25 percent of the U.S. population lived in cities, and 75 percent lived in the country or in small towns. Now it is about the reverse—80 percent urban, 20 percent rural. Those statistics should not surprise most people; it’s old news that the world is racing toward urbanization. But it’s worth paying attention to the profound social and ecological implications of that shift.

Think, for instance, about our relationship to nature. What connection can urbanites feel to nature when the only walks they take are on sidewalks?

With the exception of fund raising, most conservationists have ignored cities, and in this regard The Nature Conservancy is typical. It is in our DNA to avoid urban areas; we are staffed with people who love wild and remote places, people who escape cities to hike and camp out. We rely on scientific assessments of habitat to decide where to work and then find that urban sites are too degraded to rise to the top of our priority lists. Our aversion to cities also has deep historical roots: Conservation icons such as John Muir had disdain for the dirty places that cities represented to him. How many nature essays have you read heralding the wonder to be found in a city block?

I say that now is the time for conservationists to evolve and re-examine our neglect of urban areas. Here’s why: Conservation is facing a crisis of irrelevance—it is an enterprise that is not urgent to most people. If conservation is to build the support it needs, it must energize young urban dwellers, who now make up most of the world. The best way to get city people to care about conservation is to do conservation where they live so that nature is seen as relevant and connected to modern life. 

Once you start to think seriously about conservation in cities, it becomes clear there are in fact real opportunities. The most obvious arise from restoring rivers and streams. Restoration can turn a toxic river into a haven for fish and contribute to species protection both up- and downstream. The Three Rivers in Pittsburgh, for example, were once (and not that long ago) so polluted that they were a dead zone; their waters corroded boats and drove people away. Now, after 40 years of cleanup and restoration, fish are abundant, and the riverfront is a draw for wildlife and people.

Other urban conservation efforts could include planting city forests for their air-conditioning effect, since urban heat islands can be cooled as much as 9 degrees by replacing asphalt with trees and other vegetation. For coastal cities, nearshore restoration can build fish habitat, reduce storm surges and enhance the quality of life for people. Estuaries such as the Chesapeake Bay, which were once thought to be irreparably damaged, are beginning to show signs of ecological recovery—even though they are surrounded by cities that are still growing.

Finally, conservation in and near cities makes good economic sense. Traditional calculations of the return on investment for conservation projects looked at bucks and acres. The Conservancy has always gravitated to the expansive forests of western North America because you get more acres or species per dollar there. But how many people have access to those wild lands? Imagine instead a different calculation that tallied up people served per dollar of habitat restoration. For example, spending half a billion dollars for streamside restoration in New York City, where 20 million people benefit, is a pretty good bargain, at $25 per person. It beats spending half a billion dollars to protect a remote area that will be enjoyed by at most a few hundred thousand people.

Increasingly, conservationists around the world are talking about the benefits people derive from nature. As a result, we have begun to measure costs and benefits in people units as well as acres. It is no surprise, then, that conserving nature in cities is looking far more desirable now than it ever has before. And that’s a good thing all the way around.

Shouldn’t we be in the business of bringing nature to people?