EARTH’S SPECIES FEEL THE SQUEEZE
EARTH’S SPECIES FEEL THE SQUEEZE
2005-05-25 at 12:13:00 pm #9706Earth’s species feel the squeeze
If we continue with current rates of species extinction, we
will have no chance of rolling back poverty and the lives of all humans will be
That is the stark warning to come out of the Millennium Ecosystem Assessment
(MA), the most comprehensive audit of the health of our planet to date.
Organisms are disappearing at something like 100 to 1,000 times the
“background levels” seen in the fossil record.
Scientists warn that removing so many species puts our own existence at risk.
It will certainly make it much harder to lift the world’s poor out of
hardship given that these people are often the most vulnerable to ecosystem
degradation, the researchers say.
The message is written large in Ecosystems and Human Well-being: the
Biodiversity Synthesis Report.
Biodiversity and human well-being just cannot be
Dr Kaveh Zahedi, World Conservation
Monitoring CentreIt is the latest in a series of detailed documents to come out of
the MA, a remarkable tome drawn up by 1,300 researchers from 95 nations over
The MA pulls together the current state of knowledge and in its latest
release this week focuses specifically on biodiversity and the likely impacts
its continued loss will have on human society.
In one sense, and precisely because it is a synthesis, the new document
contains few surprises. It is, nonetheless, a startling – and depressing – read.
MA BIODIVERSITY SYNTHESISThe last 50 years have seen the biggest biodiversity upheaval in
human historyOver half the world’s biomes (vegetation types) have experienced
about 20-50% conversion to human useThe rates of change have been greatest in tropical and
sub-tropical dry forestsSome 35% of mangroves and about 20% of corals have gone Across a range of taxonomic groups, species are in decline
A third of all amphibians, a fifth of mammals and an eighth of all
birds are now threatened with extinction. It is thought 90% of the large
predatory fish in the oceans have gone since the beginning of industrial
And these are just the vertebrates – the species we know most about. Ninety
percent of species, maybe more, have not even been catalogued by science yet.
“Changes in biodiversity were more rapid in the last 50 years than at any
time in human history,” said Dr Georgina Mace, the director of science at the
Institute of Zoology, in London, UK, and an MA synthesis team member.
“And when you look to the future, to various projections and scenarios, we
expect those changes to continue and in some circumstances to accelerate.
“Future models are very uncertain but all of them tell us that as we move
into the next 100 years, we’ll be seeing extinction rates that are a thousand to
10,000 times those in the fossil record.”
One feature that sets the MA apart from previous projects of its kind is the
way it defines ecosystems in terms of the “services”, or benefits, that people
get from them.
Some of these services are obvious – they are “provisional”: timber for
building; fish for food; fibres to make clothes.
At another level, these services are largely unseen – the
recycling of nutrients, pollination and seed dispersal, climate control, the
purification of water and air – but without these “support” and “regulating”
systems, life on Earth would soon collapse.
And although we may be some distance away from an “end scenario”, there is no
doubt the rapid expansion of the human population and its high consumption of
natural resources have taken a heavy toll on ecosystems and the organisms that
“Biodiversity and human well-being just cannot be separated,” said Dr Kaveh
Zahedi, the officer in charge of the Unep World Conservation Monitoring Centre
in Cambridge, UK.
“We are befitting from a whole range of services that up until now have
almost been invisible; we haven’t considered them. And then they suddenly pop up
on our radar screens – we have a tragedy in Asia with a tsunami and we realise
that those mangroves that were cut down had a value; they provided a service in
terms of coastal protection.”
Land-use (habitat) changes, climate change, pollution and over-exploitation –
they are all pushing down on biodiversity and the pressure shows little sign of
“The magnitude of the challenge of slowing the rate of biodiversity loss is
demonstrated by the fact that most of the direct drivers of biodiversity loss
are projected to either remain constant or increase in the near future,” the MA
biodiversity synthesis report says.
If you do things the right way, if you chose the
right options for poverty alleviation, you can also maximise biodiversity and
Dr Georgina Mace, Institute of
ZoologyRemoving huge swathes of forest has a blunt and clear impact on
biodiversity by taking out the habitat formerly occupied by plants and animals.
But there are subtle changes taking place, too.
The distribution of species around the globe is becoming more homogenous, as
invasive creatures hitch a ride on fast human transport and trade routes.
Genetic diversity, also, is declining rapidly.
This is most obvious in domesticated plants and animals where the pursuit of
high yields and the pressures of global markets have pushed farmers towards a
limited range of cultivars and breeds.
And so it is not simply that species are fewer in number, their changed
circumstances may also have reduced their resilience and their ability to cope
with future change.
In 2002, world governments, through the Convention on Biological Diversity,
set themselves the target of making a “substantial reduction in the rate of loss
of biological diversity” by 2010.
The MA illustrates just how tough it will be to meet that target. What is
more, there may even be occasions when progress towards that target conflicts
with the even loftier 2015 Millennium Development Goals of cutting into world
hunger and poverty, and improving healthcare.
BIODIVERSITY AND POVERTYBiodiversity and human well-being are inextricably linkedHumans benefit from ecosystem services, but unsustainable use
drives biodiversity lossPeople living in rural areas in developing nations are often
most dependent on biodiversityAnd they are usually most vulnerable to ecosystem service
degradationThey cannot afford to move out or import new servicesA classic example is the development of rural road networks – a
common feature of hunger reduction strategies – which are likely also to
accelerate rates of biodiversity loss by fragmenting habitats and by opening up
new areas to unsustainable harvests.
This sort of thing has been well documented in Africa where the bushmeat
trade that endangers many species follows the development of transport
“This is a very important issue,” said Dr Mace. “It’s clear there are going
to have to be trade-offs and compromises but it’s not a simple relationship.
It’s not a case that you can have 20% poverty and 80% biodiversity.
“If you do things the right way, if you chose the right options for poverty
alleviation, you can also maximise biodiversity and sustainability.”
And Dr Neville Ash, another MA synthesis team member, added: “The bottom line
is that you cannot achieve long-term poverty alleviation without sustainability.
“In order to reduce hunger and poverty and increase access to clean water and
sanitation, we need to have a strong base of environmental sustainability which
is providing these services on which people rely for their well-being.”
It is very evident, too, that we need to get a move on.
The wheels of global governance turn slowly, as was seen with the Kyoto
Protocol on climate change which finally entered into force in February after
many years of negotiation.
The MA has identified possible solutions – from significant shifts in
consumption patterns and better education, to the adoption of new technologies
and a large increase in the areas enjoying protection.
And if some of the ideas sound “old hat”, such as the abolition of farming
subsidies that drive crop production to the detriment of field biodiversity –
that is because they are.
“Most of the approaches to achieving more sympathetic management of the
natural environment and the conservation of biodiversity – I think we and
governments know them already,” commented Graham Wynne, the chief executive of
the UK bird conservation group, the RSPB.
“The real challenge is to deploy them more extensively and more
“And you can’t get away from the fact that we simply need more money.
“The sums of money we throw at the environment in the West are relatively
modest; and the sums of money the West is prepared to devote to developing
countries is pitiful.”