Earth lost 50% of its wildlife
in the past 40 years, says WWF
Species across land, rivers and seas decimated as humans kill for food
in unsustainable numbers and destroy habitats
Damian Carrington
The Guardian, Monday 29 September 2014 / http://www.theguardian.com/environment/2014/sep/29/earth-lost-50-wildlife-in-40-years-wwf
The number of wild animals on Earth has
halved in the past 40 years, according to a new analysis. Creatures across
land, rivers and the seas are being decimated as humans kill them for food in
unsustainable numbers, while polluting or destroying their habitats, the
research by scientists at WWF and the Zoological Society of London found.
“If half the animals died in London zoo next week it
would be front page news,” said Professor Ken Norris, ZSL’s director of
science. “But that is happening in the great outdoors. This damage is not
inevitable but a consequence of the way we choose to live.” He said nature,
which provides food and clean water and air, was essential for human wellbeing.
“We have lost one half of the animal
population and knowing this is driven by human consumption, this is clearly a
call to arms and we must act now,” said Mike Barratt, director of science and
policy at WWF. He said more of the Earth must be protected from development and
deforestation, while food and energy had to be produced sustainably.
The steep decline of animal, fish and bird
numbers was calculated by analysing 10,000 different populations, covering
3,000 species in total. This data was then, for the first time, used to create
a representative “Living Planet Index” (LPI), reflecting the state of all
45,000 known vertebrates.
“We have all heard of the FTSE 100 index,
but we have missed the ultimate indicator, the falling trend of species and
ecosystems in the world,” said Professor Jonathan Baillie, ZSL’s director of
conservation. “If we get [our response] right, we will have a safe and
sustainable way of life for the future,” he said.
If not, he added, the overuse of resources
would ultimately lead to conflicts. He said the LPI was an extremely robust
indicator and had been adopted by UN’s internationally-agreed Convention on
Biological Diversity as key insight into biodiversity.
A second index in the new Living Planet
report calculates humanity’s “ecological footprint”, ie the scale at which it
is using up natural resources. Currently, the global population is cutting down
trees faster than they regrow, catching fish faster than the oceans can restock,
pumping water from rivers and aquifers faster than rainfall can replenish them
and emitting more climate-warming carbon dioxide than oceans and forests can
absorb.
The report concludes that today’s average
global rate of consumption would need 1.5 planet Earths to sustain it. But four
planets would be required to sustain US levels of consumption, or 2.5 Earths to
match UK
consumption levels.
The fastest decline among the animal
populations were found in freshwater ecosystems, where numbers have plummeted
by 75% since 1970. “Rivers are the bottom of the system,” said Dave Tickner,
WWF’s chief freshwater adviser. “Whatever happens on the land, it all ends up
in the rivers.” For example, he said, tens of billions of tonnes of effluent
are dumped in the Ganges in India
every year.
As well as pollution, dams and the
increasing abstraction of water damage freshwater systems. There are more than
45,000 major dams – 15m or higher – around the world. “These slice rivers up
into a thousand pieces,” Tickner said, preventing the healthy flow of water.
While population has risen fourfold in the last century, water use has gone up
sevenfold. “We are living thirstier and thirstier lives,” he said.
But while freshwater species such as the
European eel and the hellbender salamander in the US have crashed, recoveries have
also been seen. Otters were near extinct in England but thanks to conservation
efforts now live in every county.
The number of animals living on the land
has fallen by 40% since 1970. From forest elephants in central Africa, where
poaching rates now exceed birth rates, to the Hoolock gibbon in Bangladesh and
European snakes like the meadow and asp vipers, destruction of habitat has seen
populations tumble. But again intensive conservation effort can turn declines
around, as has happened with tigers in Nepal .
Marine animal populations have also fallen
by 40% overall, with turtles suffering in particular. Hunting, the destruction
of nesting grounds and getting drowned in fishing nets have seen turtle numbers
fall by 80%. Some birds have been heavily affected too. The number of grey
partridges in the UK sank by
50% since 1970 due to the intensification of farming, while curlew sandpipers in
Australia
lost 80% of their number in the 20 years to 2005.
The biggest declines in animal numbers have
been seen in low-income, developing nations, while conservation efforts in rich
nations have seen small improvements overall. But the big declines in wildlife
in rich nations had already occurred long before the new report’s baseline year
of 1970 – the last wolf in the UK
was shot in 1680.
Also, by importing food and other goods
produced via habitat destruction in developing nations, rich nations are
“outsourcing” wildlife decline to those countries, said Norris. For example, a
third of all the products of deforestation such as timber, beef and soya were
exported to the EU between 1990 and 2008.
David Nussbaum, chief executive of WWF-UK
said: “The scale of the destruction highlighted in this report should be a
wake-up call for us all. But 2015 – when the countries of the world are due to
come together to agree on a new global climate agreement, as well as a set of
sustainable development goals – presents us with a unique opportunity to
reverse the trends.
“We all – politicians, businesses and
people – have an interest, and a responsibility, to act to ensure we protect
what we all value: a healthy future for both people and nature.”
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