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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.
THE PROBLEM OF PLASTIC
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.
THE THREAT TO WILDLIFE
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.
CONSERVATION ACTION
The problem of plastic pollution is serious and
requires further urgent study. Immediate action is
also required such as :
WHAT YOU CAN DO
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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.
FURTHER READING AND USEFUL
ADDRESSES
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Dolphin Action and Protection Group, P O Box
22227, Fish Hoek 7975.
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The Packaging Council of SA, P O Box 782205,
Sandton,2146.
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Everyone's guide to Recycling - obtainable
from Earthlife Africa P O Box 176,
Observatory, 7935.
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National Council to Coordinate Recycling,
Private Bag X40028, 0007
ACKNOWLEDGEMENTS
The production
of the original Enviro Facts sheets are sponsored by
Pick'n Pay and developed with the help of several
conservation bodies through the Environmental
Education Association of Southern Africa (EEASA).
Gavin Maneveldt
has given valuable editing input into this version.
Photographs and slides were kindly given by Martin
Hendricks, Derek Keats and Gavin Maneveldt (all from
the University of the Western Cape).
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