pacific Garbage Patch is caused by seawater currents at the surface, pushed along by prevailing oceanic winds. The result is large circular movements of water or gyres that spiral around a central point. What’s different is that these gyres are full of our waste.
‘Litter floating on the surface can be carried along in the direction of the prevailing water movement, eventually spinning towards the centre of the gyre where it piles up with other floating debris to form vast semi-submerged rafts of floating islands,’ Associate Professor Julie Mondon, from Deakin’s School of Life and Environmental Sciences, describes.
The Great Pacific Garbage Patch is made up of two of these gyres in the North Pacific Ocean. The smaller one is just south of Japan, and the Great Pacific is between Hawaii and California. They’re not the only patches either – there are six confirmed plastic gyres across the oceans, including one in the Indian Ocean, between South Africa and Western Australia.
Depending on the plastics and debris, some components of the garbage gyre actually provide a habitat for certain marine species. However this minor positive is far outweighed by the huge negative impacts. Many marine animals are suffering and dying because of our waste.
‘Larger ropes and fishing lines cause entanglement and drowning of marine mammals, birds and reptiles. Smaller particles of plastics are ingested, potentially filling or blocking the animals gut leading to starvation,’ Assoc. Prof. Mondon says.
The toxicants adsorbed onto plastics, and the plastics themselves, can also be poisonous to marine animals. Assoc. Prof. Mondon adds: ‘Digested toxicants can leach and transfer these synthetic chemicals up through the food chain and from parents to offspring.’
'Ultimately, it will take a truly international effort to clean up the existing garbage patches and prevent any further transport of debris making its way onto the coasts and out into the ocean currents.'
Associate Professor Julie Mondon,
There are many things we can do to limit the waste that ends up in our oceans. The solutions are relatively simple, according to Dr Thornton. ‘Avoidance of materials is something we should all focus on. Stop using plastics that end up in the litter stream as a priority, but we should also reduce our reliance on plastic for such things as packaging.’
He adds: ‘We also need to stop littering – in many developed countries this has happened – it is largely the developing countries and also countries in the South Pacific that still have a littering problem; and plastics are the main items included in that litter.’
Stopping littering is the first step, but he says education is also needed – ‘more on what not to do, but also alternatives and a push for more use of biodegradable items,’ Dr Thornton advises.
All of us need to be aware of how we use plastic goods, how we dispose of them, and above all how plastics and waste are being dumped, washed and even blown into the sea. Assoc. Prof. Mondon sums it up: ‘Ultimately, it will take a truly international effort to clean up the existing garbage patches and prevent any further transport of debris making its way onto the coasts and out into the ocean currents.’
The main issue still stands though – many of the items ending up in the oceans can’t be recycled, and sending out garbage collections ships won’t stop us throwing more back in. A future that uses biodegradable plastics would help, but so would changing our bad habits.
Are you passionate about the sustainability of our oceans? Consider studying fisheries and aquaculture at Deakin.
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