A few weeks ago my family and I went for a walk along Croyde beach in Devon and sadly, we discovered horrible amounts of marine debris littered across the shore, most of which was plastic. Plastic waste tends to get broken down, so the debris comprises thousands of small pieces of broken plastic; all you had to do was look a little closer to see masses of sharp coloured pieces littered amongst the seaweed, and more was being washed ashore as we stood and watched.
We must have encountered at least 20, if not more, dogs as we walked along the beach, including our own fluffy companion. Combined with all the wildlife that live on and around the beach, just consider how many animals are at risk of harming themselves via ingestion or injury from this pollution alone.
The explosion of plastic pollution along our shorelines is just a symptom of the larger problem. Our oceans are bursting with foreign bodies originating from human activity, mostly from land based industries; studies claim that 80% of marine pollution originates from the land. A particularly disturbing statistic was revealed in 2015 by a group at UC Santa Barbara’s National Center for Ecological Analysis and Synthesis (NCEAS) who claimed that 8 million metric tons of plastic pollutes our oceans every year.
Sources and destinations
Its persistant nature is the very quality that enhances the appeal of plastic. It is versatile, inert, and practically indestructible. Scientists suggest that, on average, 13,000 pieces of plastic litter every square kilometre of the ocean, which, considering we waste approximately 50% of the plastic we use, is hardly surprising. This endless assault on the ocean is almost impossible to tackle, as we produce plastic waste through almost everything we do. Our failure to dispose of waste effectively or responsibly is the primary cause of marine pollution; inputs include tourist related litter such as food and beverage packaging, fishing related debris, garbage from ships, and loss from overfilling landfills.
Once plastic waste enters our waterways, through drainage systems or run off from the land, it is distributed rapidly. Eventually, it all reaches the ocean where it travels across the globe, or accumulates in ‘garbage patches’ with the help of currents called gyres. The Great North Pacific Garbage Patch is the largest, spanning the waters from northern America’s west coast to Japan. Marine debris is drawn into the centre of these currents where it becomes trapped, almost indefinitely, forming a cloudy soup of polluted water.
Danger to wildlife
Both marine life and terrestrial life are greatly affected by plastic pollution. Entanglement, suffocation, and internal damage from ingestion are the main causes of fatality in marine animals, and endanger all wildlife from microscopic organisms, to large mammals such as whales. A particularly notorious item is the plastic bag. Turtles mistake plastic bags for jelly fish whereby they ingest them, and often suffocate in the process. This is not exclusive to plastic bags however, many marine animals mistake plastic items for food; birds and turtle carcasses are washed ashore with their digestive systems bursting with ingested plastic. Thankfully, many countries including China, Africa, and parts of the US, have introduced charges, even bans, against the use of plastic bags.
It’s not just the plastic that poses a threat, chemicals such as polychlorinated biphenyls (PCB’s) and other ‘persistent organic pollutants’ are released into the environment and, via ingestion, enter the food chain. While the long term physiological effects are largely unknown, after the chemicals have entered the food chain the likelihood is that they will bioaccumulate as they move up the food chain, affecting predators, and even humans through ingestion.
How plastic affects certain species
50% – 80% of beached turtles are found with plastic cups and other items lodged in their digestive tracts.
Juvenile turtles become entangled in the loops of six pack rings. As they cannot escape, or rid themselves of the ring, they grow around the ring; their shells become extremely distorted and some will perish from suffocation.
Ingestion of plastic debris is an enormous problem for sea birds; having ingested a stomach full of plastic, they become bloated and feel ‘full’, where in fact, they are starving to death.
The Laysan Albatross is especially vulnerable to this issue. As they swoop down towards the sea in search of fish, squid, and other seafood, they skim the surface of the water. In doing so, they accidentally collect, and ingest floating plastic.
Marine mammals (such as whales and dolphins)
Marine mammals are in danger of entanglement from fishing nets that are disposed of from trawling activity.
Dolphins are also captured as ‘bycatch’ in the course of such activities, many of which are tossed back into the ocean, dead.
Harbour dolphins and porpoises are even in danger of becoming bycatch in semi-permanent fishery constructs, such as bottom-set gillnets.
What can we do?
1. Manual clean ups
If you’re heading out for a walk along the beach (or anywhere in fact), grab a bag on your way out, and pick up what litter you find. Anyone can organise a beach clean up! Just promote your cause and rally your army.
Thousands of people now volunteer to take part in manual clean ups – The Ocean Conservancy arranged a manual clean up in 2014, where 560,000 volunteers across 91 countries collected more than 16 million pounds of debris from coastal areas.
2. Consume less plastic
While manual clean ups help, we need to resolve the issue at its source. In basic terms, clean up after yourselves, and try to consume/use less plastic. This is difficult to do (I understand your pain), but it is doable, it just involves a little organisation – use a bag for life to carry your groceries, bulk buy, stop purchasing so many plastic water bottles (it will cost you far far less to purchase a re-usable bottle), and use alternatives to straws, plastic cups etc.
Of course, the ideal scenario would see none of us consuming plastic in the first place, but unfortunately, this is unrealistic. By familiarising yourself with the coded jargon on plastic packaging, you can make sure you recycle effectively.
Clark, R.B. (2001) Marine Pollution: Fifth Edition. Oxford University Press.
NABU International. (2016) Welcome to the online home of the smallest and rarest dolphin on earth. Available at: http://www.hectorsdolphins.com/harmful-fishing-methods.html.
Scheller, A. (2014) This Is How Your Plastic Bag Ends Up In Massive Ocean Garbage Patches. Available at: http://www.huffingtonpost.com/2014/04/22/plastic-ocean-garbage_n_5191294.html
Wanshel, E. (2016) Edible Rings On Six-Packs Feed Marine Life If They End Up In The Ocean. Available at: http://www.huffingtonpost.com/entry/saltwater-brewery-edible-six-pack-rings-beer-plastic-marine-life_us_573b796ce4b0ef86171c5fe4