Humanity has wiped out 60% of mammals, birds, fish and reptiles since 1970, leading the world’s foremost experts to warn that the annihilation of wildlife is now an emergency that threatens civilisation. The new estimate of the massacre of wildlife is made in a major report produced by WWF and involving 59 scientists from across the globe. It finds that the vast and growing consumption of food and resources by the global population is destroying the web of life, billions of years in the making, upon which human society ultimately depends for clean air, water and everything else. “We are sleepwalking towards the edge of a cliff” said Mike Barrett, executive director of science and conservation at WWF. “If there was a 60% decline in the human population, that would be equivalent to emptying North America, South America, Africa, Europe, China and Oceania. That is the scale of what we have done.” “This is far more than just being about losing the wonders of nature, desperately sad though that is,” he said. “This is actually now jeopardising the future of people. Nature is not a ‘nice to have’ – it is our life-support system.” interactive“We are rapidly running out of time,” said Prof Johan Rockström, a global sustainability expert at the Potsdam Institute for Climate Impact Research in Germany. “Only by addressing both ecosystems and climate do we stand a chance of safeguarding a stable planet for humanity’s future on Earth.” Many scientists believe the world has begun a sixth mass extinction, the first to be caused by a species – Homo sapiens. Other recent analyses have revealed that humankind has destroyed 83% of all mammals and half of plants since the dawn of civilisation and that, even if the destruction were to end now, it would take 5-7 million years for the natural world to recover. The Living Planet Index, produced for WWF by the Zoological Society of London, uses data on 16,704 populations of mammals, birds, fish, reptiles and amphibians, representing more than 4,000 species, to track the decline of wildlife. Between 1970 and 2014, the latest data available, populations fell by an average of 60%. Four years ago, the decline was 52%. The “shocking truth”, said Barrett, is that the wildlife crash is continuing unabated. Wildlife and the ecosystems are vital to human life, said Prof Bob Watson, one of the world’s most eminent environmental scientists and currently chair of an intergovernmental panel on biodiversity that said in March that the destruction of nature is as dangerous as climate change. “Nature contributes to human wellbeing culturally and spiritually, as well as through the critical production of food, clean water, and energy, and through regulating the Earth’s climate, pollution, pollination and floods,” he said. “The Living Planet report clearly demonstrates that human activities are destroying nature at an unacceptable rate, threatening the wellbeing of current and future generations.” The biggest cause of wildlife losses is the destruction of natural habitats, much of it to create farmland. Three-quarters of all land on Earth is now significantly affected by human activities. Killing for food is the next biggest cause – 300 mammal species are being eaten into extinction – while the oceans are massively overfished, with more than half now being industrially fished. African elephants: With 55 being poached for ivory every day, more are being poached than are being born, meaning populations are plunging Orangutans: More than 100,000 were lost in Borneo alone between 1999 and 2015, largely due to forest destruction for timber and palm oil, leaving the great apes critically endangered Whale sharks: Numbers of the largest fish have collapsed by two thirds in the last 75 years in the Indian and-Pacific Oceans, due to overfishing and ship collisions. Wandering albatross: Populations are declining rapidly, driven largely by accidental catches in long line fisheries. One monitored population on South Georgia fell by half between 1972 and 2010 Jaguar: The razing of forests in South America is driving the decline of this big cat, which prefers to live in dense jungle Gharials: There are now just 200 breeding adults of the fish-eating crocodile in the wild in India and Nepal, the result of rampant fishing, poaching and drops in river flow. Chinese giant salamander: This creature is one of 545 critically endangered amphibians, decimated by hunting for food, destruction of rivers and lakes and pollution. Hedgehog: This animal is among the fifth of UK mammals at high risk of extinction, with populations having fallen hugely in both urban and rural locations. Thank you for your feedback. Chemical pollution is also significant: half the world’s killer whale populations are now doomed to die from PCB contamination. Global trade introduces invasive species and disease, with amphibians decimated by a fungal disease thought to be spread by the pet trade. Lange's metalmark butterfly from Amy Harwood. The first wave of extinctions targeted large vertebrates hunted by hunter-gatherers. The second, larger wave began 10,000 years ago as the discovery of agriculture caused a population boom and a need to plow wildlife habitats, divert streams, and maintain large herds of domestic cattle. The third and largest wave began in 1800 with the harnessing of fossil fuels. With enormous, cheap energy at its disposal, the human population grew rapidly from 1 billion in 1800 to 2 billion in 1930, 4 billion in 1975, and over 7.5 billion today. If the current course is not altered, we’ll reach 8 billion by 2020 and 9 to 15 billion (likely the former) by 2050. No population of a large vertebrate animal in the history of the planet has grown that much, that fast, or with such devastating consequences to its fellow earthlings. Humans’ impact has been so profound that scientists have proposed that the Holocene era be declared over and the current epoch (beginning in about 1900) be called the Anthropocene: the age when the "global environmental effects of increased human population and economic development" dominate planetary physical, chemical, and biological conditions [2].
 The authors of Human Domination of Earth's Ecosystems, including the current director of the National Oceanic and Atmospheric Administration, concluded:
Predicting local extinction rates is complex due to differences in biological diversity, species distribution, climate, vegetation, habitat threats, invasive species, consumption patterns, and enacted conservation measures. One constant, however, is human population pressure. A study of 114 nations found that human population density predicted with 88-percent accuracy the number of endangered birds and mammals as identified by the International Union for the Conservation of Nature [4]. Current population growth trends indicate that the number of threatened species will increase by 7 percent over the next 20 years and 14 percent by 2050. And that’s without the addition of global warming impacts. When the population of a species grows beyond the capacity of its environment to sustain it, it reduces that capacity below the original level, ensuring an eventual population crash. "The density of people is a key factor in species threats," said Jeffrey McKee, one of the study’s authors. "If other species follow the same pattern as the mammals and birds... we are facing a serious threat to global biodiversity associated with our growing human population." [5]. So where does wildlife stand today in relation to 7.5 billion people? Worldwide, 12 percent of mammals, 12 percent of birds, 31 percent of reptiles, 30 percent of amphibians, and 37 percent of fish are threatened with extinction [6]. Not enough plants and invertebrates have been assessed to determine their global threat level, but it is severe. Extinction is the most serious, utterly irreversible effect of unsustainable human population. But unfortunately, many analyses of what a sustainable human population level would look like presume that the goal is simply to keep the human race at a level where it has enough food and clean water to survive. Our notion of sustainability and ecological footprint — indeed, our notion of world worth living in — presumes that humans will allow for, and themselves enjoy, enough room and resources for all species to live. REFERENCES CITED
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What would happen in an ecosystem if the population of 1 animal increased or decreased significantly?
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