Mixing Ecology Into Economics

In Bristol Bay, Alaska, fishermen catch and export about 70 percent of the wild salmon in the bay migrating inland to spawn. In recent years, the numbers of salmon that migrate into these Alaskan waters have remained stable. So, that must mean fishermen are harvesting this food resource sustainably, right?

Sockeye Salmon spawning (Wikimedia Commons)

Not necessarily, writes Joseph Burger, Jim Brown and others from the University of New Mexico in an essay published  today in PLoS Biology. The fishery still affects the greater ecosystem. For example, the authors point out, fewer salmon in Alaska’s waters means less food for natural predators such as grizzly bears and bald eagles.  Also, fewer salmon will die naturally in these waters, robbing the soil and waters of other nutrients the rest of the ecosystem depends on. So, while the commercial harvest of salmon may be sustainable from year to year, the fishery still has many indirect impacts on other resources.

It may seem obvious that ecologists have a vital role to play in building a sustainable globe. But as Burger and other scientists argue in several papers contained in the new PLoS Biology Sustainability Collection, ecology, especially the large-scale approach called “macroecology,” has played a smaller role than economics in building a vision of a viable “green economy.” They are calling for the inclusion of ecological principles in discussions on sustainability science both throughout the field and at this week’s Rio+20 sustainability conference.

Rio+20 is a global conference in Rio de Janeiro in which scientists and government representatives from throughout the world discuss how to create a world in which resources can continuously support future generations, while helping people in developing countries rise out of poverty. The first conference was held 20 years ago, and this week’s conference will be a discussion of both the progress made since and what steps come next.

The key, says Burger, is to get economists to think in terms of physics and ecology as well as economics. That means adding more natural sciences to the education economists receive as well as bringing more natural scientists, such as ecologists, into discussions on sustainability. “One could go through an entire bachelor’s or even Ph.D. program in economics and not have any exposure to basic principles like the physical laws of thermodynamics,” he says, “or the biological laws of population growth.”

John Matthews and Frederick Boltz of Conservation International say in their perspective piece that ignoring the dynamic nature of biology is dangerous and will hinder sustainability efforts. But they add that there is room for “cautious optimism.” Matthews and Boltz say scientists can draw from recent efforts to curb climate change for inspiration on how advancing technology can help create a more sustainable world.  “Many developing countries understand that Western models of development are inappropriate if not impossible to achieve. We believe that these and other positive trends are both accelerating and permeating local, national, and global economies quickly and permanently,” they write.

Sustainability must be viewed in the context of the environmental sciences, says population biologist Georgina Mace of Imperial College London. She says that the perspectives offered by Burger and colleagues and Matthews and Boltz represent two extremes of “ecological pessimism” and “technological optimism.” But these extremes are sometimes needed, especially regarding resources that may run out entirely.  “When resources are close to being depleted or exhausted, prices rise, pressures may increase, and complete collapse of the resource becomes more likely,” she writes. “In some other cases, such as the extinction of species or the loss of biomes and biodiversity, the loss is irreversible.”

These scientists argue that the current model for creating a sustainable Earth is too short-sighted, and overly focused on balancing specific sectors of economies while ignoring the intricate web of subtle effects that environmental scientists specialize in puzzling out.

Burger says the ultimate goal however is to get policymakers and environmental scientists working with a mutual framework, and he believes the best way to begin is by increasing education between fields. “We must get everyone on the same page,” says Burger.  “Policymakers and economists have much to benefit from understanding the ecology of our own species and we need them to make our science actionable by implementing policy that considers the core ecological principles that govern all life.”