London: Animals like tigers and polar bears are much more vulnerable to environmental change because of their huge appetite, researchers say.
Large predators suffer more than smaller species from habitat change because they have to work harder to find their next meal.
Experts found numbers of mammals like lions, tigers and polar bears dropped more, compared to weasels or badgers, when food was scarce, according to the journal Biology Letters.
It suggests that the vulnerability of larger species may be linked with the high energetic costs of being `big`, reports the Daily Mail.
The robustness and large size of these species, which are well suited for hunting large prey, might become a hindrance when times are tough.
Phillip Stephens, from Durham University`s School of Biological and Biomedical Sciences, in UK, said that when prey was scarce, large predator populations dropped five to six times more than those of their smaller rivals.
He said: "It`s hard work being a large predator roaming and hunting across extensive areas to find food."
"The apparent vulnerability of tigers and polar bears to reductions in the availability of prey may be linked to the energetic costs of being a large carnivore."