Stockbyte/Thinkstock(NEW YORK) — The global population of wildlife has declined drastically since 1970, suffering a drop of 58 percent between 1970 and 2012, according to a new report from the World Wildlife Fund (WWF) and the Zoological Society of London.

The overall number of vertebrates — a group that includes mammals, birds, reptiles, amphibians and fish — has dropped dramatically as a result of human activity, the conservation groups say, with animals living in the freshwater systems showing the greatest decline, at 81 percent. The groups’ bi-annual Living Planet report found that wildlife in the world’s oceans dropped by 36 percent while on land the population numbers fell by 38 percent.

If current trends continue, the groups say, more than two-thirds of all global wildlife will be in decline by 2020.

“For the first time since the demise of the dinosaurs 65 million years ago, we face a global mass extinction of wildlife,” said Mike Barrett, director of science and policy at WWF-UK.

The study blames human activities including deforestation, pollution, overfishing and the illegal wildlife trade as well as climate change for pushing species to the edge. The biggest culprit, according to the WWF, is habitat loss and degradation caused mainly by the global food system.

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