Beach rubbish has been in the spotlight recently with keen crabbers on the shores of Omaha leaving behind pigs' heads and chicken carcasses - apparently irresistible to curious crustaceans. Stumbling upon or indeed over a pig's head while out for a walk is without doubt an extremely unpleasant experience, however a seemingly innocent plastic bag blowing along the beach is destined to have a much more sinister effect when it ends up inside a sea turtle's stomach.
Wondering how my local beach fared after a hot day with lots of human activity, I took my dogs for a run and did a spot of rubbish collecting along the shore and rock pools.
I quickly filled one of the four plastic bags I found in the space of half an hour with glass fragments, three tangled sections of fishing line and a sinker, three aluminum cans, two plastic bottles, a plastic lined drink carton, a plastic drink holder ring, a bottle top and a jandal.
As well as rubbish discarded by beachgoers that day, some had clearly been in the sea for a time and had washed up. Marine rubbish from beach users is generously added to by recreational craft and commercial vessels, via stormwater drains, from oil rigs and blown offshore from the mainland.
Does it really matter? The ocean is huge!
Considering that the ocean comprises almost three quarters of our planet, you may think it can 'soak up' a lot of rubbish before any real damage is done. This may be so, but sadly the amount of rubbish generated is now at the point that the effects are being well and truly felt.
A dramatic example of the cumulative effect of rubbish in the ocean is the 'Pacific Garbage Patch' in the North Pacific Ocean, where American oceanographer Charles Moore estimates about 100 million tons of rubbish, predominantly plastics forms a floating island that takes a week to sail through. Ocean currents have concentrated the waste in this area and the 'plastic soup' continues to grow.
Volunteers try to clear a dam which is filled with discarded plastic bottles and other garbage, blocking Vacha Dam, near the town of Krichim on April 25, 2009. AFP PHOTO / DIMITAR DILKOFF. Photo / Flickr Creative Commons
How long does rubbish last in the sea and what does it do?
Information from the NZ Forest and Bird Society shows just how long carelessly discarded rubbish remains intact in our oceans:
Orange peel: 2 years
Cigarette butts: 1-5 years
Plastic bags: 20-50 years
Tin cans: 50 years
Aluminium cans: 80-100 years
Plastic bottles: 250 years
Glass: I million years
An estimated 80 per cent of marine rubbish is made up of various types of plastic.
Plastics can be mistaken for food by marine animals which then suffer such effects as starvation, dehydration, poisoning and other painful conditions often leading to their death.
Sea turtles for example mistake plastic bags for their jelly fish prey. Sea birds also consume plastic which can resemble small fish. Autopsies of albatross have shown large amounts of plastic contained in their stomachs.
As floating plastic breaks down into smaller pieces it is consumed by plankton feeders, also with disastrous results.
Marine mammals such as dolphins, whales and seals as well as seabirds have been reported entangled in marine rubbish. Discarded fishing equipment and the plastic rings that hold bottles of water together are common examples of this danger. As rubbish sinks to the sea floor it then smothers smaller creatures, blocking out light and preventing the uptake of nutrients.
What you can do?
• Organise a local beach or estuary clean up - this is a great way to work together as a community and get to know your neighbours.
• Choose alternatives to plastic wherever possible.
• No balloon releases - these end up in the sea.
• When on the boat or at the beach, take your rubbish with you.
• Avoid packaging and containers designed for single use and those products with unrecyclable or excessive packaging.
• If you're at the beach or on the water and you see rubbish, pick it up.
The old Reduce, Reuse and Recycle catchphrase is spot on - use less, reuse what you've got and recycle what you can't.
The sea plays an integral role in the health of our planet, it supports millions of creatures, many we are yet to discover and it's a great place to have fun in the summer. Let's not treat it like a rubbish dump.