Ocean News

Our ocean’s plastic peril

31st December 2009

Today’s throw-away culture is a nightmare for our oceans. From the ocean’s darkest depths to tropical blue waters and ice-covered shelves, from sunlit beaches to the shores of the remotest islands – plastic has conquered the world.

Plastic items are the most common objects sighted at sea, and this new colonisation is a scourge for both humanity and wildlife. It not only turns the beauty of once pristine beaches into the ugliness of a dumping ground, but at sea our rubbish is also causing incalculable damage to marine ecosystems.

The consequences of allowing our refuse to reach the sea to seabirds, turtles, whales and dolphins is often fatal. In fact, plastic has harmful and detrimental effects on at least 267 marine species. Seabirds often mistake plastic, including plastic packing pellets, bottle tops, plas- tic dinosaurs, lego blocks, clothes pegs and fishing line, for food and feed it to their chicks.

A recent study has shown that 90 per cent of albatross chicks had plastic debris in their stomachs. It punctures the bird’s stomach or blocks its oesophagus or gizzard, leaving little room for food or liquid and causing a slow death.

Scientists have calculated that on the Midway atoll alone, half way between North America and Japan, albatross feed their chicks about five tonnes of plastic a year.

Dolphins and seasl become entangled in discarded six-pack carrier rings and strapping bands that act as floating snares causing them to starve or suffocate.

The plastic bag, named in some countries as the new national flower after the millions of bags that cling to trees and hedges, is fast becoming the ocean’s new jellyfish. Sea turtles mistake plastic bags for jellyfish, one of their favourite foods. Bags, however, do not pass through their gut, but block the intestine and often cause the turtle to starve to death. One autopsy per- formed on a dead turtle revealed 1,000 pieces of plastic in its stomach.

Researchers have found that more than a million seabirds and 100,000 mammals and sea turtles die globally each year from entanglement in or ingestion of plastics.

Plastic was first mass produced in the 1950s. None of its many forms, including monofilament fishing line, nylon banding straps, bottles and floats, packing materials, plastic bags, and flip flop sandals, are biode- gradable. It takes a 1,000 years or longer to break down in the environment, but it never disappears. Worn down by sunlight and salt into minute fragments, or plastic dust, that sink beneath the surface.

In the North Pacific gyre these plastic pieces outnumber plankton, the building blocks of ocean life, six to one. Caught in the Pacific doldrums a 21st-century continent twice the size of Texas exists made from six million tones of discarded plastic.

Plastic dust, not only inherently contains toxic chemicals, but it also acts as a sponge, absorbing heavy metals and other pollutants from the ocean. This toxic soup becomes more concentrated as it moves up the food chain, from small to larger fish, through to birds and marine mammals. Studies have even shown plastic dust in the stomachs of filter feeders such as barnacles, detritivores and lugworms.

Moving undetected by satellites and ships these particles, also known as mermaid’s tears, are more insidi- ous than choking and strangulation by whole plastic waste.

“Every single piece of litter has an owner and every single person can make a difference to our oceans by taking their rubbish away with them and ensuring that they dispose of it carefully, ” says Save Our Seas Foundation Director Chris Clarke. SOSF calls on people to help save our seas by stopping plastic from reaching the ocean and by being involved with local beach clean up operations.