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State of the Planet
1
http://www.bbc.co.uk/nature/programmes/tv/state_planet/programmes.shtml
State of the Planet
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Pollution / Habitat Loss / Introduced Species / Over Harvesting /Fragmentation
Attenborough Interview
Ask the Experts
Pollution
Problem
Pollution can be local or widespread. Substances dumped into a river will often end up in the sea.
The biggest pollution problem is global warming. This happens when greenhouse gases, such as CO
2 are released into the atmosphere, trapping heat and causing the planet to warm up. Since species
are adapted to particular climates, when the Earth warms up they have to move to keep comfortable.
This can be difficult if natural habitats are isolated by human settlements and agriculture.
Facts and figures
Chemical pollutants have been responsible for affecting the reproductive organs of fish, alligators
and polar bears, preventing them from producing babies. Chemical pollution in the environment
also affects humans - 46 US states have issued warnings against eating local fish because of dioxin
contamination, and in Europe, human breast milk passes on more dioxin to our babies than is
legally allowed for cow's milk. Despite this, the amount of pesticide sprayed on our crops around
the world has increased 26 times in the last 50 years.
Species affected
Species living in water are often most strongly affected because water spreads pollution easier than
land, and because we often dump our pollution into water. Global warming will affect every species
on Earth to some extent, and although some species will thrive in warmer climates, many will not.
Coral reefs have already been very hard hit by climate change, and polar bears have received the
double-whammy of climate change and chemical pollution.
Solutions
Most human activities produce some waste products, but it is important to make sure that we have
as little pollution as possible. Many people are switching to 'clean technology'. That means having
the same benefits from our modern life-style without the pollution. Electric cars, environmentally
sensitive washing powders and solar-powered energy are examples. Less pollution is not only good
for wildlife and nature - human health benefits from less pollution as well. That means lower
medical bills, and a better quality of life.
Habitat Loss
Problem
Every living thing needs a place to live, find food, and reproduce. When we take over natural areas
for our own use, we take away those areas for other living creatures. Habitat loss is the greatest
threat to the natural world. We are taking over habitat at an alarming rate to provide ourselves with
homes and agriculture as well as resources from forests, and other natural areas.
Facts and figures
State of the Planet
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All habitat-types are affected by human activity to different extents. Around half of the forests that
once covered the Earth are now gone. Although forests can recover, and even be harvested
sustainably, the rate of loss is 10 times higher than the rate of regrowth. Around 60% of Europe's
wetlands are damaged even though they are often essential for providing clean drinking water.
Species affected
Recent estimates suggest that at least 120 out of 620 living primate species (apes, monkeys, lemurs
and others) will go extinct in the wild in the next 10 to 20 years, at current rates of habitat loss.
Large animals are often hit hardest by loss of habitat because they need large areas in which to have
a healthy breeding population. Examples include tigers, mountain gorillas, pandas, Indian lions,
tropical orchids and spotted owls. The only species not truly affected by habitat loss are those which
benefit from human activity, such as cockroaches, rats and house-finches.
Solutions
Animals become more sensitive to where we go about our business as well as how. Everyone needs
space and that includes the other creatures of this planet. Restoring damaged habitats is also an
important step. Allow forests to regrow, clean up rivers, lakes and seas, and help to protect what still
remains.
Introduced species
Problem
When new species are introduced to places where they have never existed naturally, they can
sometimes cause a real problem for native wildlife. Not only can they affect local species by
competing with them for food and resources, or even eating the natives, but they can also be very
damaging to crops, people's homes and even cause diseases.
Facts and figures
A recent estimate of the damage to the United States economy from introduced pest species was as
much as 123 billion US$ per year. Before humans arrived in Hawaii, the islands received a new
species by sea or wind once every 70 000 years - these days 100 new species are introduced there
every year causing great damage to the native plants and animals.
Species affected
Mink have been considered responsible for reducing the native water vole population in the UK due
to competition for habitat and food. Many rare birds have been threatened by introduced rats, cats,
snakes and other species. Native plants can find it hard to compete with other exotic plants. But
humans are also affected. Termites, aggressive bees, insects that damage our crops, and even
diseases that originate in foreign lands can be very harmful. The Nile perch was introduced into
Africa's Lake Victoria for food and sport fishing. It has eaten its way through 200 native fish species,
and is still going. The brown tree snake from Papua New Guinea arrived on the Pacific Island of
Guam and has eliminated 12 out of 14 of the local bird species there.
Solutions
There must be tight regulation on bringing plants and animals across international borders, airports
and shipping ports. The public mustn't bring exotic species back home with them without a license.
State of the Planet
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New Zealand is leading the world in ridding their country of pest species such as rats and cats, but it
is a slow and expensive process, and preventing new arrivals is the cheapest and easiest solution of
all.
Over Harvesting
Problem
All living things need resources to survive, whether for food or to provide shelter. Humans are just
extremely efficient at getting hold of them. One third of the world's resources have been used up in
the last 30 years. One calculation estimates that in 50 years' time, we will need another planet Earth
to sustain the world's population if it keeps using resources the way it does today. But people in
countries such as America, Japan, and in Europe can use up to 30 times the amount of resources as
people from poor countries. We simply catch too many fish, use too much wood and waste too
much fresh water.
Facts and figures
At least 70% of the world's important fish stocks are over-exploited already. Paper use has grown
six times since 1961. Consumption of freshwater has tripled since 1950, and it is becoming a very
scarce resource: one billion people world-wide don't have access to clean drinking water. All
together, up to half of all new plant growth each year on the planet is taken for human use.
Species affected
Tropical hardwood and fish for human consumption. The commercial bushmeat trade takes many
rare wild species for luxury food. Tropical orchids, coral reef fish and many reptiles and birds, such
as macaws, are taken for pets and our entertainment.
Solutions
Sustainable natural resource use. Put simply, if we take from the wild, we must do it in ways that
allows natural populations to recover and last long into the future. Blue whales and other large
marine creatures were brought back from the brink of extinction because we stopped harvesting
them to excess. If you catch fish faster than they can reproduce and replace what is taken, there will
be no fish for anybody to use in the future. The same goes for forests. Energy sources such as wind
and solar power can last forever, and mean that we don't have to use up the world's supply of oil and
gas. They are also cleaner and healthier.
Fragmentation islandisation
Problem
This is the breaking up of large natural places into smaller fragments or islands of habitat. National
parks and nature reserves are some examples. Just as your own back garden is too small for a
population of tigers to survive, small areas of habitat cannot hold the same number of species that
large ones can. Many of the world's nature reserves could lose their plants and animals gradually
over time if they are too small.
Facts and figures
Although half of the Earth's original forests still remain, less than half of these are in large patches
State of the Planet
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that can hold large numbers of species. Many of the smaller national parks of America have lost
numbers of their larger mammal species, or they can only be maintained by strenuous efforts.
Species affected
The larger animals are the ones that need larger areas of habitat. But since no species exists in
isolation, if a species disappears then the other species that depend on it and interact with it are also
affected. When Jaguars disappeared from the tiny island of Barro Colorado in Panama, the whole
ecosystem changed. Even if small populations of plants and animals can hang on, their populations
may be too small to survive for long. Tigers , pandas and mountain gorillas may number several
hundred in the wild, but often the individuals are separated from each other by farms and villages.
Solutions
Make natural habitats as big as possible, and join together the small ones with habitat corridors.
This allows animals to move between isolated areas which keeps their populations large and healthy.
In some parts of the world, adjoining countries are connecting their national parks across
international borders to make really big parks in a project called 'The Peace Parks Initiative'. This
appears to be benefiting local wildlife, and the local people who depend on it.
State of the Planet
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Interview with Sir David Attenborough
After nearly 50 years of groundbreaking natural history broadcasting, David Attenborough takes
stock of the state of the planet and assesses why the Earth needs our help.
The Elephant
"The question is, are we happy to suppose that our grandchildren may never be able to see an
elephant except in a picture book? And if the answer is no, then people world-wide have got to
say: 'Yes, elephants are a glory and a splendor and a wonder and we should not be responsible
for their disappearance. And we are prepared to do something about it'."
With the serious pronouncement that a mass extinction of life -involving the loss of up to 50 per
cent of all species on the planet - may occur in the next 100 years, David says it's time to think
about the natural world and where we are in the life of the planet. He points out it's not just the
"glamorous" or "popular" species that need help:
Rhinoceros
"The only way to save a rhinoceros is to save the environment in which it lives because there's
a mutual dependency between it and millions of other species of both animals and plants. And
it is that range of biodiversity that we must care for - the whole thing - rather than just one or
two stars."
"It's not just that we are dependent on the natural world for our food and for the very air we
breathe - which is, of course, the case - and that the very richness of the natural world
continues to provide us with all kinds of assistance. But it's a moral question about whether we
have the right to exterminate species and leave a world that is more impoverished than the one
we inherited - simply because of our carelessness and greed - to our grandchildren. People
must feel that the natural world is important and valuable and beautiful and wonderful and an
amazement and a pleasure."
David Attenborough - who is known to put his pensioner's rail card to good use - raises the fuel
debate:
David Attenborough holding a silver spotted skipper butterfly
"There are a multitude of things that the individual can do. There is the present debate going on
about petrol, for instance. The fact is that we are poisoning the atmosphere and the less fumes
we put in it, the better. And we are using up our fossil fuels."
Using eco-friendly washing-up liquid and recycling the Sunday supplements alone won't save the
planet but, he argues, the individual can make a difference:
"There are things to be done at all levels: from using less power and being more modest about
the demands that we put on the environment; to not using CFCs; voting for the right politician,
who you think is supporting these ideals; and giving a few pence, every now and again, to
appeals. It's about cherishing the woodland at the bottom of your garden or the stream that runs
through it. It affects every aspect of life."
If the future of life on Earth depends on our capacity to care, then David Attenborough is certainly
State of the Planet
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teaching by example:
David Attenborough
"It seems to me that the natural world is the greatest source of excitement; the greatest source
of visual beauty; the greatest source of intellectual interest. It is the greatest source of so much
in life that makes life worth living."