UK scientists have issued a clarion call to the world to recognise the galloping rate of species extinction.
By Alex Kirby
BBC News Online environment correspondent
They have devised a framework for measuring biodiversity, to show just how fast species are disappearing.
They say we can make better use of available knowledge, for example through web-based technology.
But another problem, they believe, is the existence of huge gaps in what we know.
The call comes from the Royal Society, the UK's national academy of science, in a report, Measuring Biodiversity for Conservation.
It is published on the eve of a meeting in London of the United Nations Convention on Biodiversity (CBD).
Listed to disappear
The meeting is reviewing progress towards the target of "a significant reduction in the current rate of biodiversity loss by 2010", agreed at the 2002 World Summit on Sustainable Development in Johannesburg.
The group which produced the Royal Society report was chaired by Professor Peter Crane, director of the Royal Botanic Gardens, Kew.
He said: "The living world is disappearing before our eyes. Around one in 10 of all the world's bird species and a quarter of its mammals are officially listed as threatened with extinction, while up to two-thirds of other animal species are also endangered.
"These losses have accelerated over the last 200 years as a direct and indirect consequence of the growth in human populations, wasteful use of natural resources and associated changes to the environment.
"Although we have a feel for the scale of the loss, we often lack specific and accurate information about how badly individual species and their habitats are suffering."
So it was hard to decide whether efforts to save these species were working.
Professor Crane said: "It is essential that they do succeed, because many of the world's poorest people directly depend for their livelihoods on the diversity of plant and animal species and their habitats."
The framework it has developed, the society says, can be used for long-term monitoring as well as emergencies like oil spills.
It has three stages:
The Royal Society report says human dependence on biodiversity is "absolute", not only for direct benefits like food but also for climate regulation, water purification, soil formation, flood prevention and nutrient cycling.
scoping, which defines who the interested parties are
a conceptual model, using available knowledge and forcing assumptions to be recognised and made explicit
implementation, involving data gathering, analysis and reporting back.
It says these benefits must be available to future generations, yet people alive today must also gain.
It says: "We recognise the fundamental tension between intergenerational equity and the humanitarian imperative of equality here and now."
The report also calls for balance between synthesising information already available, using IT and the internet, and collecting new data.
Saved: The buffalo avoided extinction
It says there are "major areas of ignorance", especially for the areas where species diversity is greatest.
Professor Georgina Mace, director of science at the Zoological Society of London, was a member of the Royal Society working group.
She told BBC News Online: "We support the idea the world is on the breaking crest of the sixth great wave of extinction.
"The rate of loss is still accelerating, and so is our impact on habitats. But there's a time lag between the damage happening and the extinction occurring.
"It's a pretty straightforward problem, and solving it requires a compilation of information that we haven't done.
"And there's a funding gap too. It's easy to get money for new science, but very hard to get it for synthesising data."