Have we finally recognized ourselves as a species whose survival depends on clean and adequate natural resources? by Joseph Travis

At the turn of the 20th century, only a very few visionaries could have imagined how the natural world would be changed in the next 100 years.

To be sure, there were precedents and portents that would disturb the sleep of the most optimistic. The American buffalo had been hunted nearly to extinction and escalating prices for colorful feathers had provided the motivation to hunt the Carolina parakeet to extinction. Britain and the eastern U.S. had lost most of their natural forests to cutting, and the new industries of the 19th century had already delivered ash-laden air and murky rivers to their neighborhoods.

But there were also signs to raise the spirits of the most dour of pessimists. The scale of extinctions, deforestation, and pollution appeared small and efforts were already underway to protect natural resources. The United States was establishing a system of national parks for conservation and British zoologists were already raising the alarm about the effects of water pollution on fishery species.

What only the most prescient pessimists could have foreseen was the scale on which we would alter nature for the worse in the next 100 years. And what only the most ardent optimists could have imagined was the magnitude of the breakthroughs that would be made in understanding and managing nature in those same 100 years. Perhaps the only comparable precedent in human history has been the development of agriculture, a practice that enabled the human population to explode but that also altered the natural landscape beyond recognition. The fact is, the saga of our relationship with our natural resources in the 20th century is a story of good and bad, light and darkness, optimism and pessimism, achievement and failure, with only the scale of each setting the century apart from the ones that preceded it. To chronicle the century's destructive effects on our natural resources is to recite a well-known litany:

• We have fouled our air, water, and soils on an enormous geographic scale with pollutants whose chemical compositions were not imaginable at the turn of the century.
• We have exploited fisheries and forests to exhaustion, and our methods for cutting down tropical forests, and the effects of losing so many trees, have altered the climates of regions thousands of kilometers away.
• We have instigated a mass extinction of species comparable to the great mass extinctions of geological history.

Even many of our good intentions have wrought havoc. We have introduced species from one part of the world to another for a variety of reasons, from the aesthetic to the utilitarian, and some of those introductions have become a lasting curse. Southerners in the U.S. know all too well of kudzu, that durable vine that was introduced to stabilize soils against erosion and that now overruns huge areas of our landscape. Melaleuca trees, introduced into south Florida to help drain swampy soils for development, succeeded beyond expectation, and now stands of melaleuca draw so much water from the ground that they create drought conditions for the surrounding native plants, driving them toward extinction.

In many cases, our environmental catastrophes happened quite inadvertently. Who in the South has not cursed the inadvertent introduction of fire ants through a timber shipment into Mobile? And who does not bemoan the inadvertent introduction of foreign fungi that blighted the American chestnuts and elms to virtual extinction? Gypsy moths have devastated the forests of the northeastern U.S. and Hydrilla verticillata clogs waterways from Florida to Maryland.

Our proclivity for cutting trees, paving the land, and altering the course of rivers has added to the carnage and, indeed, accelerated it. Gulf coast sturgeon have been brought to the brink of extinction by dams built across rivers they need to swim to spawn. Destruction of wetlands have put untold species of amphibians on the brink of extinction. The legendary marine life of Florida Bay has been decimated by the combination of our altering the volume, timing, and pattern of water flow from the Everglades with the addition of an enormous nutrient load from agricultural and other human discharges.

Unfortunately, our positive achievements are much less well-appreciated, perhaps because they are arguably less visible to the average person. Yet these achievements are as distinctive from those in previous centuries as are our blunders.

Perhaps the most striking of these achievements are those that allow us to reverse the deleterious effects of pollution. Part of this achievement is legal; in the U.S., we have laws that regulate a myriad of potential environmental effects. Environmental law has become a substantial discipline in American law schools, a discipline that might have been unimaginable to a legal scholar writing in 1899.

The other part of this achievement is technological. We have developed technologies that will cleanse our water, reclaim our soil, and preclude our fouling the air, without driving the industries on which we rely to bankruptcy. One need only compare the Cuyahoga River of Ohio in the 1960's to today; the river has gone from the butt of a Randy Newman joke ("Burn on, big river") to a living testimony for innovative technology. The U.S. also has created a system of protected landscapes that has no precedent in human history. The American system of national parks, national forests, and national wildlife refuges has no parallel anywhere else in the world. Together with the state parks, forests, and recreational areas, they preserve and protect a substantial part of our landscape.

One of the best examples of this investment in protection is enjoyed by countless Americans each year in the national parks, forests, and wildernesses that cover the southern Appalachian mountains. This system of protected areas, from the Great Smoky Mountains National Park to the Blue Ridge Parkway and Skyline Drive, is one of the lasting legacies of Franklin D. Roosevelt's New Deal. What most awestruck visitors to the area may not appreciate is that most of it had been cut over and cut down by Roosevelt's time, with the concomitant loss of the animals that relied upon what had once been a vast temperate forest. What visitors see now is the result of a rapid regeneration of the forest and the repopulating of its associated plants and animals. The same comparison can be made between the thick forests of present-day New Hampshire and Vermont and the pastures and fields that covered that landscape a century ago, or between the vast pine forests of present Piedmont North Carolina and the cotton plantations and old fields of the late 19th Century. With protection, nature can return to its own.

The lesson of protection and recovery is also clear in the sagas of many species that have returned from the brink of extinction. In these cases, protection from hunting and the preservation of suitable habitat has allowed recoveries at rates more rapid than we might have hoped. Anyone who has counted alligators in the southeastern U.S. or European bison on the steppes knows first-hand how rapidly an endangered species can recover if the right conditions are provided. The very symbol of the country, the bald eagle, has recovered from its precarious position, thanks to the proscription of DDT and the conservation of the wetlands and marshes in which the eagle lives.

Of course, the success of reforestation and the recovery of endangered species might be considered merely matters of dumb luck. After all, we merely had to stop hunting or poisoning the animals, or stop clear-cutting the trees, and nature restored itself. Indeed, this is the reasoning behind many well-intentioned proposals to restore fisheries; it is hard to disagree with the simple argument that if we just limit the catches somehow, the depleted stocks will rebound eventually.

Yet just as we have learned to clean our polluting substances, we have also learned to manage natural systems and hasten their recovery. The recovery of peregrine falcons in the U.S. was surely impossible without the proscribing of DDT, but just as surely it was hastened and enriched by the enormous efforts devoted to captive breeding, careful reintroductions, and active management of the remaining breeding stock. The successful recovery of redfish in the waters of the western Gulf of Mexico is another example. The effort to restore the redfish stock involved banning certain types of net fishing, limiting recreational catches, protecting key habitat, and enhancing the stocks through aquaculture and reintroductions of hatchery-reared fish. Although scientists still debate the relative importance of each component, no one could argue that the entire ensemble of efforts has not been successful.

As these successes suggest, the 20th century brought us an amazing explosion of scientific knowledge and technology that can be brought to bear on the problems we face with our natural resources. In fact, we now know the broad principles that can be used to solve almost any environmental problem in the world. This knowledge is a direct result of the strong governmental support for scientific research in ecology and resource management that has characterized the latter part of our century, in the U.S. and elsewhere. This support has absolutely no precedent in human history and, indeed, the changes in all aspects of our lives in the last 50 years testify eloquently to how successful this support has proven.

But if we have so much knowledge, why do we continue to have so many problems? And why do so many scientists tell the public that we need more research to find out how to solve our environmental problems?

There's a simple answer to both questions: We have problems because we don't like the direct solutions that scientists offer us and the solutions we want are not easy to find. From the scientific point of view, the best course of action is usually clear. If we want our lakes and rivers to remain pristine and full of fish, we should limit sharply the development of their shores. If we want sustainable fisheries, we should limit the harvest. If we want clean air and soil, we should require stringent scrubbing of industrial discharges. Of course, these solutions aren't always practical. In reality, we want beautiful, clean lakes and rivers so that we can live on their banks and enjoy them. We want sustainable fisheries so that we can enjoy affordable seafood throughout the year. And we want pure air and soil so that we can enjoy ourselves with the increased leisure time that technological advances allow us. These realities force scientists to solve a more complicated problem, which is to find the optimal management strategies that would balance our desire to protect our natural resources with our desire to use them.

But this need for balance moves the limiting step for managing our natural resources out of the scientific realm and into the economic, social, and ethical realms. Before the scientists can begin their work, we members of society must answer some difficult questions. Exactly how "natural" do we want our lakes to remain? How many houses do we want to build on their shores? What level of "unclean" or "unnatural" are we willing to accept? How much are we willing to pay to maintain our desired level of "naturalness"? How much are we willing to pay for our grouper fillet? How much are we willing to pay for our new tires? What is our ethical obligation, if any, to restore species brought to the brink of extinction by our own actions? How much money are we willing to spend on that restoration? How much land do we wish to set aside for conservation and where are we willing to place those protected areas?

And so it is no wonder that as the century is about to turn, we find ourselves still struggling to manage our natural resources. The dilemma we have is that we often fail to attain a consensus on answering the key questions that would direct the scientific effort to find the best answers. Lacking consensus, the measures we take are often based on unrealistic expectations and unattainable goals. The failure of so many well-intentioned laws and regulations to protect Florida's water resources illustrates this point. The greatest challenge for the next century will be to achieve consensus on how we wish to balance protection and use of our natural resources. A lack of consensus will ensure that despite a breathtaking pace of scientific advances, our environmental mishaps will continue to overshadow our achievements.

"History deals mainly with captains and kings, gods and prophets, exploiters and despoilers, not with useful men." H.L. Mencken