REPUBLIKA.CO.ID, GENEVA - The average 52 percent decline was much bigger than previously reported, partly because earlier studies had relied more on readily available information from North America and Europe, WWF said. The same report two years ago put the decline at 28 percent between 1970 and 2008.
The worst decline was among populations of freshwater species, which fell by 76 percent over the four decades to 2010, while marine and terrestrial numbers both fell by 39 percent. The main reasons for declining populations were the loss of natural habitats, exploitation through hunting or fishing, and climate change.
To gauge the variations between different countries' environmental impact, the report measured how big an "ecological footprint" each one had and how much productive land and water area, or "biocapacity", each country accounted for.
Kuwaitis had the biggest ecological footprint, meaning they consume and waste more resources per head than any other nation, the report said, followed by Qatar and the United Arab Emirates.
"If all people on the planet had the footprint of the average resident of Qatar, we would need 4.8 planets. If we
lived the lifestyle of a typical resident of the USA, we would need 3.9 planets," the report said.
Many poorer countries - including India, Indonesia and the Democratic Republic of Congo - had an ecological footprint that was well within the planet's ability to absorb their demands.