A majority now occupy less than half their former ranges according to data published in the journal, Science.
The loss of this habitat and prey and persecution by humans has created global hotspots of decline.
The researchers say the loss of these species could be extremely damaging for ecosystems the world over.
The authors say that in the developed world, most carnivorous animals have already succumbed to extinction.
When they looked at 31 big meat eaters, they found that they were under increasing pressure in the Amazon, South East Asia, southern and East Africa.
"Globally, we are losing our large carnivores," said lead author Prof William Ripple from Oregon State University.
"Their ranges are collapsing. Many of these animals are at risk of extinction, either locally or globally."http://www.bbc.co.uk/news/science-environment-25675002
n more than half of European countries, there are not enough honeybees to pollinate crops, according to new research.
