Decline of Carnivores in Nature Threatens Ecosystems

What would a world without carnivores be like? It'd be pretty terrifying. Scientists have taken a closer look at the current status of large carnivores and the ecological roles they play in regulating ecosystems worldwide. Their findings show that without these species, these ecosystems would become completely out of balance.

"This important paper explores how carnivores regulate the structure and functioning of ecosystems and what happens when they are lost," said John Robinson, Wildlife Conservation Society Executive Vice President of Conservation and Science, in a news release. "For many people, it will be an eye-opener and hopefully bring about a change in attitudes and a deeper appreciation of these key species. Around the world, WCS continues to work to preserve the ecosystems that are vital to carnivores and to understand the critical benefits they provide to both wildlife and people."

So what did this research find? If carnivores disappeared, then there would be long-lasting impacts. For example, sea otters keep sea urchins in check, which feast on kelp beds. Without them, kelp beds would begin to disappear rapidly. Pumas also mediate the browsing of mule deer. If pumas disappeared, then there would be a corresponding decrease in the reproduction and growth of woody plants.

That's not all that carnivores do, either. They also cull herds of weaker animals. This means that populations can maintain healthy genetics.

"In Badlands National Park, we have observed bison born with deformed hooves or portions of their legs missing," said Joel Berger, one of the researchers, in a news release. "Historically, these bison would have been selected out for predation by wolves, contributing to the overall health of the herd. Today, without wolves, these bison survive and reproduce. This is not the way healthy ecosystems are maintained."

Currently, many of the largest carnivores are listed as threatened on the IUCN Red List and most are still declining in number. This is mostly due to human impacts, which include habitat destruction and degradation, persecution, utilization and depletion of prey.

The findings reveal how crucial it is to learn to co-exist and live with predators. They provide a myriad of benefits to the ecosystems that they inhabit. Because of this, it's necessary to create policies that will help protect these carnivores now and in the future.

The findings are published in the journal Science.