About an hour north of Bejing, not far from the 6th Ring Road, lies a 143-unit housing development. Viewed one way, it is a place no different from so many others nearby; just one small example of the ongoing transformation of China.
But this decade-old development has also turned out to be something of a harbinger: The housing stock consists entirely of single-family homes, most of which appear to have been airlifted in directly from Southern California. The “Orange County” gated community was designed to tap into the desires of a growing number of Chinese who can afford to pursue what is rapidly becoming a global dream — to live in the suburbs.
In developing economies around the world, residential environments utterly familiar to suburban Americans are appearing at an ever-increasing pace. Many of the same drivers that led to the explosion of suburban development in the United States after World War II are operating in these places now as well: Higher incomes and improved mobility are allowing people to live in ways that were, until very recently, impossible. When the Orange County development opened just 10 years ago, there were only 3 cars per 100 households in Beijing. The rate of private vehicle ownership in the city is now over 30 cars per 100 households. During the same period, China has added more than 70,000 km to its expressway network — which is now the longest in the world.
As well, some familiar disincentives are coming into play to fuel suburban growth: cities in high-growth developing countries are being increasingly perceived as dirty and dangerous environments. This is not just a Chinese phenomenon. In economies around the world where a prosperous middle class is emerging, there are signs of suburbanization appearing as well. As the red hot IT industry developed in Bangalore, India, the population skyrocketed by more than 3 million in the last decade. Those good paying jobs are fueling demand for residences in gated communities on Bangalore’s fringe.
And the numbers of people involved in this dynamic in countries all around the world will mean an enormous shift in the ways that the global human population will interact with and influence the planet.
As conservation scientists in the most suburban nation on Earth, what have we in the United States learned that may be useful to other countries as they undergo their own metamorphoses? Unfortunately, the conservation science of suburbia can mostly be boiled down to a distinct aversion. One study after another has chronicled issues associated with suburbia such as habitat loss, fragmentation and isolation of remaining ecosystem relicts; associated extinctions of native species; and introduction of exotic species. The litany of documented impacts has been reproduced in wet forests, shrublands and deserts.
The net result of this work is that we know very well the variety of harms suburbia inflicts on nature. And the conclusion of the scientific community with respect to suburbanization has largely been: don’t do it. But there is scant evidence that this message has been heeded in North America, and there is even less reason to expect that it will be heard on other continents by people who are strongly motivated to leave other modes of living behind them.
“The conclusion of the scientific community with respect to suburbanization has largely been: don’t do it. But there is scant evidence that this message has been heeded in North America, and there is even less reason to expect that it will be heard on other continents.” – David Skelly
We need the conservation science community to join a different conversation — one in which we can be heard. Once we recognize that suburbs will become an even more pervasive — even global — phenomenon during the 21st century, what advice can we offer? We can restate this question a different way: how can suburban development be carried out in a way that meets people’s needs and desires while also fostering positive conservation outcomes? Even further: Can thinking about natural environments make suburbs better for people as well?
Answering these questions will take a different kind of science. Most prior studies have compared a reference — undeveloped landscape — with a developed landscape, yielding what is most often a predictable outcome. What we really need is a more nuanced understanding of pattern and process in these systems.
For instance: Most species do not simply drop dead when they get near a housing development. James Gibbs (1998) collected some compelling data on the ways in which different species of amphibians differentially infiltrate suburban environments (Fig. 1). Most species eventually disappear as development becomes more intensified. But their thresholds differ — and in each case, a decay in occupancy is evident. We need to know much more about that decay. What causes it, and why do species and the ecosystems that support them tend to persist in some suburban contexts and not others?
My lab at Yale carried out an experiment this summer as a first step toward answering such questions for the system I work in. We asked whether the quality of available breeding ponds contributes to the decay of species occupancy in suburban environments. We worked in a dozen Connecticut ponds located on either side of the suburban range edge of the wood frog. This species is present in rural and low-density suburban neighborhoods and largely absent from higher density suburbs. We placed hatchling larvae in enclosures, then waited until they were reaching metamorphosis to recover the survivors. The upshot of the study: larvae placed in the extralimital ponds (those outside the wood frog’s range) performed as well or better than those within the range.
This result is striking. The little ponds next to school bus parking lots, the ones behind someone’s yard and the other ones behind the grocery store all did just as good a job at supporting recruitment of wood frogs as did beautiful vernal ponds on land-trust properties and those within other extensive tracts of native vegetation. These findings are putting us on a path to considering the ways in which the terrestrial environment may alternately support or challenge wildlife like wood frogs.
We want to get beyond the development = bad mindset to discover exactly what species such as amphibians require to make it in the same landscapes where people live. As comparable work on other taxa and systems accumulates, we will be on our way to developing precepts for suburban environments that can support native species and foster ecosystem processes that are usually lost under the current development practices.
“We want to get beyond the development = bad mindset to discover exactly what species require to make it in the same landscapes where people live.” – David Skelly
Suburbs are inherently aspirational. People who choose to live somewhere that is neither urban nor rural are making a statement about their priorities and their values. We know that proximity to nature is often cited as a reason that people choose to live in the suburbs. But we need to know more about the value people place on authentic natural systems with intact ecosystem processes supporting clean air and clean water. The massive experiments in suburbanization ongoing within China and elsewhere offer unprecedented opportunities to develop new models. We will know these models have been successful when southern Californians turn to Chinese examples for the next generation of American suburbs.
Gibbs, J. P. 1998. Distribution of woodland amphibians along a forest fragmentation gradient. Landscape Ecology 13:263-268.
September 24, 2013. The views expressed above are the author’s and should not be taken as those of SNAP or its member organizations.