Global animal populations decreased by 50 percent over the last 40 years, reports the World Wide Fund for Nature (wwf) and the Zoological Society of London (zsl). Scientists found that animals are hunted at unsustainable numbers, while land and aquatic creatures are being decimated as man pollutes and destroys natural habitats, the Guardian reported September 29.

“If half the animals died in London zoo next week it would be front page news,” Prof. Ken Norris, zsl’s director of science, said. “But that is happening in the great outdoors. This damage is not inevitable but a consequence of the way we choose to live.”

Man’s lifestyle is destroying nature at an unsustainable rate. Consequently, the food chain, which includes the supply of clean water and air, is under severe stress. Unless reversed, man’s mismanagement and abuse of the Earth could lead to nation’s battling for the last available resources.

“We have lost one half of the animal population and knowing this is driven by human consumption, this is clearly a call to arms and we must act now,” Mike Barratt, director of science and policy at wwf, said.

The freshwater ecosystem faces the sharpest decline in population: Populations have plummeted 75 percent since 1970. Man’s poor agricultural practices directly affect this ecosystem. “Whatever happens on the land, it all ends up in the rivers,” wwf chief freshwater adviser Dave Tickner said.

The Aral Sea—the world’s fourth-largest lake—is becoming a desert, testament to man’s mismanagement of our resources. At its peak the Aral Sea had a fishing industry that employed 60,000 people. Rusty beached boats and camels now its main inhabitants.

Terrestrial populations have fallen by 40 percent in the last 40 years. Habitat destruction and poaching factor largely in this decline. Over 1 million elephants roamed Africa and Southern Asia in 1977, but due to high demand for ivory, their numbers have fallen 50 percent, down to 600,000.

Marine wildlife is under threat as well. Marine populations were reduced by 40 percent overall. Turtle numbers have decreased by 80 percent due to loss of habitat, hunting and getting caught in fishing nets. Overfishing is also taking its toll. The Atlantic bluefin tuna has declined to the point where its survival as a species is seriously endangered.

The annihilation of forests and wildlife populations is not new. Man has been destroying his environment for centuries. Modern technology has allowed him to destroy it faster than ever before.

Man’s greed has led him to practice many unsustainable patterns. Although there is nothing wrong with hunting animals for food or clearing forest for cropland or living space, it’s the rate at which it is done and how it is done that is causing the problems.

Read “The Sea That Became a Desert” for the solution to man’s unsustainable practices.