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The rainforests of Southeast Asia, the savanna of Africa and the jungles of India could become 'empty landscapes' as some of the best-loved animals on Earth are driven to extinction, scientists have warned.

Oxford University experts say that rhinoceroses, zebras, camels, elephants and other large herbivores are rapidly dwindling in number.

Their habitats are being torn up as humans expand cities and farmland, the scientists warn.

Oxford University experts say that rhinoceroses, zebras, elephants and other large herbivores are rapidly dwindling in number. Their habitats are being torn up as humans expand cities and farmland, scientists warn

And as the large herbivores suffer, the animals that feed on them – tigers, lions and wolves – will suffer as a result.

Their study, published in the journal Science Advances, focused on 74 large herbivore species, each weighing more than 100kg, and found that 25 now occupied only 19 per cent of their historical ranges.

Professor David Macdonald, director of Oxford University's Wildlife Conservation Research Unit, said: 'The big carnivores, like the charismatic big cats or wolves, face horrendous problems from direct persecution, over-hunting and habitat loss, but our new study adds another nail to their coffin - the empty larder - it's no use having habitat if there's nothing left to eat in it.'

If the trend continues the habitats where such creatures make their home will be transformed into 'empty landscapes', as the knock-on effects impact both on predators and plant life, a study suggests.

Study leader Professor William Ripple, of Oregon State University in the US, said: 'I expected that habitat change would be the main factor causing the endangerment of large herbivores.

'But surprisingly, the results show that the two main factors in herbivore declines are hunting by humans and habitat change. They are twin threats.

'Our analysis shows that it goes well beyond forest landscapes, to savannahs and grasslands and deserts. So we coin a new term, the 'empty landscape'.'

The scientists wrote: 'Without radical intervention, large herbivores (and many smaller ones) will continue to disappear from numerous regions with enormous ecological, social and economic costs.'

They pointed out that competition from livestock production, which has tripled globally since 1980, had reduced herbivore access to land, forage and water and raised the risk of disease transmission.

And as the large herbivores suffer (elephant pictured), the animals that feed on them - tigers, lions and wolves – will suffer as a result. The study focused on 74 large herbivore species, each weighing more than 220lbs (100kg), and found that 25 now occupied only 19 per cent of their historical ranges

Hunting for meat consumption and the global trade in animal parts had also taken a heavy toll.

Africa's western black rhinoceros was declared extinct in 2011 as the value of rhino horn soared.

'Horn sells for more by weight than gold, diamonds or cocaine,' said Prof Ripple.

Herbivore loss was likely to rob carnivores such as lions and tigers of food, diminish seed dispersal, slow the cycle of nutrients from vegetation to the soil, and alter the habitats of smaller animals including fish, birds and amphibians.

Herbivore loss was likely to rob carnivores (jaguar pictured) of food, diminish seed dispersal, slow the cycle of nutrients from vegetation to the soil, and alter habitats of smaller animals including fish, birds and amphibians

In a separate study from the University of Berkeley in California, scientists recently examined extinction rates in fossils over 23 million years. They found that the tropics and Antarctica are most at risk and animals such as whales and dolphins are especially vulnerable

With fewer large herbivores clearing vegetation and creating natural fire breaks, wildfires were likely to become more frequent and intense.

As a group, terrestrial herbivores include around 4,000 known species and occupy many types of ecosystem on every continent except Antarctica.

The majority of threatened large herbivores lived in developing countries, particularly Africa, India and South-East Asia, said the researchers.

Professor Ripple said: 'We hope this report increases appreciation for the importance of large herbivores in these ecosystems. And we hope that policy makers take action to conserve these species.