By discarding plastic thoughtlessly, especially fishing gear and packaging, people are accidentally causing the deaths of millions of mammals, birds, reptiles and fish every year. Since the development of plastic earlier this century, it has become a popular material used in a wide variety of ways. Today plastic is used to make, or wrap around, many of the items we buy or use. The problem comes when we no longer want these items and how we dispose of them, particularly the throwaway plastic material used in wrapping or packaging. Plastics are used because they are easy and cheap to make and they can last a long time. Unfortunately these same useful qualities can make plastic a huge pollution problem. The cheapness means plastic gets discarded easily and its long life means it survives in the environment for long periods where it can do great harm. Because plastic does not decompose, and requires high energy ultra-violet light to break down, the amount of plastic waste in our oceans is steadily increasing. Studies done locally show about 3 500 particles of plastic per square kilometre of sea off the southern African coast. Surveys of 50 South African beaches from the Eastern Cape to Cape Town show that in five years to 1989 plastic pollution has increased by 190%. More than 90% of the articles found on these beaches contained plastic. Plastic is now found on virtually all South African beaches, even the most remote, and researchers are now also finding plastic rubbish in Antarctic regions. The plastic rubbish found on beaches near urban areas tends to originate from use on land, such as packaging material used to wrap around other goods. On remote rural beaches the rubbish tends to have come from ships, such as fishing equipment used in the fishing industry. This plastic can affect marine wildlife in two important ways: by entangling creatures, and by being eaten. Turtles: Turtles are particularly badly affected by plastic pollution, and all seven of the world's turtle species are already either endangered or threatened for a number of reasons. Turtles get entangled in fishing nets, and many sea turtles have been found dead with plastic bags in their stomachs. It is believed they mistake these floating semi-transparent bags for jellyfish and eat them. The turtles die from choking or from being unable to eat. One dead turtle found off Hawaii in the Pacific was found to have more than 1000 pieces of plastic in its stomach including part of a comb, a toy truck wheel and nylon rope. Marine Mammals: There is great concern about the effect of plastic rubbish on marine mammals in particular, because many of these creatures are already under threat for a variety of other reasons e.g. whale populations have been decimated by uncontrolled hunting. A recent US report concluded that 100 000 marine mammals die each year in the world's oceans by eating or becoming entangled in plastic rubbish, and the position is worsening.When a marine mammal such as a Cape fur seal gets caught up in a large piece of plastic, it may simply drown, or become exhausted and die of starvation due to the greater effort needed to swim, or the plastic may kill slowly over a period of months or years as it bites into the animal causing wounds, loss of blood and/or severing of limbs. "Ghost Nets": A large number of marine creatures become trapped and killed in "ghost nets". These are pieces of gill nets which have been lost by fishing vessels. Other pieces of fishing equipment such as lobster pots may also keep trapping creatures. Marine Birds: World-wide, 75 marine bird species are known to eat plastic articles. This includes 36 species found off South Africa. A recent study of blue petrel chicks at South Africa's remote Marion Island showed that 90% of chicks examined had plastic in their stomachs apparently fed to them accidentally by their parents. South African seabirds are among the worst affected in the world. Plastics may remain in the stomachs, blocking digestion and possibly causing starvation. As particular species seem to be badly affected this may be a threat to whole populations of these birds. The problem of plastic pollution is serious and requires further urgent study. Immediate action is also required such as : -
At the beach dispose of plastics and other litter in the bins provided. If these facilities are inadequate, contact the local authority responsible and lodge a complaint. Take your litter back home with you if there are no receptacles on the beach. Pick up any plastic litter you may see on the beach or in rock pools in the vicinity in which you are sitting or walking. Encourage young children to do likewise.
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