Science and Health

The World Is Losing Its Biggest Carnivores: Study

A new study from Oregon State finds the majority of the world's largest carnivores have seen a population drop.

The World Is Losing Its Biggest Carnivores: Study
Flickr / Gerard van Drunen

Most of the world's major carnivores like leopards, lions and cheetahs are on the decline — and scientists say that drop could hurt the environment.

That's according to a new study out of Oregon State University. It says almost 75 percent of the world's 31 largest carnivores have been experiencing a population drop — and there are at least a couple reasons behind it. (Via Wikimedia Commons / Seney Natural History Association)

One of the reasons is climate change. In some cases, it's causing animals to hunt for different types of foods that don't carry the same nutritional benefit they need.

For example, the study found polar bears have had a tough time hunting seals because there's less ice on the shore than normal — meaning they've had to resort to eating bird eggs to keep from starving. (Via Los Angeles Times)

And NBC notes if animal populations rose, it could end up reversing the trend. " ... regions where carnivores keep other animal populations in check are full of plants that soak up carbon from the atmosphere, helping to slow global climate change."

But The Christian Science Monitor notes humans are also playing a role in the population drop. Livestock demand tripled between 1980 and 2002, which meant farmers had to keep taking up more land.

Wolves and other carnivores populated much of that land which meant they had a smaller habitat. And when those animals tried hunting new livestock, farmers would poison the carnivores by putting neurotoxins on its prey or call for the Department of Agriculture to even shoot them down.

But it's not all bad news. Voice of America points out places like Yellowstone National Park, which reintroduced wolves in the 1990s, have been able to improve their ecosystem.

The scientists say they remain hopeful that there is a way to turn the population drop around, but it won't be easy.

The study's overview in the journal Science says: "Preventing the extinction of these species and the loss of their irreplaceable ecological function and importance will require novel, bold, and deliberate actions."

The researchers pointed to wildlife laws in countries like China and India as successful models for conservation.