Surveys show plastics
are the most common solid pollutants washing up on beaches. Plastics
are very difficult for the natural world to break down and they
last a long time, especially underwater where the sun cannot break
them down. Beaches are littered with plastic items everywhere,
even on small uninhabited islands in the middle of the Pacific
Ocean.
Plastics are strong
and come in many shapes and sizes that are harmful to sea creatures.
In New Zealand beach surveys, small plastic pellets used in manufacturing
plastic bottles and other items are the most numerous item found
followed by filter tips from cigarettes. In 1992, in a global
survey, cigarette butts made up 18.08% of all debris collected.
Plastic fishing
gear, the yokes that hold six packs of drinks, bread bags, plastic
shopping bags and styrofoam cups have been estimated to kill up
to one million sea birds and 100,000 marine mammals throughout
the world each year.
Researchers estimate
that three times more garbage is being thrown into the ocean each
year than the amount of fish being taken out, and much of this
garbage is plastic.
People throw their
left-over cigarette butts on the ground, flick them out of car
windows, and dump their car ashtrays onto parking lots. The filters
are plastic and do not break down. When it rains, the filters
wash into storm drains and down to the sea. Some wash up on beaches,
but most float in the sea or sink to the sea floor. Fish and other
creatures may eat these, thinking they are food.
Sea creatures can't
digest plastics. It clogs their intestinal tract and kills them.
In 1994, two whales washed up on New Zealand beaches, having died
from eating plastic bags. Thousands of sea turtles and birds have
died from eating plastic bags, thinking they were jellyfish.
Sailors report plastic
bags floating at sea almost everywhere in the ocean, even far
from land. Most of these plastic bags are blown into the sea from
rubbish dumps and from poorly maintained trash containers. People
drop empty plastic bags on the ground or put them in open trash
containers. The wind blows the empty bag into the air, like a
balloon, and they eventually fall into the sea.
Old fishing nets
and lines are the most dangerous kinds of trash. These can go
on catching fish and tangling birds, turtles, seals, and even
dolphins for years and years. Fishing bait bags and boxes are
especially bad. Fishermen throw the old bait bags into the water
because the bags smell strongly of fish. The strong fishy smell
and taste, fools sea creatures into thinking the plastic is food.
The Marine Conservation
Society gives the following length of time for common types of
litter to decompose:
Earthkids, New Zealand Conservation Stories, Activities and Games by Andrew Crowe.
Marine Debris on New Zealand Coastal Beaches, A Greenpeace Survey, Adopt-A-Beach Campaign, Peter Smith & Jes Tooker.
Summary of Marine Debris Research 1989-1994, Gael Arnold, Jill Calveley, Greg George, Fay Sara.
Pocket Guide to Marine Debris 1993. Center for Marine Conservation. 1725 DeSales Street NW. Washington DC 20036.