When the husband and I bought wooded acreage in the Virginia mountains 30 years ago, we thought we were part of the Back to the Land movement. Turns out we were also part of an exorbitant growth in exurban land use. Defined as low-density rural development, exurban growth has reversed the previous long-term demographic trend of rural residents moving into cities.
By now, everyone’s heard the joke about how developments are named after the very species they displace: Fox Hills Manor, Black Bear Estates and Wild Cat Hills. It’s not a joke anymore. Around 60 million Americans live in exurbia on roughly a quarter of the U.S. landscape. And not just any landscape: exurban developments target the most scenic natural areas, near protected public lands such as state and national parks and forests. These are often the last refuge of many species of flora and fauna squeezed out of human-dominated landscapes.
Even the 6 million-plus acre Greater Yellowstone Ecosystem out west is losing populations of some species to residential development around its borders. Roads not only kill individual animals, but fragment wildlife populations. Free-roaming pets harass and kill wildlife. Livestock introduce non-native pests and diseases. Lawns and agriculture destroy habitats and pollute with chemicals and gasoline. Night lights disorient and kill migratory wildlife.
Ecologists, who normally study pristine wildernesses instead of human-dominated landscapes, are beginning to worry. “The one process now going on that will take millions of years to correct is the loss of genetic and species diversity. This is the folly our descendants are least likely to forgive us,” said Dr. E.O. Wilson of Harvard University.
Wilson is probably the world’s best-known champion of biodiversity, the environmental buzzword that refers to the totality of different native life forms, or species, that inhabit any given region. To scientists like Wilson, biodiversity is the manual to the earth’s operation, in the form of living processes that sustain us with clean water and air, productive land and oceans.
Five million to 100 million species are estimated to be living today. Less than two million have been identified, and we don’t know how most of those function within ecosystems. Globally, around 50,000 species are known to be threatened, mostly due to habitat destruction by humans.
But who really cares about polar bears, much less the microscopic waterbears that inhabit vanishing wetlands? The loss of species is just one dismaying fact among many. We can no longer see the tip of the iceberg of our environmental crisis – because the iceberg has melted.
Yet losing biodiversity is the worst crisis of all, Wilson said. Extinction removes forever the information encoded in life forms, unraveling the very ecosystems that support us.
It should also invoke a spiritual angst. Life is what distinguishes Earth (so far) in the universe. So biodiversity is arguably the highest achievement of either an incomprehensibly intelligent mind, or an incomprehensibly long and complex evolution. Either way, what’s not to find awesome?
Maybe because of this spiritual dimension, a grass-roots embrace of biodiversity seems to be emerging. Volunteers all over the country, including many in the Chesapeake watershed, are learning how to bioblitz – not a video game where one infects opponents with terrible diseases, but systematic, basic inventories of local native flora and fauna, usually in protected habitats like parks. Thousands more volunteer annually to weed out invasive, nonnative plants like garlic mustard. Others are successfully “daylighting” streams long buried in culverts.
“The general direction is going up the right way,” Wilson said in a recent interview in online Grist magazine. “The only question is how much damage are we going to do to biodiversity before we catch on?”
Although slowed by the recession, exurban growth continues to damage biodiversity as real estate recovers. Fortunately, ecologists are publishing many books describing low-impact development practices that conserve and restore biodiversity in landscapes. Unfortunately, a recent survey showed that most municipal planners aren’t reading them.
The influence of planners on development ordinances is crucial, but several scientific papers suggest that homeowner behavior is an even bigger key to salvaging biodiversity. Lawns are pure ecocide, yet yards are becoming potentially critical pieces in the jigsaw puzzle of habitats capable of sustaining local biodiversity.
Having bioblitzed our own backyard, we are now substantially increasing our tally of birds and butterflies by replacing most of the lawn with native plants and mowing only our travel paths. We talk with neighbors and friends about the advantages of native plants, which include far less need for care and water than exotic species. We are considering how to raise consciousness about biodiversity among our local planners. My transition from aging hippie to exurban cowgirl continues apace.
Chris Bolgiano has written or edited six books, several of which have won literary prizes. Distributed by Bay Journal News Service.