Wildlife decline: Why does biodiversity matter anyway?

World Wide Fund for Nature's (WWF) latest assessment of global biodiversity is rife with grim statistics. Between 1970 and 2010, half of all vertebrate species around the globe have sharply declined. In that time, nearly 40 percent of all marine and terrestrial populations have fallen and a staggering 76 percent of freshwater species have been compromised.

But what does this steep decline in biodiversity mean for us?

For one thing, the health of wildlife populations can tell us a lot about the overall health of the globe’s ecosystems, says endangered species biologist Jon Hoekstra who serves as vice president and chief scientist for the WWF's US branch.

“They are the canary in the coal mine,” Dr. Hoekstra says. “One reason we are seeing these big declines is there is less habitat; There is less space and less ecosystem for wildlife to live. That forebodes for how well those natural ecosystems can support human life and economic activity as well.”

Forest ecosystems, for instance, not only house cuddly critters, but also provide shelter, livelihoods, water, fuel, and food for more than 2 billion people. Fisheries support more than 660 million jobs globally and supply 15 percent of the animal protein in our diets, according to the report. Economic losses resulting from continued degradation of the world’s fisheries could top $400 billion by 2050.

Today, nearly one billion people suffer from hunger; 768 million do not have access to safe, clean water. These challenges will only become more pronounced as the world’s human populations continues to swell. The latest predictions suggest that total population could top 11 billion by the end of this century.

In addition to providing humans with sustenance, natural ecosystems perform a host of additional services including including pollination, nutrient cycling and erosion control, the authors of WWF’s latest Living Planet Report write.

“Ecosystems are natural capital and we need to invest in them and not just exploit them and spend them down,” Hoekstra says. “You raise capital in order to invest in the future. We need to be doing the same thing with nature.”

One recent estimate highlighted by the researchers places the economic value of global ecosystem services at $125 trillion per year.

Biodiversity also plays a major role in the planet’s resilience in response to climate change, Hoekstra says.

“Communities and ecosystems that are more divers are more stable and more resilient to change,” Hoekstra explains. “We are going to need a world that’s resilient and there’s great evidence that biodiversity does that.”