The amount of wildlife in the world’s forests has plummeted by more than half (53 per cent) in just over 40 years, conservationists have found.

Humanity is killing the Earth’s greatest natural ally in the fight against climate breakdown, our forests, according to the report by the WWF.

The charity is calling on world leaders to declare a planetary emergency and develop a “new deal for nature and people” to halt climate breakdown, restore nature and fix food systems.

The first ever global assessment of forest biodiversity shows that habitat loss and degradation, chiefly caused by people, account for 60 per cent of the threats to forests and forest species.

The report, ‘Below the Canopy’, written jointly by WWF and ZSL, found the drops in wild animal and bird populations were greatest in tropical forests such as the Amazon rainforest, where there is the most wildlife to lose.

World's most endangered animals Show all 17 1 /17 World's most endangered animals World's most endangered animals Amur Leopard Endemic to the far east of Russia, the Amur Leopard has a population of around 84 and is critically endangered. Here follows every species that the WWF lists as critically endangered. Getty World's most endangered animals Sumatran Elephant The Sumatran elephant population now stands at only 2400-2800 Getty World's most endangered animals Yangtze Finless Porpoise Endemic to China's Yangtze River, the Yangtze finless porpoise has an estimated population of 1000-1800 Kenichi Nobusue World's most endangered animals South China Tiger When discovered in the 1950s, the South China tiger population was estimated to be 4000, by 1996 it was estimated to be only 30-80. Scientists consider the tiger to be "functionally extinct" as one has not been sighted for over 25 years World's most endangered animals Sumatran Orangutan The Sumatran orangutan was once found across the island of Sumatra and even further south on Java. Today it is found only in the island's north and its population stands at 14,613 Getty World's most endangered animals Western Lowland Gorilla Though it is the most populous of all gorilla subspecies, the western lowland gorilla is still critically endangered and its population has declined by 60% in the last quarter century Getty World's most endangered animals Sumatran Rhinoceros The Sumatran rhinoceros is the smallest of the surviving rhinoceros species. Only 80 are known to be living today. The last male Sumatran rhino in Malaysia died on 28 May 2019 Willem V Strien World's most endangered animals Sumatran Tiger There are fewer than 400 Sumatran tigers left today. They are severely threatened by deforestation and poaching Getty World's most endangered animals Eastern Lowland Gorilla Half of the rainforest of the Democratic Republic of Congo in which these gorillas live has been destroyed the past 50 years. There were 17,000 Eastern Lowland gorillas in the 1990s but scientists estimate their population has declined by over 50% since then Getty World's most endangered animals Vaquita The world's rarest marine animal has a population of only 30. They were discovered in 1958 and are endemic to Mexico's Gulf of California Paula Olson / NOAA World's most endangered animals Javan Rhino The most threatened of all rhino species, there are only an estimated 58-68 Javan rhinos left Reuters World's most endangered animals Saola The saola was first sighted in 1992, being the first large mammal to be discovered in over 50 years. Scientists have only sighted saola in the wild four times and it is considered critically endangered World's most endangered animals Malayan Tiger The Malayan Tiger population now stands at only 250-300 Getty World's most endangered animals Hawksbill Turtle The population of the Hawksbill Turtle has declined by more than 80% in the last century. They are threatened by black market poachers who kill them for their shell Getty World's most endangered animals Black Rhino The population of the black rhino dropped by 98% in the years 1960-1995 due to poaching, it stands today at around 5000 Getty World's most endangered animals Cross River Gorilla The population of the Cross River gorilla has been damaged by deforestation and poaching, it now stands at 200-300 Julie Langford World's most endangered animals Bornean Orangutan The population of the Bornean orangutan has been reduced by over 50% in the past 60 years, now standing at around 104,700. Their habitat has been reduced by at least 50% in the 21st century Getty

Monitored populations of forest-living birds, mammals, amphibians and reptiles declined, on average, by 53 per cent between 1970 and 2014, the most recent year with available data.

Protecting and restoring forests must be at the heart of the global plan, the charity says.

WWF says that forests, which are home to more than half of the world’s land-based species, are vital to the health of the planet, absorbing damaging greenhouse gases.

The report outlines how in the vast tropical forests of South America and Africa, the carbon locked in would decline if large birds and primates in particular were lost.

“When animals are lost from forests this has severe implications for forest health, the livelihoods of more than a billion humans who depend on forests, and our opportunity to mitigate against climate disaster,” WWF says.

Deforestation and forest degradation account for about 10 per cent of global greenhouse gas emissions.

Some scientists argue that an irreversible transformation of the Amazon is close as already about a fifth has been cleared, close to the tipping point of 20-25 per cent, where some rainforest could dry out into a savannah.

The report authors want heads of state to develop a new global agreement at the 75th UN General Assembly meeting next year, when they are expected to negotiate new 10-year targets for the Convention on Biological Diversity.

Will Baldwin-Cantello, a WWF forests specialist, said: “Forests are complex systems that depend on the wildlife that live in them to keep them healthy, and the rapid decrease in forest wildlife in recent decades is an urgent warning sign.

“Forests are our greatest natural ally in the fight against climate breakdown. We lose them at our peril.

“We need global leaders to declare a planetary emergency and kickstart a global programme of recovery to keep our forests standing to protect our planet.”