So where does all this litter come from? There are many sources, but the top four, consistently, are shipping, sewage, fishing and the public. Most of it is preventable, yet levels of debris are increasing every year. Results of Marine Conservation Society surveys indicate that there are, on average, nearly 2,000 items of litter per kilometre on Britain’s beaches. Beach litter is at its highest levels since records began – it has almost doubled in the last 15 years and rose by 6% between 2009 and 2010.
Litter can cause huge problems in the marine environment. Not only is it an eyesore, it can harm marine wildlife and beach visitors too. Beachgoers can be injured by items of marine debris and can become ill from swimming in seawater contaminated with sewage. Shellfish grown in sewage-contaminated water can cause food poisoning to consumers due to a build-up of toxins in their tissues. Marine debris costs local authorities thousands of pounds every year in lost tourism revenue and cleanup costs, and the fishing industry also loses out when their gear becomes fouled by debris and catches are contaminated.
Marine litter kills more than one million sea birds and 100,000 marine mammals every year through ingestion and entanglement. Discarded fishing nets cause problems through ‘ghost fishing’, whereby marine life continues to be caught by nets left behind in the sea. The animals cannot escape and suffer slow deaths whilst trapped. The nets also pose a threat to divers, who can become entangled and trapped in them. A recent story from Honolulu has highlighted the dangers of debris after nine Hawaiian monk seals were rescued from fishing nets and other marine debris, which they had become entangled in. One of the seals was a female pup caught up in an 800lb mess of buoys, fishing nets and clothes baskets.
Marine animals often mistake litter, such a plastic bags and balloons, for food. A recent study has shown that plastic is rapidly becoming a significant "food" item for fishes living in the northern Pacific Ocean. Turtles are particularly susceptible to ingesting plastic, as they frequently mistake floating plastic bags for jellyfish, their main food source. The plastic bags block their stomachs, frequently leading to death through starvation. Seabirds also ingest floating plastic litter, mistaking it for food – over 90% of fulmars found dead around the North Sea have plastic in their stomachs. A study by Scottish scientists has also found that 83% of Langoustines, also known as Scampi or Norway lobster, have indigestible plastic fibres in their stomachs, usually in the form of clogging balls.
In fact, plastics account for more than half of all litter items found on UK beaches and the number of plastic items found annually has increased by 135% since 1994. They are a particular problem because they persist in the marine environment for hundreds if not thousands of years. Every single piece of plastic ever made still exists today. Eventually, plastic breaks down into microscopic particles or ‘snow’, which may be consumed by filter feeding animals such as barnacles. Pollutants can also be attracted to the surface of plastics, posing a previously unrecognised threat to marine animals once ingested. These pollutants may be passed up through the food chain by bioaccumulation to fish, and ultimately to human consumers. The toxic substances released by plastics as they break down can also effect the growth and development of marine animals.
Plastics can accumulate in the marine environment across large areas and there are known trash vortexes in each of the five major ocean gyres. The North Atlantic Garbage patch was originally documented in 1972 and is estimated to be hundreds of kilometers wide, with a density of more than 200,000 items of debris per square kilometer. The existence of the Great Pacific Garbage Patch was predicted by researchers in 1988 and it was subsequently discovered in 1997. It is frequently referred to as an exceptional example of marine pollution but mostly consists of tiny plastic particles that are invisible to the naked eye; more like a "plastic soup". It is consequently difficult to estimate the size of the patch, but it is believed to range somewhere between 700,000 to 15,000,000 square kilometers in size. Researchers say that it is, “growing exponentially and threatening to become one of the greatest ecological disasters of our time”. It is estimated that 80% of the debris originates from land-based sources, and the remaining 20% from shipping. The Indian Ocean Garbage Patch, discovered in 2010, does not appear as one continuous field of debris. Researchers from the 5 Gyres Project are currently investigating this garbage patch, along with those in the South Atlantic and South Pacific.
So what can we do about all this debris in our oceans and on our beaches? At a local level, you can make sure you don’t leave litter behind on the beach and don’t drop it in the street, don’t flush litter down the loo, and don’t take part in events such as balloon releases. You can reduce the amount of waste you produce, reuse items and recycle as much as you can. You could even create your own art installation! You can support charities that work towards acheiving cleaner seas, such as the Marine Conservation Society (MCS), through membership or fundraising. You can get involved with local beach cleans – the MCS uses data from beach cleans around the UK to target litter at source, at local, national and international levels. Their Beachwatch Big Weekend takes place over the third weekend in September each year and coincides with Project AWARE’s ‘International Cleanup Day’. If you dive, you can take part in the Project AWARE ‘Dive Against Debris’ campaign. To tackle the issue of marine debris on a larger scale, the MCS wants:
- Government to formulate coherent marine litter action plans.
- Industry to improve water treatment storage capacity and combined sewer overflows to reduce the discharge of untreated sewage and sewage related litter to rivers and the sea during heavy rainfall.
- The public to reduce their use of plastic packaging, and reuse and recycle wherever possible. First steps can be as simple as avoiding plastic shopping bags, bottled drinking water and over packaged goods.
So next time you’re at the beach, take a good look around you. If you want to preserve that idyllic seaside experience for future generations and ensure our seas stay fit and healthy, make sure you don’t add to the already huge problem of marine debris in our environment. On a national level, more effective legislation and enforcement of litter laws is needed. But every piece of litter has an owner – every single person can make a difference and has a responsibility not to drop litter or flush it down the toilet. Remember: bag it and bin it; don't flush it!
Useful Links
Beach litter categories
5 Gyres Project
Project AWARE
Marine Conservation Society
No comments:
Post a Comment