Seedlings grow at a large, state-owned, tree nursery near the city of Guarapuava, Parana state, Brazil. ©Scott Warren
“Anytime we have the hubris to think we can separate ourselves from nature, we are prone to some profound foolishness.”
Peter Kareiva, Chief Scientist for The Nature Conservancy
Is there any wilderness left? An article in Science magazine co-authored by The Nature Conservancy's chief scientist says not really — and that conservation's task is no longer to "preserve the wild, but to domesticate nature more wisely."
While human history has been defined by the domestication of species, the article cites strong evidence that nature itself has already been almost completely "domesticated":
- There's nearly six times as much water held in storage (e.g., behind dams) as there is in free-flowing rivers.
- About 50 percent of the world's surface area has been converted to grazing land or cultivated crops.
- And only 17 percent of the world's land area in 1995 was untouched by the direct influence of humans (such as agriculture, roads or even nighttime lights.
"There really is no such thing as nature untainted by people," write the authors. "In the modern world, wilderness is more commonly a management and regulatory designation than truly a system without a human imprint."
And the article goes further — arguing that many ecosystems services (the goods and services nature provides humans) are declining because we are domesticating nature to maximize food and timber production while ignoring the consequences of that choice.
Nature.org asked Peter Kareiva, the article's lead author and chief scientist at the Conservancy, how we could better manage such choices — and where the wild went to.
Nature.org: So there's really no more "wild" left?
Peter Kareiva: I’d rather say there is no more pristine wilderness left. In fact, many places we once thought of as "virgin rainforests" (for instance, in the Congo and the Amazon) show evidence of having been cleared for slash-and-burn agriculture over a thousand years ago.
Luckily, you still can find wild in terms of grizzly bears or tigers, or untamed river rapids. But even in those adventurous places, there is almost always a strong signature of human impacts — either an invasive species, or perhaps a wide-ranging pollutant, or the absence of some large grazing animal or dangerous predator that we exterminated years ago.
Nature.org: Has it always been misleading to think about nature as apart from human activity? Or has there been a fundamental shift recently in the risks we run in domesticating nature?
Peter Kareiva: Yes — it’s always been a mistake to think that over here are humans and human activities and then over there is nature.
However, 100 years ago, this mistake was a small one. Now it is a huge mistake simply because there are more of us humans — and anytime we have the hubris to think we can separate ourselves from nature, we are prone to some profound foolishness.
Just look at our food production systems, which often are viewed as open-air factories as opposed to what they are: natural ecosystems that depend on pollination, clean water, fertile soils, and natural enemies of crop pests.
Nature.org: You argue that domesticating "vast landscapes and entire ecosystems" has often had unintended negative tradeoffs. Tell us about some of those tradeoffs.
Peter Kareiva: Humans have domesticated nature for greater productivity, greater safety, and convenient commerce. We have been pretty successful at this, and all of these are good things. But most of the time, these benefits come with some costs or tradeoffs.
Take commerce, for example. Because of the global transportation network that supports commerce, invasive species and diseases can spread around the world at unprecedented rates and speeds. This is not just about biodiversity. Within a few months of first appearing in China, severe acute respiratory syndrome (SARS) had spread from China to 26 countries and five continents. The good comes with some bad.
Some tradeoffs are gradual and readily observed and can be managed for. (One obvious example: If you use water for irrigation, you have less water for fish in streams.) But other tradeoffs may be invisible until it is too late.
An example of the latter might be the dead zone created by the Mississippi River’s enormous nutrient load. As more and more nutrients were loaded into the Mississippi, we didn't see a progressive deterioration in what is now the dead zone. We instead say an abrupt switch to a highly degraded state.
Nature.org: So what would "domesticating nature more wisely" look like, specifically?
Peter Kareiva: No one I know of has thought carefully enough about this question to give an answer anyone should take too seriously. But I would argue that, while domesticated nature would inevitably have a large human footprint, it would also include enormous landscape and biological diversity amidst this human presence.
Moreover, instead of nature sequestered off in nature reserves, we would have some nature reserves and support and embrace nature in urban environments. With more than one-half the world's population now living in cities, we will gradually lose public support for conservation if we do not bring nature to people in cities.
Nature.org: Speaking of cities, you say in the article that cities — because of their big ecological footprints — are "a good place to start when considering broader implications of domesticated ecosystems." Don't we already know that cities are having a negative effect on those ecosystems? Isn't it just a question of publicizing that better?
Peter Kareiva: You've framed the question all wrong. Cities and the billions of people who live in them exert a form of selection on ecosystem services.
We have choices about what attributes cities promote, and what attributes cities ignore. If cities want viewsheds, that will be one type of ecosystem they create. If cites do not care about viewsheds but just want lots of freeways, that is different type of ecosystem.
Conservation should be about choosing the future natural world in which we want to live and our children to live. Our emphasis should be on choosing the future, not on clinging to some vision of how beautiful things once were (when they likely were not even as we thought they were).
Nature.org: But shouldn't we be setting aside more protected areas? Or will those inevitably become encroached by human activity, too?
Peter Kareiva: Of course we should be setting aside protected areas. But there is no such thing as a protected area that does not need active management, which further reinforces the extent to which nature is pervasively domesticated.
And as populations continue to grow, the success of conservation will have a lot more to do with how well protected areas are managed to handle heavy use and encroachment from humans as opposed to how many acres we have protected.
For example, an analysis I did with colleagues at Harvard University reveals that, by 2030, more than one-quarter of the protected areas in Western Asia will be within 4 kilometers of a city; in Northern Africa, one-quarter of the protected areas will be within 6 kilometers of a city; and in southern and western Europe, one-quarter of the protected areas will be within 3 kilometers of a city.
Think about that. All of those protected areas — these areas that we count as contributing to our goals — are within an hour’s walk of an urban population. So is our challenge only to make more protected areas, or shouldn’t we also be making sure our urban populations value those protected areas?
Nature.org: Why are you optimistic that science can inform the kind of economic and political decisions that have to this point almost completely disregarded the degradation of nature?
Peter Kareiva: I am optimistic because conservation scientists are getting smarter. Until recently, conservation and environmental scientists spent most of their energy sounding doom-and-gloom alarms, bemoaning how greedy and stupid we humans are, and telling us to stop doing this or that. I think the trend now is to instead use science to depict plausible scenarios as a result of basic public and societal choices, and in doing so making clear our choices for the future.
If scientists can paint the choices instead of being prescriptive know-it-alls who tell the world what to do, there will be a lot of hope. Better yet, if science can get us to experiment with land and water management, then we can tap what I think is one of the most profound ideas of all time — the power of experimentation.