The Earth's population is using the equivalent of 1.5 planets' worth of natural resources, but the long-term decline of animal life appears to have been halted, a WWF report shows.

The latest Living Planet report, published today by the conservation group, also reveals the extent to which modern Western lifestyles are plundering natural resources from the tropics at record levels.

The report shows shows the impact of living off the planet's "savings": in the last 40 years human consumption has doubled, while the Living Planet index – measuring the decline and increase of thousands of species on land, in rivers and at sea – has declined by 30% overall, and by a massive 60% in the tropics.

However the index –compiled by the Zoological Society of London (ZSL) and likened to a stockmarket charting the progress of the natural world – shows that animal populations have risen significantly in the richer nations in the temperate zones north and south of the tropics, and globally appear to have stabilised in the last few years.

Despite the suggestion of good news, WWF and supporters at the launch warned that there were still severe threats, especially from climate change and water shortages.

"Healthy ecosystems form the basis of all we have - lose them and we destroy our life support system," said Jonathan Baillie, ZSL's conservation programme director.

"This is like spending the savings: we're spending the natural capital we have on this planet," said Jim Leape, WWF's director, at the launch of the report in Bristol. "That's an economic crisis in the making."

Measurements of the "ecological footprint" of different countries – the area required to provide the resources consumed by the population or average person in a year, compiled by the Global Footprint Network, shows the richest countries consume, on average, five times the quantity of natural resources as the poorest countries. At the extremes are the United Arab Emirates, with an average footprint of more than 10 hectares, and Timor-Leste at less than one hectare. The global average is about three hectares, and the UK figure is around five.

"There's going to be global trade and that's not always a bad thing," said Colin Butfield, head of campaigns for WWF. "[But people] in many subsistence countries depend on their local water source and if upstream you have got a big industrial cotton or soy growing plant, we're starting to affect in many many cases around the world the ability for poor people to develop, feed themselves, industrialise, to supply basic products we use every day: soy beans for cattle, cotton for clothing, and so on.

"We're also taking away the natural capital of those countries, and only a small number of people in those countries benefit."

The latest index compiled the results for nearly 8,000 populations of more than 2,500 different species of mammals, reptiles, amphibians, birds and fish. The real picture is, however, likely to be worse, because the latest report includes new populations, and because there are still many tropical species which have not been identified by scientists yet, said Butfield. It also does not directly measure the fate of plants, or pollution.

Nick Ross, the TV presenter who joined the launch event, called it "a bonfire of biodiversity".

"The trajectory is so alarming that even if people pick little holes in the methodology the message that comes across here is overwhelming," he said.

The report says the biggest impact on the global footprint of humanity is an 11-fold increase in carbon emissions in the last four decades. In another 40 years the footprint would double again, forecasted Leape.

The report, which is published just weeks before a major conference on slowing or halting the loss of biodiversity in Nagoya, Japan, calls for a series of changes to help address the problems, including more protected areas, zero net deforestation, eliminating overfishing and destructive fishing practices, and finding ways to put a value on biodiversity and ecosystem services.

There also needed to be more support to sustainable alternatives to modern consumption, such as timber, fish, soy, and other commodities from well-managed sources, said WWF. Although government regulation was the "ideal" way to achieve this, consumers and businesses also needed to insist on such standards, said Butfield. "The reality of politics is government will only move a certain amount of the way, depending on how much they think consumers and businesses are behind them," he said.