Population and Habitat
It is largely population growth - not an increase in per capita consumption - that is driving the environmental destruction we see across the globe today.
One Step Forward, One Step Back
The United States can -- and must -- do a great deal more to slow resource use of all kinds. No country on earth uses natural resources at the rate of American consumers.
The good news is that "recycle, reuse and do without" is slowly becoming a mantra among a growing segment of our population. Even those with little interest in the environment, recognize that waste is expensive, and that significant savings can be had through modest investments in water and energy conservation.
Speeding the pace of resource conservation have been real improvements in agriculture, forestry, milling and production which have resulted in significant per capita declines in many resource areas.
The bad news is that U.S. population growth has negated much of these conservation gains. For example, while the U.S. reduced per capita oil consumption by about 25% between 1978 and 2000, the population of the United States grew by this same amount. In the end, the "one step forward" we made through energy conservation was negated by the "one step back" we took through population growth.
Along the same lines, while we can look at forest and farm and see real gains in terms of productivity-per-acre (see column to the left), we can also see increased habitat loss for some species due to these productivity gains. For example, increased forest fragmentation across the U.S., combined with intensive mowing of hayfields, has resulted in a widespread decline in deep-forest nesting and grassland-nesting birds.
Overseas, a combination of population growth and increased consumption is rapidly expanding the ecological footprint of many people in many countries. Here too, however, technology is working to soften the blow.
- Aquaculture, for example, now accounts for 22% of the world's fish harvest -- most of it pond-based carp production in Asia.
- A combination of high-yield forest plantations and a switch from wood-fuel stoves to propane is starting to slow deforestation rates in some part of India., Africa and Latin America.
- Yield improvements that came during the "Green Revolution" of the 1960s and 70s helped slow the expansion of farmlands into wild areas.
Between 1961 and 1999, per capita land use for nonfuel wood declined by 18 percent, per capita land use for grazing declined by 8 percent, and per capita land use for crops declined by 44 percent. . . . Only in the arena of fishing grounds do we see a dramatic increase in per capita wildlife habitat use.
A World Too Small?
A billion people will be added to the world's population in the next 15 years -- all in less-developed countries where billions of people already aspire to the basic niceties and necessities of Western life: cars, refrigerators, clean water, and reliable electricity.
No one on the earth would deny these people what most of us now take for granted, but there is also no denying that meeting the world's desire for a better way of life will also impose considerable environmental costs.
One way to look at the problem is to consider how big the world would have to be if everyone lived like Americans did, with good food, ready transportation, a newspaper delivered to our door and a refrigerator in the kitchen. The folks at "Redefining Progress" have put together a quick and relatively accurate "Ecological Footprint Calculator" to give people an idea of how big the world would have to be if everyone lived like we do here in the U.S. The default answers on this web site represent North American averages.
Despite declining per capita resource use due to technological improvements and a growing conservation ethic across the globe, wildlife habitat loss continues apace, with human population growth being the primary engine of destruction.
As Table 1 (above) makes clear, the total "footprint" of humans is rapidly increasing across the globe, with people consuming increasing amounts of land, fresh water and ocean resources in order to satisfy their needs.
Between 1961 and 1999, per capita land use for nonfuel wood declined by 18 percent, per capita land use for grazing declined by 8 percent, and per capita land use for crops declined by 44 percent.
Fresh water consumption rose and then fell (largely due to conservation efforts in the developed world), and in the end there was no increase in per capita use.
Only in the arena of fishing grounds do we see a dramatic increase in per capita wildlife habitat use.
Ocean fishing represents a global trade in wild game. A combination of increased per capita consumption of fish, combined with a doubling of the human population over the course of the last 40 years, has resulted in overfishing in all 17 of the world's major fishing grounds.
Fast Facts on Conservation
While Americans remain the most rapacious consumers of natural resources in the world, we are making some progress thanks to energy and resource conservation efforts and improved manufacturing and production techniques. Some examples:
- U.S. farmers are growing far more food per acre today than they did 40 or even 20 years ago. As a consequence, the "wildlife footprint" of the average American has gotten smaller, not larger. As productivity-per-acre has gone up, the U.S. has been able to allow marginal agricultural lands to return to forest or be put into conservation reserve programs.
- In the U.S. we are using less grazing land per capita than we did 40 or even 20 years ago due to changes in the way we raise beef and dairy cows and the mechanization of hay fields. While we have 10 to 12 million fewer acres in hay today than we did in 1950, we are seeing record levels of hay production.
- In the U.S. we are using less forest per capita than we did 40 or even 20 years ago. Modern lumber mills waste less wood and modern forest managers know a great deal more about both sustainable wild forest management and the rapid growth of pulpwood on tree plantations. As a consequence, the per capita use of forest land in the U.S. has actually declined, not increased, in the last 40 years.
- We are using less oil per capita than we did 25 years ago. U.S. oil consumption has declined from 31 barrels per person per year in 1978 to 25 barrels today -- a 25% decline. The savings we have made through energy conservation, however, have been largely negated by U.S. population growth.