REINDEER, CARS & MALTHUS: POPULATION, CONSUMPTION AND CARRYING CAPACITY by Denis Hayes

REINDEER, CARS & MALTHUS
POPULATION, CONSUMPTION AND CARRYING CAPACITY

by Denis Hayes

In 1944, reindeer were introduced to St. Matthew Island off Alaska in the Bering Sea. During the next 20 years, under exceptionally benign conditions, the herd grew explosively to 6,000 reindeer. Then, in the fierce winter of 1964, it crashed to just 42. The deer had overgrazed the lichens that were their main source of winter forage and, in a severe winter, the vast majority starved to death.

The St. Matthew Island deer followed a standard ecological model. When biological controls--such as food limits, disease, or predators--are removed from a species, the population grows explosively. Eventually, the population exceeds the carrying capacity of its environment. Sometimes favorable conditions permit a species to expand temporarily far beyond its long-term carrying capacity. This always leads to a catastrophic collapse. This pattern is followed by elk, trout, ladybugs, and every other creature with an instinct to "be fruitful and multiply."

Carrying capacity is an ecological concept that measures the largest number of any species that a habitat can support indefinitely. For most species, it is fairly easy to determine.

However, for human beings, carrying capacity is not determined simply by assessing population and resources. Our species is able to think abstractly, to envision contingent futures, to make strategic choices. The choices we make in lifestyles and technologies have enormous implications for how many of us a biological system can support over the long haul. For example, whether or not a society has automobiles greatly influences the resources needed to sustain it. Conversely, the choices we make collectively about the size of our population will determine what lifestyles we will be able to enjoy.

For example, China and the United States encompass about the same amount of land--roughly 3.6 million square miles. The US population is about 281 million people; China's, at 1.3 billion, is almost five times as high. The United States could support 1.3 billion people, at a Chinese standard of living, for quite a while. However, China will never be able to support 1.3 billion people at an American standard of living.

Similarly, today's global human population of 6.1 billion far exceeds the planet's carrying capacity if the average person is to enjoy the current lifestyles and technologies of the United States. Since World War II, Americans have consumed more of the world's mineral wealth than all other people in all societies throughout the entire course of history before the war. If everyone consumed at the American level, all the world's oil reserves would shrink to just a few year's supply; all the world's old growth rain forests would disappear in less than a decade; the build-up of toxic wastes might alarm even Rush Limbaugh.

Until the past few decades, human numbers posed no special danger to the earth. Today, however, Homo Sapiens is literally devouring the planet. So far, we have destroyed about 12% of the net biological productivity of the planet, and we use an additional 27% directly and indirectly. In other words, our species has laid claim to about 40% of all the sunlight that is fixed by photosynthesis and that ultimately provides all the energy that sustains life on earth. While we take 40%, other species are currently experiencing what Harvard biologist E.O. Wilson characterizes as the most calamitous biological collapse in 65 million years.

Much of human population makes only minimal demands upon the resources of the planet. Even so, the world's major biological systems are approaching their limits. Food and fiber production have leveled out everywhere over the past five years. Virtually all the best land is in production (along with much marginal land where agriculture cannot be sustained in the long run), and recent increases in fertilizer use have yielded no significant gains. All the world's major fisheries have plateaued, and many--including the salmon fisheries of the Pacific Northwest and the cod and haddock fisheries of New England--are collapsing. Vast tracts of wilderness, teeming with myriad creatures, are being reduced to tiny biological reserves.

What will happen as other peoples develop economically and seek some of the material well-being that we enjoy? For example, China plans to triple its coal use by 2010. If it succeeds, it will then be releasing about 50% more carbon dioxide into the atmosphere than the US does today.

All the world's major environmental issues--forestry, fisheries, healthy air and water, toxic wastes, sustainable energy sources, sensible transportation systems, etc.--will eventually be overwhelmed by a growing population, unless we choose a different path.

A thoughtful study of global human carrying capacity was released in early 1994 by David Pimentel, a professor of biology at Cornell University. Professor Pimentel calculates that, if the most benign and efficient technologies are universally embraced, the world can permanently support a human population of 2 billion people at a lifestyle that resembles middle-class life in today's industrialized nations.

The bad news is that the world's population is three times that high already. The good news is that we could choose to reduce the human population to 2 billion people in about 100 years without having to experience a catastrophic collapse caused by starvation, plague, or war. It would require that every family on earth have an average of 1.5 children.

How realistic is this? Germany has already reached it, averaging just 1.5 children per family. Hong Kong has 1.4. Italy--among the most Catholic of all countries--averages 1.3. Unfortunately, in many other countries, family sizes average from 5 to 9. The task of reversing this cultural preference for huge families is daunting.

The 1994 Cairo Conference on Population and Development laid out a grand strategy for the world. The next steps must be taken by nations, regions, states, cities, and individuals. If we wish to keep our communities livable, our farms productive, our forests healthy, our fisheries vigorous, our remaining wild rivers undammed, we need to develop a widely supported, regional population strategy. We need to have the courage to endorse tough-minded goals, set realistic milestones, and establish public policies that support these ends.

When I couch the issue in these broad, vague, courageous-sounding terms, it is hard to disagree. However, I believe that carrying capacity--the trade-offs between sheer numbers of people and the quality of their lives--could emerge as one of the most emotionally pitched issues on the political landscape.

There are many ways that the issue could rapidly achieve national prominence. Already, immigration-related issues sizzle in the four most populous states: California, New York, Texas and Florida. If immigration-driven growth expands into other states the inexorable forces of national politics may quickly expand the debate. One of the first questions will be whether immigrants should be eligible for preferential hiring, set-aside college admissions, or other forms of affirmative action aimed at historically excluded groups.

Without attempting to settle anything in this brief article, let me quickly flag some other highly contentious immigration questions we could soon find ourselves confronting.

How many immigrants should the United States accept each year? The 1972 Rockefeller Commission suggested 400,000. The 1981 Theodore Hesburgh Select Commission recommended 350,000. The Federation for American Immigration Reform wants 300,000. Currently it varies between 1 million and 1.5 million legal immigrants per year--more than 1/3 of our total population growth. This number is a political choice. Is it a good choice?

Where should these immigrants come from? Liberals would say we should be indifferent. But unless we simply open our borders to all comers, we must have some criteria to determine who is admitted, and those criteria will have consequences. As a result of the Immigration and Nationality Act of 1965, we ended national quotas and introduced the "family reunification" principle. This has had fascinating, and wholly unexpected, consequences for the nature of the immigrant pool.

Not to beat around the bush, the overwhelming majority of America's immigrants during the nations first 200 years came from Europe. Sooner or later, Patrick Buchanan or David Duke or one of Bull Conner's other heirs will notice that our immigrant patterns, when coupled with differential birth rates among ethnic groups, are changing the racial makeup of the society. In 1960, the United States was 88.6% white. By 1990, it was 75.6% white. Under current patterns, whites will cease being a majority around 2050--and of course they will cease being a majority in some states and regions long before then.

Whether you view this as good or bad may depend on where you stand. For example, the greatest losers at the moment are African Americans who find themselves competing for education, training, scholarships, and jobs with immigrant people of color. Moreover, these newly-arrived Americans typically have no sense of guilt over past American injustices, and often express widespread hostility to blacks. Tensions in many transitional neighborhoods are palpable, and are registered through ethnic gang violence.

REINDEER, CARS & MALTHUS POPULATION, CONSUMPTION AND CARRYING CAPACITY

REINDEER, CARS & MALTHUS
POPULATION, CONSUMPTION AND CARRYING CAPACITY