By HUGH RAFFLES
The New York Times
April 2, 2011
THE anti-immigrant sentiment sweeping the country, from draconian laws in Arizona to armed militias along the Mexican border, has taken many Americans by surprise. It shouldn’t — nativism runs deep in the United States. Just ask our non-native animals and plants: they too are commonly labeled as aliens, even though they also provide significant benefits to their new home.
While the vanguard of the anti-immigrant crusade is found among the likes of the Minutemen and the Tea Party, the native species movement is led by environmentalists, conservationists and gardeners. Despite cultural and political differences, both are motivated — in Margaret Thatcher’s infamous phrase — by the fear of being swamped by aliens.
But just as America is a nation built by waves of immigrants, our natural landscape is a shifting mosaic of plant and animal life. Like humans, plants and animals travel, often in ways beyond our knowledge and control. They arrive unannounced, encounter unfamiliar conditions and proceed to remake each other and their surroundings.
Designating some as native and others as alien denies this ecological and genetic dynamism. It draws an arbitrary historical line based as much on aesthetics, morality and politics as on science, a line that creates a mythic time of purity before places were polluted by interlopers.
What’s more, many of the species we now think of as natives may not be especially well suited to being here. They might be, in an ecological sense, temporary residents, no matter how permanent they seem to us.
These “native” species can have serious effects on their environment. Take the mountain pine beetle: thanks to climate change, its population is exploding in the West, devastating hundreds of thousands of square miles of forest.
It’s true that some non-native species have brought with them expensive and well-publicized problems; zebra mussels, nutria and kudzu are prime examples. But even these notorious villains have ecological or economic benefits. Zebra mussels, for example, significantly improve water quality, which increases populations of small fish, invertebrates and seaweeds — and that, in turn, has helped expand the number of larger fish and birds.
Indeed, non-native plants and animals have transformed the American landscape in unmistakably positive ways. Honeybees were introduced from Europe in the 1600s, and new stocks from elsewhere in the world have landed at least eight times since. They succeeded in making themselves indispensable, economically and symbolically. In the process, they made us grateful that they arrived, stayed and found their place.
But the honeybee is a lucky exception. Today, a species’s immigration status often makes it a target for eradication, no matter its effect on the environment. Eucalyptus trees, charged with everything from suffocating birds with their resin to elevating fire risk with their peeling bark, are the targets of large-scale felling.
Yet eucalyptuses are not only majestic trees popular with picnickers, they are one of the few sources of nectar available to northern Californian bees in winter and a vital destination for migrating monarch butterflies.
Or take ice plant, a much-vilified Old World succulent that spreads its thick, candy-colored carpet along the California coast. Concerned that it is crowding out native wildflowers, legions of environmental volunteers rip it from the sandy soil and pile it in slowly moldering heaps along the cliffs.
Yet ice plant, introduced to the West Coast at the beginning of the 20th century to stabilize railroad tracks, is an attractive plant that can also deter erosion of the sandstone bluffs on which it grows.
There are plenty of less controversial examples. Non-native shad, crayfish and mud snails provide food for salmon and other fish. Non-native oysters on the Pacific Coast build reefs that create habitat for crab, mussels and small fish, appearing to increase these animals’ populations.
And in any case, efforts to restore ecosystems to an imagined pristine state almost always fail: once a species begins to thrive in a new environment, there’s little we can do to stop it. Indeed, these efforts are often expensive and can increase rather than relieve environmental harm.
An alternative is to embrace the impurity of our cosmopolitan natural world and, as some biologists are now arguing, to consider the many ways that non-native plants and animals — not just the natives — benefit their environments and our lives.
Last month, along with 161 other immigrants from more than 50 countries, I attended an oath-swearing ceremony in Lower Manhattan and became a citizen of the United States. In a brief speech welcoming us into a world of new rights and responsibilities, the presiding judge emphasized our diversity. It is, he said, the ever-shifting diversity that immigrants like us bring to this country that keeps it dynamic and strong.
These familiar words apply just as meaningfully to our nation’s non-native plants and animals. Like the humans with whose lives they are so entangled, they too are in need of a thoughtful and inclusive response.
Hugh Raffles, an anthropologist at the New School, is the author of “Insectopedia.”
http://www.nytimes.com/2011/04/03/opinion/03Raffles.html?ref=opinion
