Oysters help people. Besides the obvious benefits as a food source, healthy oyster reefs provide the critical service of reducing wave size and corresponding storm surges along temperate coasts around the world. Even so, more than 85 percent of oyster reefs have disappeared worldwide due to overharvesting, dredging, pollution, and disease. Oyster populations in the Gulf of Mexico, for example, have suffered a full century of decline. Native oyster beds there received sparse attention and few protections — until Hurricane Katrina, that is. Then suddenly policy makers and members of the public were clamoring to know more about what the oyster ecosystem was worth.
Photo by USWFS
Artificial oyster reefs parallel to the shoreline is a natural way to slow the rate of erosion by catching the wave energy.
“No conservation work gets done without humans valuing nature," says Peter Kareiva, lead scientist for The Nature Conservancy. Clean water to drink, consistent wood supplies for construction, healthy root mass to hold precious soils in place — humans critically depend on all sorts of functioning ecosystems. But historically we haven't had the tools to quantify that dependency.
Cue the Natural Capital Project, or Nat Cap, as it is sometimes called. Founded in 2006 and supported jointly by The Nature Conservancy, The World Wildlife Fund, Stanford University, and the University of Minnesota, Nat Cap tries to provide decision-makers with a framework that captures and quantifies all the ways ecosystems and biodiversity yield benefits to humanity.
"It's easy to talk about the various services provided by ecosystems," says Gretchen Daily, Professor of biology at Stanford and cofounder of Nat Cap. "The hard part," Daily says, "is creating tools to quantify those services." The main tool offered by Nat Cap is InVEST, open-source modeling software that quantifies ecosystem services and predicts the changes to those services based on changes due to decisions or climate change.
NatCap has taught governments, corporations, and other stakeholders around the globe how to use InVEST to assign meaningful value to the resources that had been previously left off the ledger. Mary Ruckleshaus, managing director of Nat Cap, says that the demand for Nat Cap's assistance is exploding, with 500 downloads of the InVEST suite every month. The organization attempts to assist every group who is using their software, although it targets its resources on the major decision-making processes occurring at regional and national scales.
In the Gulf of Mexico, the Nature Conservancy used InVEST to map out various possible post-Katrina oyster restoration scenarios and corresponding ecosystem service benefits. Nat Cap then helped the Nature Conservancy and state and federal agencies prioritize the areas that would protect coastal settlements and fishing economies.
Monetizing beneficial services is just one aspect of the InVEST tools. "Gulf Coast decision-makers didn't want to know about dollar amounts," Ruckleshaus says. "Instead, they wanted to know who and where the winners and losers would be."
"If we had been managing exclusively for biodiversity," Kareiva says about the Gulf oyster restoration, "then we would not have built the reefs where we did."
Thanks to its people-oriented approach, the restoration effort received huge support from the federal government. Within months after Deepwater Horizon, President Obama ordered the creation of the Gulf Coast Ecosystem Task Force. Even the ineffectual 112th Congress passed the RESTORE Act, which created the Gulf Coast Restoration Fund and funneled 80 percent of all Clean Water Act fines collected from BP and other parties implicated in the Deepwater Horizon spill.
Some environmentalists have expressed worries that by trying to put a price tag on ecosystems, we might end up undermining their intrinsic value. "When you are talking about watersheds or other ecosystems, they can look healthy, but what has really happened to species diversity?" asks Michael Soulé, professor emeritus at UC-Santa Cruz. Soulé was instrumental in the development of the modern field of conservation biology. One of his fears is that natural capital is a politically palatable way for governments and corporations to provide for their own interests while doing little to stem the global loss of biodiversity.
In response, boosters of ecosystem services say we need a variety of techniques to promote conservation. "There is no silver bullet," Daily says. "There are very different cultural and economic realities all around the world, and so there need to be very different strategies."
Daily points to China as an exciting example: The Chinese government has spent the last five years mapping out a new system of reserves that will preserve 24 percent of its land area in the form of Ecosystem Function Conservation Areas. This huge conservation effort, which includes a National Ecosystem Services Assessment every decade, is meant to sustain arable soils, secure clean and abundant water, mitigate severe flooding, and reverse desertification. At its center, the program is designed to sustain biodiversity across the nation, which hosts 10 percent of the world's animal and plant species.
Humans have always benefitted from nature's living systems. Now, Nat Cap is asking people to pay for them. Will other decision-makers follow China's lead and pay for services that were previously considered free of charge? Gretchen Daily thinks so. "Now our big challenge," Daily says, "is ensuring a return investment. These projects will have to yield quantity and quality."
Let’s hope so — for biodiversity’s sake as well as for our own.