Warming worries: Wolverine may get endangered status

On Feb. 1, 2013, the U.S. Fish and Wildlife Service proposed adding the wolverine — a tough, reclusive carnivore that lives in the snow in the Rocky Mountains — to the endangered species list. About 300 of these weasel relatives survive amid the heavy snows and severe climate of the high mountains, but global warming is melting their habitat.

The International Union for Conservation of Nature (IUCN) lists 10,820 animal species worldwide. The group’s “Red List” does not distinguish endangered from threatened species.

And now comes the accelerating threat of global warming, a planet-size problem that is sure to make matters worse for rare species in many places and cases. Polar bears and corals have already entered the list of species in danger due to the global changes wrought by greenhouse gases, and more species are doubtless coming, due to changes in precipitation, temperature, disease, ocean acidity, and the timing of flowering, fruiting, migration and the very seasons on our planet.

The Wolverine — no relative of the wolf — is perfectly adapted to the snow, with paws serving as natural snowshoes and dens deep below the snow that are warmed by the lack of wind and insulation from the snowpack. The animals “use snow as a natural refrigerator, caching their food in natural ice boxes,” to sustain them as they bear and nurse their young, says Jonathan Pauli, an assistant professor of wildlife ecology at the University of Wisconsin-Madison. “They are losing this natural refrigerator, which is really problematic because it affects this nutritional pinch point in early spring.”

The wolverine and other snow-dependent mammals are on a collision course with a warming climate, says Pauli. “The winter climate in particular in the Northern hemisphere is changing dramatically. In the last 100 years, we’ve seen an increase of three-quarters of a degree Celsius, and what’s especially relevant is the shortening of the duration and depth of the snow cover. The snow season is being compressed,” he says.

The signature of global warming can be traced to about 1980. All of the top 10 warmest years, including 2012, occurred after 1997.

National Climatic Data Center

The American Marten is another winter specialist that hunts mice under the snow, but some populations are in trouble. “They are a winter-adapted carnivore,” says Pauli. “They are light and their feet, like the wolverine, are a natural snowshoe” that saves energy. Sinking into deep snow is tiresome and “can put you on the nutritional redline. It’s not just exhausting, it can be deadly.”

The American marten was extirpated from Wisconsin in the 1920s, and reintroduced in the 1950s and again in the 1970s, but they are not prospering, and one possible explanation is the truncated snow season, Pauli says.

Turning turtles

It’s tough to pinpoint the role of a changing climate on endangered species. After all, as pioneering ecologist Barry Commoner said, the first law of ecology is that everything is connected to everything else; nothing exists in isolation. “I don’t know how much hard data there is on a lot of species relative to climate change,” says Scott McRobert, professor of biology at Saint Joseph’s University in Philadelphia. “Although it is probably causing dramatic effects to a large number, it’s hard to isolate climate change from other factors.”

That calculus is evident in the leatherback marine turtles which “have declined exponentially since we started studying them in 1989,” due to hunting of turtles, gathering of eggs, and fishing gear that snared turtles as “by-catch,” says James Spotila, professor of environmental science at Drexel University.

Changing climate is fueling more of the periodic warmings in the central Pacific called el Niño, Spotila says. “When the Pacific warms, there is less [nutrient-rich] upwelling, so the turtles have a harder time getting food,” which impairs growth and reproduction, he says. “Our studies and mathematical model show they will be gravely affected by a changing climate, and it’s starting now.”

Leatherbacks and other marine turtles face a second difficulty related to warming: The sex of hatchlings is determined by temperature while the egg develops; when it’s hotter, more females develop. The result is that most turtles developed from eggs laid in January and February are female, says Spotila.

On Colombia’s Caribbean coast, 92 percent of leatherbacks are born female in some years, and the temperature anticipated for 2050 will make virtually all of them female. Indeed, a 2012 study.² warns that “complete feminization could occur, as soon as the next decade.”

Without males, a population crash is inevitable.

Heat by itself is also a problem, says Spotila: “As the season progresses, the hatchlings become weaker and more heat stressed. In April [on Costa Rica's Pacific Coast], there is very low hatchling success due to heat stress.”

Climate change is “a giant bummer,” Spotila says. “We spent 23 years setting up Las Baulas National Marine Park, protecting the beach, and getting a handle on fishing. … The overwhelming effect of global warming is going to make life even more difficult. We are going to see species after species getting these problems.”

Walking that long Amazonian road

In the vast tropical forests that survive in Amazonia, climate change will scourge many habitats, according to a new study.³ Kenneth Feeley, assistant professor of biology at Florida International University, asked how far residents of large ecological situations — biomes — would have to move to find suitable habitat by 2050. “The classic way has been to look at the effect of deforestation or fragmentation as almost one field of conservation biology, and a separate field of climate change ecology,” Feeley told us. “There hasn’t been that much study of both simultaneously.”

Feeley combined these threats. “We looked at the conditions you find in a spot in the Amazon, and asked where would you have go to find the same temperature and precipitation” in 2050, he explains.

And he then blocked off areas that would require traversing large, deforested areas. Already, he notes, many Amazonian animals “are really hesitant to cross a break, a trail, a road or a river,” so requiring animals to avoid deforested areas “shows the true distance that a species has to move.” Large-scale deforestation “creates environmental traps for species, because there is no way to reach the future climate area without crossing a deforested area,” Feeley says.

In many cases, he says, animals would have to travel “off the map.”

Minimum distance to suitable habitat in Amazonia, 2050

Map at left shows how far species would have to move to find today’s climate after expected changes in temperature and precipitation. Map at right adds in effects of deforestation. Because most organisms cannot cross farm fields, they will have to travel much further to find livable habitat. Organisms now living in the black zones will be homeless.

Both maps used with permission; Feeley and Rehm. Amazon’s vulnerability to climate change heightened by deforestation and man-made dispersal barriers. Global Change Biology. Blackwell Publishing Ltd.

We commented that his maps were profoundly depressing, and Feeley cheerlessly reframed them as best-case scenarios. Organisms, he noted, are inter-dependent: If bird A is needed to pollenate flower B, “that just compounds the difficulties, because both have to arrive simultaneously. And they might depend on a third species. If they do not all arrive simultaneously, it might be impossible for each species to be there.

“The forecast for Amazon biodiversity is really grim,” says Feeley. “Our only hope is that we are wrong.”

What to do?

Scientists are starting to test some tentative fixes for the biodiversity ravages blamed on a changing climate. Many proposals favor preserving more habitat, while choosing more selectively. “We can envisage ways to manage land cover that would mitigate or reinforce the changes we expect,” says Pauli. For example, “Different land-cover types can have a strong effect on ambient conditions in winter; areas with forest cover can have much more moderate temperature than open areas.”

Here are some other ideas we culled from a survey of the changing landscape of hot-world biodiversity preservation:

✻ Mapping migration

The new maps of Amazonia could help in designing migration corridors so species can move as climate changes, says Feeley. “If we know this area will be lost to agriculture, can we plan to place corridors in the most effective places? A lot of the focus in conservation has been on preserving parks, assuming static conditions. Now we are talking more about the need to protect areas to allow species to respond to climate change,” he says.

✻ Change the habitat

Since temperature controls the sex ratio in leatherbacks, Spotila and others are testing whether fresh-water sprinklers and sunshades can cool the beach in Costa Rica to stabilize the male-female ratio and improve hatching success. “We are doing the experiment now, trying to determine which of those options will work,” he says.

Aided by the Climate Adaptation Fund, the Grand Canyon Trust is reintroducing beavers into 87 stream segments in Southern Utah. Rollover to see the change one year later: the new beaver pond has already drowned invasive plants while creating habitat for native plants and animals. Check the video.

First: July 2011, photo by Natalie Jamerson, Whitman College; second: September 2012, photo by Allison Bolgiano, Whitman College

✻ Put wildlife to work!

Beaver dams naturally store water, replenishing aquifers and restoring wetlands for wildlife, while reducing floods and the effects of drought. Now, after centuries of trapping, beavers are returning (via foot or truck) to various landscapes, including the arid Southwest, faced with drought and highly erosive floods in the changing climate.

✻ Trucking to a better home?

Moving animals to habitat that remains hospitable in the new climate may be a last resort for animals like the endangered blue-tongued lizard, whose native grasslands in South Australia have been transformed by farmers and now climate change. Some scientists have proposed building artificial burrows for the lizards, and even moving them to new locations where the future’s climate should be more benign. “Although we recognize the importance of conservation efforts to improve the quality, connectivity and permeability of the species’ current habitats, the rapidity of climate change will continue to exceed the ability of some species to adapt or disperse to more climatically favorable regions,” wrote the authors of a 2012 relocation study.⁴

✻ More shelter from the storm

Captive breeding has been used to sustain whooping cranes and other animals threatened with extermination in the wild, and McRoberts keeps several endangered turtles from Asia or South America in “assurance colonies” in his lab. “At least we can keep some of them alive in the hope that there might be places where they could live in the wild,” he says. As McRoberts recognizes, captive breeding could deflect time and energy from habitat conservation. “Even as someone who does it, I am not saying it’s an optimal way of saving species, but I don’t see it detracting from survival in the wild,” he says. “It’s best to approach any conservation issue from as many different points of view as you can.”

Endangered Species Act to the rescue?

Our story started with the potential listing of the wolverine under the Endangered Species Act, a pioneering law premised on the avoidance of extinction. But a 2012 study⁵ of ESA plans for endangered species in the American West found that “few [climate] adaptation projects have made it to the implementation phase,” due to budget constraints and lack of specific direction from the government agencies involved.

Newer habitat conservation plans should pay more attention to climate, says study author Paola Bernazzani, of the Ohio consulting group ICF International. “There are some good plans coming out in the future, but since we looked retrospectively, there was not anything that did a good job,” she says.

The inability to pinpoint the details of future climate and habitat should not excuse the failure to plan for changes, Bernazzani says. “We admittedly don’t know everything we would like to know to plan for 30 or 50 years, but … the Endangered Species Act was written to anticipate flexibility by calling for adaptive management.”

In a forthcoming plan, Bernazzani says, her company is using computer modeling to explore how fish will move through hydroelectric dams: “We are able to alter the scenarios to fit different climate-change assumptions, and we’ll test them. It’s like a fire drill — you know before implementation what are some potential outcomes.”

Habitat plans may also require establishing preserves to buffer against climate change, Bernazzani says, but the reality is that “we are talking about species that are already rare, and adding one other pressure on top, and I am not sure all the conservation planning in the world is going to solve that.”

The bottom line

Back in the 1980s, climate change was tomorrow’s trouble. Not any more. “There is no question that climate change poses an unprecedented challenge to biodiversity,” says Pauli, the mammologist at the University of Wisconsin-Madison. “It’s one of the biggest conservation crises we are facing.”

To a specialist in winter ecology such as Pauli, the truncation of the snow season “is challenging and frustrating, but it does provide an opportunity to understand the winter system; it’s an experiment that unfolds in real time.”

The reality is that the disruptions due to climate change are seamlessly connected to everything else, says McRoberts. “It’s always very difficult to say a species is encountering difficulty from one direction, and every endangered species is also encountering other problems, habitat destruction being the primary one,” he says.

McRobert agrees that it can be daunting for people who have worked for decades to preserve biodiversity to gird themselves to combat a threat with a global reach. “There are so many issues that you can be overwhelmed easily,” he says. “If you are worried about habitat for endangered species, you should keep working on that” instead of worrying specifically about climate change. “It’s hard to address everything at once.”

Space rocks falling down. Time for a meteorite hunt?

The biggest meteorite in a century struck Chelyabinsk, Russia, on Feb. 15, when an asteroid about 55 feet (17 meters) across, with a mass of 10,000 tons, exploded in the upper atmosphere. The explosion and fireball released about as much energy as a 500-kiloton atomic bomb — 30 times more than the bomb that devastated Hiroshima in 1945.

Shock waves through the atmosphere caused widespread destruction. Flying glass from thousands of broken windows was the major cause of an estimated 1,200 injuries.

But as the physical and emotional shock wore off, residents began collecting fragments. Soon, as happens after any substantial meteorite falls, professional meteorite hunters and go-betweens were buying fragments of space rock from locals.

Twenty five years ago, this would not have happened, but both amateur and professional interest with meteorites has exploded, says Geoff Notkin, co-host of the cable TV show Meteorite Men. “I have been in the field for almost 20 years, and when I first got interested, there were only a handful of people, other than a few academics. Now there are thousands of collectors worldwide, a couple of popular publications, our TV show, high profile auctions and a number of new books.”

Much of the surge in popularity can be credited to the Internet. “In the pre-Internet age, meteorite collecting was a small hobby, and meteoritics a comparatively small science. It was difficult to connect,” says Notkin. “There was no magazine, no forum. You might meet someone at a rock show, but there was no network of collectors and enthusiasts.”

The sale of major fossils to private collectors often sparks a chorus of scientific caterwauling, concerned that scientists will be barred from private storehouses sequestering significant samples of natural history. Do professional meteorite hunters and the market they feed harm science even as they cater to people who covet chunks of ancient space?

Certainly, the motivations of scientists and collectors overlap, says Ralph Harvey, associate professor of planetary materials at Case Western Reserve University. “You would not be a private meteorite collector or a meteorite scientist if you were not jazzed about stuff that falls from space. That’s clearly what we have in common.”

But motivations vary widely in the private world, Harvey adds. “Plenty of people cross the boundary well, are part collectors and part scientists. The big difference arises with people who focus on specimens as much from a financial as a scientific or curiosity point of view.”

Chelyabinsk, Russia, was a “fireball for the ages,” says Harvey. “My sympathies go out to the people who were hurt… but I would love to have witnessed that fireball from a safe distance. It’s awesome. Dangerous but awesome.”

The oldest text?

Meteorites formed as the solar system coalesced from the primordial cloud of dust about 4.56 billion years ago. Since then, their surfaces have gathered dust, and many have suffered a gigantic collision with another asteroid. In the last few seconds of their lives, they get a black “fusion” crust as they burn through the atmosphere.

Nonetheless, meteorites are unchanged in comparison to rocks on Earth, which have been altered by squeezing, heating and chemical reactions over the eons. And that makes these messengers from the deep solar system deeply important to science.

Some meteorites are not just time capsules from the ancient solar system: the most intriguing space rocks were blasted from the surface of the moon or Mars by asteroid impacts. “They are our only tangible samples of material from Mars,” says Carl Agee, director of the Institute of Meteoritics at the University of New Mexico.

Agee says even rarer meteorites — blasted from Mercury or Venus — could be lying on some farm field or ice sheet, awaiting discovery.

As meteorite hunters continue to harvest a growing roster of rocks, scientists hunger for more, says Harvey. “Meteorites are still really rare. If you looking for an answer to where it all came from, it starts with meteorites, but we have a few tens of thousands of pieces [representing] an entity as big as the solar system. The rocky inner planets have been changing for billions of years, Harvey notes, so “The only way you can get at the original conditions is in these bits and pieces that were hidden in a corner of the solar system.”

Meteorite hunting, 21st century style

Meteorite hunting has transcended the “farmer finds weird rock” phase, Harvey says. “Before 1950, virtually all of them were found by farmers in fields, maybe they were plowing and hit something, or saw it fall and rushed over to pick it up. Later, most were recovered because they hit a building, a car or a road. In the last five to six years, most are now found after being seen on a video camera or other monitoring system,” such as weather radar.

Photo: Jeff Miller

Noriko Kita, director of the Ion Microprobe Laboratory at the University of Wisconsin-Madison, removes a piece of rock, believed to be from the April 14, 2010 Mifflin meteor in Southwestern Wisconsin, from a scanning electron microscope. The fragment was found by a Wisconsin farmer and brought to the university for analysis.

After a big fireball, hordes of meteorite hunters are likely to descend on the impact zone, and they now use technology to find elusive rocks hiding across a broad landscape, says Richard Slaughter, director of the Geology Museum at the University of Wisconsin-Madison.

Slaughter, who tried his hand at meteorite hunting after a strike in Wisconsin in 2010, says hunters “have online forums and list serves; they are very strategic.” The majority of finds on a “strewnfield map” came from meteorite enthusiasts, not scientists, Slaughter says. “They are very systematic, use all the data to find the best places to look.”

Radar records and metal detectors are standard techniques to combat the “needle in haystack” problem. Metal detectors, Notkin says, are most useful for iron meteorites (typically about 93 percent iron) and stony-iron meteorites (about 50 percent iron). Detectors will also detect the more common stony meteorites, typically containing about 20 percent iron, but with more difficulty.

The Polar solution

Laws governing the collecting of meteorites vary widely, but they are unambiguous in Antarctica, where the scouring wind leaves dark space rocks exposed on the snow. Because the Antarctic treaty forbids private ownership of rock or ice samples, the U.S. Antarctic Search for Meteorites program, now in its 35th year, delivers meteorites to NASA, which catalogs and distributes them to scientists who can make a convincing case for their need.

Photo: Carnegie Mellon University

Though these rocks are probably not meteorites, the contrast between rock and ice is written in black and white. The Antarctic survey team frequently retrieves more than 100 meteorites in a day.

Harvey, who directs the Antarctic search program, says its founder William Cassidy, “knew that the meteorites would have such impact on science that we should give the samples away and not lay any claim on them. It’s as if a scientist walked through the Brazilian jungle and found a lost civilization, and said, ‘Let me call the 50 best people to investigate, and I’ll step back.’ It’s incredibly altruistic.”

At the other extreme, meteorites in the United States belong to the owner of the land they smash into. In 2012, the U.S. Bureau of Land Management issued new rules that permit “casual collection” on BLM land, but require a permit for commercial and scientific collectors.

The human element

The growing number of people who march, heads down, across the landscape after a fireball are not always easy to categorize. Some are focused on making money on what they find, but most are probably “meteorite enthusiasts, the true collectors who end up spending money on meteorites, not making it,” says Agee. However, some collectors are happy to sell when the opportunity arises, and meteorite dealers may also hunt.

We mused that the meteorite hunters could be the modern counterparts of the lone-wolf prospectors, who, with pick and mule, sought gold, silver and uranium in years past. Not so, says Slaughter. “There are handfuls of professionals, and they are very knowledgeable, and much more high-tech than the old prospectors.”

The hunters differ in another respect, says Slaughter. “I think it’s actually a much more social endeavor than the loner with his mule. You want to know who is looking where, what they are finding, how it compares to what you are finding.”

Meteorites land all over the place, Slaughter says, “so you need to know how to communicate in multiple languages, be aware of different legalities. Going up to the landowner and trying to get permission to look on the land is a surprisingly human exchange. When you are out looking with a team and you’re exhausted, dealing with that requires a human element.”

A surprising synergy

We went into this story wondering about a tension between the business of meteorites and the science of meteoritics, but we came out reassured. Are private collectors hiding meteorites from science? “I hear that rap in lots of areas: fossils, minerals and meteorites,” says Slaughter of the Wisconsin Geology Museum, “but I think actually in the meteorite world, scientists and collectors have worked out a mutually beneficial arrangement.”

The scientists who study meteorites often work at universities, and classes and students make it awkward to buy a ticket after a fireball has lit up some remote location. “Working with collectors is certainly the most cost-efficient way to get pieces,” says Slaughter, “and we don’t need very much to do the analysis, a few grams is usually a treasure trove.”

Agee, who is also professor of earth and planetary sciences at the University of New Mexico, agrees, “I have good interactions with collectors. Some of them put together really impressive collections that are on a par with museum collections, and often the collectors are keen to interact with the scientific community. A number of collectors I work with have donated to museums.”

But there are exceptions, Agee adds. “Like any business, you have people who are better citizens than others. It’s a reflection of the real world.”

“There are meteorite collectors who are every bit as zealous as those who collect art, prehistoric artifacts, or anything, really,” says Harvey. “When you have a fever for that kind of stuff, and part of the reason is financial, there are collectors out there — it’s a very small percentage — who, for lack of a better word, have bent the rules, had brushes with the law.”

Daddy’s meteorite

The publicity surrounding meteorites can actually pull samples off the woodwork, says Notkin. The “Sterley pallasite,” for example, sat for six decades on the family mantelpiece, but when it was analyzed at the Center for Meteorite Study at Arizona State University, it was recognized as one of only 86 known pallasite meteorites.

Photo by Suzanne Morrison © Aerolite Meteorites, LLC

The Sterley pallasite was discovered about 1950 by a Texas farmer, but was not classified or analyzed until 2012 when the finder’s family saw an episode of “Meteorite Men” on television. Pallasites are composed of approximately 50 percent nickel-iron and 50 percent olivine. Roll over photo for a detail of a full slice after preparation; the translucent areas are olivine crystals.

Notkin’s business, Aerolite, bought the meteorite, donated part to Arizona State, which had done the classification, and distributed parts to six researchers worldwide. “This meteorite turn out to be completely new and extremely rare, it’s one of the most beautiful ever found,” says Notkin.

The ability to contribute to significant research collections is a major motivation for amateurs, Notkin adds. “Amateur does not mean ignorant. In this scientific field, a lot of the most important contributions have been made by amateurs. As the word suggests, they do it for love, not for a stipend.”

Still, when it comes to the large, dramatic samples that museums want to grab eyeballs, the free market can impinge on short-budgeted university museums. Slaughter, for example, recently attended the Tucson Gem and Mineral Show, seeking a piece of a Martian meteorite, but the prices approached $1,000 per gram, and the University of Wisconsin Geology Museum had to decline.

At this point, the rising interest in the rocks arriving from space, among amateurs and professionals, is reinforcing our understanding of the evolution of the solar system. “We are about where the biology of natural selection was 200 years ago,” says Harvey. “Not too many years go by without the equivalent of another platypus coming along that does not fit our understanding of how meteorites relate to each other and to their parent body.”

Getting on the high road?

Do you love roads or hate them? If you’re an environmentalist, chances are you’re at least highly skeptical. Roads are famous for bringing settlers, forest destruction and farms to natural areas that are often inappropriate for sustainable agriculture.

But the agricultural industry, and people who promote farming as an antidote to hunger and poverty, see another side to roads. Farmers who want to do more than feed their families need good roads to bring in advisors, fertilizer and seeds, and take crops to market.

Roads that are muddy or impassable can make transport so expensive that cash cropping makes no sense.

This week, the journal Nature prints a proposal to square this circle by developing a system to chart where roads are beneficial, and where they are harmful. As the authors wrote, “We propose that environmental scientists, planners, road engineers and other stakeholders carry out a global ‘road-zoning’ project to map areas that should remain road-free and those in which transport urgently needs improving.”

We emailed corresponding author William Laurance, a conservation biologist at James Cook University in Australia, to ask if the idea was “pie in the sky.” Not so, he wrote. “What we’re hoping to see produced is a tool that anyone can use to prioritize where and where not to put roads. Some stakeholders and nations will hopefully use it, but of course not everyone will.”

Although rampant road-building in tropical forests has lead to significant forest destruction, “The situation is slowly improving,” Laurence wrote to us.  “Big highways tend to be more controlled than secondary and tertiary roads. Many of these smaller roads are being created illegally in remote areas, and that’s something that needs to be cracked down on.”

Roads really matter, says Lisa Naughton, a professor of geography at the University of Wisconsin-Madison, who studies development and conservation in the tropics. When the Interoceanic Highway was recently completed in the Peruvian Amazon, she says, “It utterly transformed the relationship between people, land and forests. The long-term efforts of Peruvian conservationists to promote sustainable agroforestry and non-timber forest-product harvest (such as Brazil nuts) were rapidly undermined as the road brought in large-scale agriculture, and deforestation has accelerated.”

Building in the zone

Rather than establish mandatory zoning, Laurance envisions a map that helps planners, politicians, agricultural interests and conservationists guide development while protecting indigenous lands, biodiversity hotspots and other sensitive areas.

The balanced approach, he says, “is a potential advantage … . We’re not saying to simply stop all road building. We’re saying let’s stop some of the environmentally destructive roads … while at the same time focusing road building where it’s likely to have the biggest economic and social benefits.”

According to projections, the demand for food will soar by 2050, due to a rising population with a growing desire for meat. According to the Laurance study, an extra 1 billion hectares (which happens to be the size of Canada!) will be needed for crops and grazing land. Much of that will have to take place on wild land.

But boosting agricultural productivity could supply some of this food, slowing the destruction of wild lands and wild creatures.

Roads: Farmers’ best friend?

It’s impossible to imagine advanced agriculture in developed countries without good roads. Do roads play the same role in developing nations? “It’s funny—this is one of those ideas that seems to be widely accepted but doesn’t have a lot of formal evidence,” wrote Laurance. “I know because we’ve looked. … In scientific terms, there is a scattering of papers and books that use econometric approaches to argue that road improvements benefit agriculture — reducing waste, increasing market access and improving profitability. But … there doesn’t seem to be much debate about this among those who study such things.”

Even if zoning for roads makes sense, practically speaking, could it work? Although national governments “have legal sovereignty over their lands, there are very powerful economic forces at work to promote road building — some of which are clearly inadvisable environmentally,” Laurance responded. The road-zoning scheme “could be used by governments and also conservation groups and other stakeholders to facilitate road planning.”

“The call for ecologically-informed road zoning is appropriate but faces major political challenges,” says Naughton, director of the Land Tenure Center at UW-Madison. “Perhaps some of the major roads funded by multi-lateral development agencies can be planned to lower social and biodiversity impacts. But there is ever more private and unilateral international funding available for road-building. More fundamentally, road-building has great political importance in a place like the Amazon — even if a road makes little economic sense, there are often strong political incentives to build it.”

But Laurance notes that, in the face of a proposal to push a road through a wilderness, “With a good road-zoning scheme, you could say, ‘Hold on a minute — that’s an environmental red-zone, the last place you’d want to construct a road. Let’s consider another route or perhaps even forego a new road altogether. Roads profoundly influence the spatial footprint of human activities, and so it’s crucial to focus explicitly on them.”