aquaculture-slideshow

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Discussion Questions

1.    What is the conservation dilemma at the heart of this article?  What is the “devil” referred to in the article’s title?

2.    Trace connections between Antarctic ice shelves, Everglades National Park, and the conservation of the Florida Panther.

3.    Why is the Florida Everglades a particularly important case study?  Can you think of other sites where the conflict between traditional approaches to conservation and restoration and newer ideas of “managed retreat” will be important to consider?

4.    In your own words, explain why sea levels may rise higher in North America than in other parts of the world. 

5.    What are some of the specific different ways that the inherent uncertainty of science influences conservation planning and decision-making related to predictions of sea level rise? 

Websites for Further Information

•    Congressional testimony of Everglades National Park Superintendent Dan Kimball on risks of sea level rise: http://www.nps.gov/ever/parknews/everclimatechangetestimony.htm

Sea Level Rise in the News

•    Sea’s rise may prove the greater in Northeast (New York Times, May 27, 2009): http://www.nytimes.com/2009/05/28/science/earth/28warming.html
•    Coral fossils suggest that sea level can rise rapidly (New York Times, April 15, 2009): http://www.nytimes.com/2009/04/16/science/earth/16coral.html

Key Concepts

•    Ecological restoration
•    Conservation planning
•    Climate change
•    Sea level rise

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Discussion Questions

1.    What are the crucial issues that must be addressed in order to make aquaculture more sustainable? How do the new approaches described here address these challenges? What issues remain to be solved?
2.    Will dilution solve the issue of pollution in aquaculture? What are some of the challenges of deep-water aquaculture?
3.    Do you think that we should use aquaculture to improve the supply and production of high-end fisheries products, or should we focus on improving aquaculture that would benefit lower income people who may depend upon oceans for the majority of their protein needs? Can we address both simultaneously?

Websites for Further Information

•    NOAA Aquaculture Program: http://aquaculture.noaa.gov/
•    NOAA Central Library, Aquaculture Information Center: http://www.lib.noaa.gov/docaqua/frontpage.htm
•    World Aquaculture Society: https://www.was.org/Main/Default.asp

Aquaculture in the News

•    Obama administration hands offshore aquaculture oversight to NOAA (New York Times, April 23, 2009): http://www.nytimes.com/gwire/2009/04/23/23greenwire-obama-admin-hands-offshore-aquaculture-oversig-10648.html?scp=1&sq=aquaculture&st=cse
•    In China, Farming Fish in Toxic Waters (New York Times, December 15, 2007): http://www.nytimes.com/2007/12/15/world/asia/15fish.html
•    When Fish Farms Are Built Along The Coast, Where Does The Waste Go? (ScienceDaily, Feb. 25, 2009): http://www.sciencedaily.com/releases/2009/02/090215151758.htm
•    Aquaculture’s Growth Seen As Continuing (ScienceDaily, Jan. 9, 2009): http://www.sciencedaily.com/releases/2009/01/090102082248.htm

Peer-reviewed Literature (in addition to the citations listed in the article)

•    Cressy, D. 2009. Future fish. Nature 458: 398-400.
•    Brander, K.M. 2007. Climate change and food security: Global fish production and climate change. Proceedings of the National Academy of Sciences  104: 19709-19714.
•    Neori, A., M. Troell, T. Chopin, C. Yarish, A. Critchley, and A.H. Buschmann. 2007. The need for a balanced ecosystem approach to blue revolution aquaculture. Environment: Science and Policy for Sustainable Development 49: 36-43.

     
Key Concepts

•    Ecosystem health
•    Deep water aquaculture
•    Integrated multitrophic management

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Discussion Questions

1.    What fundamental conflict of ideals within the environmental community does this article address? After reading the article, do you feel that human energy sustainability will be achieved only at a further cost to biodiversity, or do you feel that there is a solution to benefit both? Is one side of the “green” movement blind to the needs of the other? How does biodiversity conservation rank in terms of priority for the new “green” economy?

2.    What do you think of Tilman’s idea that prairies could produce more than double the bioenergy compared to traditional agriculture, and thus may accomplish both biodiversity conservation and biofuels production? Refer to the first box in the article and Tilman et al.’s 2006 Science paper for more specific information.

3.    What is cellulosic biofuel? How might it deliver more energy, with less harm to the environment? What are some potential waste sources for the energy? We have a United States Presidential administration that is clearly in favor of seeking alternative energy sources and ending dependence on fossil fuels (see web link below). What kind of priority setting do you think this administration has done in terms of other environmental concerns?

4.    How much land may be required to bring the portion of the world’s energy provided by cellulosic fuels to 10%, and where on the planet would be the hardest hit? What role might marginal lands play in mitigating these effects on wild biodiversity?

5.    What tradeoffs in your own life can you envision that involve balancing your need for energy with your concern for wild plants, animals, and the landscapes in which they exist? Having read this article, do you feel that biofuels are a solution for global climate change and the world’s energy problems? Or do you sense that if humans don’t drastically reduce energy demand we are facing an even greater biodiversity crisis than the one we have now? As a student, how can you make a difference?

Websites for Further Information

•    The White House Energy and Environment page: http://www.whitehouse.gov/issues/energy_and_environment/
•    Cellulosic fuel production: http://en.wikipedia.org/wiki/Cellulosic_ethanol
•    Dr. David Tilman’s webpage at the University of Minnesota with bibliography of his research on biofuels: http://www.cbs.umn.edu/eeb/faculty/TilmanDavid/

Biofuels in the News

•    Ethanol’s grocery  bill  (Wall Street Journal, June 3, 2009): http://online.wsj.com/article/SB124389966385274413.html
•    Brazil to invest in ethanol workers, environment (Guardian, June 1, 2009): http://www.guardian.co.uk/business/feedarticle/8536248

Peer-reviewed Literature (in addition to the citations listed in the article)

•    Fargione, J., J. Hill, D. Tilman, S. Polasky and P. Hawthorne. 2008. Land clearing and the biofuel carbon debt. Science 319: 1235-1238. 
•    Koh, L.P. 2007. Potential habitat and biodiversity losses from intensified biodiesel feedstock production. Conservation Biology 21: 1373-1375.
•    Groom, M.J., E.M. Gray, and P.A. Townsend 2008. Biofuels and biodiversity: principles for creating better policies. Conservation Biology 22: 602-609.

Key Concepts

•    Tradeoffs, energy and environment
•    Biofuel
•    Energy production
•    Energy sustainability
•    Climate change

Courtesy of the MIT Sea Grant College Program

Cliff Goudey from the Massachusetts Institute of Technology is developing a self-propelled fish cage. Mobile aquatic farms prevent buildup of concentrated fish waste and save energy now used by the towboats that haul commercial fish pens. Above is footage from a trial run of the mobile pod. Read more about innovative ideas in aquaculture in Sarah Simpson’s feature article.

In the 1960s, while working at the Jet Propulsion Laboratory, British scientist James Lovelock introduced the Gaia hypothesis, positing that Earth is a self-regulating system made up of both biotic (life forms) and abiotic (air, ocean, and surface rocks) components. In the 1970s, as a result of his collaboration with American scientist Lynn Margulis, the hypothesis gained strength. In the 1980s, as confirmatory evidence and mathematical models emerged, the concept became Gaia theory.

From: The Vanishing Face of Gaia by James Lovelock. Excerpted by arrangement with Basic Books, a member of the Perseus Books Group. ©2009.

The Natures of Maps:
Cartographic Constructions of the Natural World
By Denis Wood & John Fels
University of Chicago Press, 2008

Maps, argue Denis Wood and John Fels, aren’t representations of reality so much as they are sets of arguments. Behind every map is a cartographer with a purpose and an agenda. Although we might presume maps of the natural world—topographic maps, vegetation maps, maps of bird migrations—to be scientific and objective, these presumptions fall apart under Fels and Wood’s scrutiny. They show how every element of a map—from the way it is folded to the text in the legend to the ink colors used—shapes how we see nature: either as threatened or as a threat, as something we can possess or as a mystery. ❧

American Buffalo:
In Search of a Lost Icon
By Steven Rinella
Doubleday, 2008

In 2005, Steven Rinella won one of 25 permits to hunt buffalo in the Alaskan wilderness. His adventure took him trekking through frigid conditions while evading grizzly bears and hauling a 1,000-pound carcass over mountains and down a river. But this was only part of a quest that started after Rinella came across a buffalo skull while hiking in Montana. He also traveled the United States to document the buffalo’s historic, cultural, and natural significance over thousands of years. American Buffalo chronicles both the author’s personal adventures in the wild as well as the history of an animal that has made an impressive recovery after being hunted almost to extinction. ❧

The Life of the Skies:
Birding at the End of Nature
By Jonathan Rosen
Picador Press, 2008

As birds become the only wild animals left in our urban landscapes, Jonathan Rosen’s book is a philosophical musing about the place birding holds in the modern world. Bird watching allows us to enter into the wild world—but only while engaged in the uniquely human activities of identifying, naming, and cataloguing. This intersection of civilization and nature is a central theme of Rosen’s book, and the novelist and literary critic explores it through references to Whitman, Keats, Hemingway, and others. ❧

Swimming with Piranhas
at Feeding Time:
My Life Doing Dumb Stuff with Animals
By Richard Conniff
W.W. Norton & Co., 2009

Richard Conniff writes for Smithsonian
and National Geographic and has traveled from Botswana to Louisiana to Costa Rica covering wildlife and nature stories. His new book is a collection of animal anecdotes from around the world. When not swimming in a tank of piranhas, Conniff observes the sex lives of dung beetles (prone to infidelity), describes termites who share food “from both ends of the digestive tract,” and considers paternity questions in cheetah society.

The Global Deal:
Climate Change and the Creation of
a New Era of Progress and Prosperity
By Nicholas Stern
Public Affairs, 2009

Nicholas Stern’s book is a blueprint of how governments across the world can reduce emissions while ushering in a new age of growth and prosperity. He calls for international agreements on an unprecedented scale and argues that cooperation is our only option for facing the challenges of global warming. Stern’s 2006 report on the economics of climate change was read worldwide and remains one of the most influential analyses of its kind. Although tempered, the book is one of the more optimistic pieces to emerge from the climate change discussion. ❧

Eco Barons: The Dreamers, Schemers, and Millionaires Who Are Saving Our Planet
By Edward Humes, Ecco Press 2009.
Review by Florence Williams

How important are individuals to social change? The question has been a topic of lively debate since at least the Enlightenment. In Eco Barons: The Dreamers, Schemers, and Millionaires Who Are Saving Our Planet, Edward Humes clearly believes the answer is that passionate citizens, often acting outside of institutions, play a critical role in leading us toward a greener future. This optimistic belief is enticing, especially at a time when many people have pinned hopes on the strong and ambitious personality now occupying the White House. But the traits enabling the individuals profiled by Humes to act heroically lead some to regard them as villains—or at least megalomaniacs— and how they navigate this conflict can have serious consequences for conservation.

Certainly, Humes’s heroes are inspiring and effective. They’re saving vast swaths of ancient forests and the biodiversity contained therein. They’re influencing climate policy, confronting large corporations (in some cases after having benefited from similar ones), rethinking the internal combustion engine, and educating a generation of school children. Take Doug Tompkins, a scrappy rock climber who founded the North Face and Esprit clothing companies, turned Madison Avenue on its head by injecting real people into fashion advertising, and eventually sold the firms for hundreds of millions of dollars. Humes chronicles how Tompkins used this fortune to buy up vast expanses of land to establish nature reserves in Chile and Argentina. The book also details how Roxanne Quimby (cofounder of lip-balm empire Burt’s Bees) and CNN magnate Ted Turner adopted similar buy-it-myself land-preservation crusades.

Humes fawningly attributes his heroes’ accomplishments to their passion and ambition but glosses over other personality traits they share: outsized egos, an extreme propensity toward risk-taking, and a pretty fundamental disregard for the opinions of others. Unfortunately, Humes never explores the irony encased within his coinage “eco-barons.” Taking on giant corporations (and local employers), battling governments, and imposing environmental values on people who aren’t necessarily inclined toward them can be a messy affair. It can heighten class warfare, escalate political tension, and jeopardize—or at least delay—conservation goals. Tompkins, who’s never been keen on social graces, managed to insult or offend much of Chile—some locals think the strict rules governing his lands violate Chilean sovereignty, and the Chilean government actually blocked one of his land purchases in the late 1990s. Turner and Kieran Suckling (founder of the confrontational Center for Biological Diversity) were cut from the same to-hell-with-what-anyone-else-thinks cloth in their quests to protect endangered species at the peril of local, rural economies.

There’s a place for this approach to conservation, but Humes could have better examined his subjects’ bouts of misanthropy and the ensuing damage. It’s a shame he doesn’t dig deeper into the psychological traits that cause some barons to know not only when to get into fights but also how to get out of them. When it comes to conservation, knowing when to clobber the opposition and when to collaborate is a critical skill. To his credit, Humes does celebrate the effective, compromising path ultimately taken by Quimby. Like Tompkins and Turner, she wanted to save the wilderness from the ravages of development and had the money to do it. After buying large landholdings in Maine’s North Woods and banning traditional uses such as snowmobiling, hunting, and logging, she became the target of local residents, who took to sporting bumper stickers that read “Ban Roxanne.” Quimby soon realized she could better advance her interests by working with people, not against them. It’s a good lesson for other would-be eco barons. ❧

It’s common knowledge that animals are reluctant to walk across highways and that this can block migrations and dilute gene pools. Researchers have now discovered that some critters—in this case, a species of bat—won’t fly over busy roads. Strangely, the bats will happily cross beneath the roads, and researchers hope to build bat tunnels throughout Europe to facilitate their migration.

The discovery was made by Gerald Kerth of the University of Zürich. Kerth monitored two bat species and found that Barbastelle bats, which typically fly high in the air, traveled unfettered across a highway. Bechstein’s bats, which fly and hunt at ground level, refused to travel over the road, perhaps because traffic noise or bright lights scared them off.

However, three of the Bechstein’s bats did make an unlikely crossing by darting through underpasses. Kerth suspects the bats stumble upon the passages, which are quieter than the road, while looking for food or a place to hang. They will use an underpass repeatedly once they know it exists.

Kerth proposes building dozens of specially designed bat tunnels, spaced one to two kilometers apart, to help bats access a wider array of feeding grounds and nesting sites. He recommends the tunnels be at least three meters in diameter and that vegetation connect them to the forests, making them easy for bats to find. ❧ —John Weier

Story by Sarah Simpson
Illustration by Ira Korman April-June 2009

A shipment of 100,000 fresh, sushi-grade cobia, each fish amounting to about five pounds of firm, white meat, arrives on schedule in the Port of Miami. In this case, “fresh” does not mean beheaded and ice-packed—these fish are very much alive and swimming. As fingerlings, they were set adrift in a 3-million-liter pen which latched onto a current traveling the Caribbean in a predictable, clockwise path. Nine months later, a frenzy of splashes erupts at the water’s surface as the underwater corral emerges from the depths. After rounding the western tip of Cuba and skirting a storm near the Yucatán (via remotely operated thrusters), the floating farm has made port just as the fish reach harvestable size.

Aquatic engineer Clifford Goudey had this futuristic vision dancing in his head last July when he tested the world’s first self-propelled, submersible fish pen. A geodesic sphere measuring 19 meters in diameter, the cage proved surprisingly maneuverable when outfitted with a pair of 2.5-meter propellers, says Goudey, who directs MIT Sea Grant’s Offshore Aquaculture Engineering Center. In his Caribbean current scenario, Goudey imagines launching dozens of floating farms in a steady progression, each a week behind the other. His work marks a breakthrough in the quest to raise fish in parts of the oceans that are too deep for traditional, anchored cages. It also amounts to a key step toward what a few cutting-edge thinkers have been craving for years: the wholesale taming of the sea.

The oceans provide about 20 percent of the world’s protein, and pressure to deliver this critical food stream has led to extreme overharvesting. As wild fish stocks decline, aquaculture is the logical candidate to pick up the slack, and some are looking to it as a way to rebuild commercial fish stocks. In a 2005 Nature commentary, oceanographer John Marra argued that widespread ocean farming is inevitable. “We have already accepted domestication of the land,” Marra wrote. “Now is the time to accept the same for the seas.” (1)

Such visions have long been anathema to many environmentalists who fear the spread of present-day aquaculture’s myriad ills. Many of today’s coastal fish farms have decimated habitat and spread disease into local fish populations. Making matters worse, fish farms represent a net drain on populations of wild fish, which are often caught just so they can be ground into feed for salmon and other species.

Despite these concerns, a shift is underway. Some members of the environmental community are concluding that widespread aquaculture must be pursued if we are to save the oceans and feed the planet. Aquaculture production must double by 2050 just to keep up with per capita demand. But merely scaling up current methods would only exacerbate the problems.

In other words, the world needs new, sustainable aquaculture practices, and it needs them fast. It took 10,000 years for domestic agriculture to transform the land, but viable ocean farming schemes must be developed in one one-hundredth of that time if they are to forestall the oceans’ demise. This urgency is spurring some leading environmentalists and scientists to lend their knowledge and support, instead of their opposition. In a recent lecture, the renowned marine ecologist Jeremy Jackson discussed the threat of overfishing and announced, “the most important scientific challenge we now face is how to make aquaculture ecologically sustainable.”

The mobile fish pens are just one example of the cutting-edge technologies emerging to surmount Jackson’s challenge. Also in the works are intriguing methods of recycling fish sewage, new feed formulations that use dramatically smaller amounts of wild fish, and onshore farms where salt-water species are tricked into living in fresh water. As these developments solve some of aquaculture’s seemingly intractable problems, they could also be the first steps toward widespread, sustainable domestication of the oceans.

From his post at eastern Canada’s Bay of Fundy, Thierry Chopin has seen first-hand how salmon farms devastate bays and inlets. Typically located just a stone’s throw from shore, the farms are relentless sources of excrement and pollution. Some estimates suggest the nutrient outfall from salmon farms in Scotland, for example, is comparable in volume to the untreated sewage from half its human population. What’s more, salmon are sloppy eaters that typically consume only about 80 percent of the food that comes their way. The nutrient-laden effluent spills from cages, sometimes triggering harmful algal blooms and other pollution problems. But Chopin, a University of New Brunswick marine biologist who has spent eight years trying to mitigate these problems, says cleaning up salmon farms may be as simple as re-casting poop and uneaten food scraps as a resource.

In conjunction with Cooke Aquaculture, a Canadian company pursuing sustainable farming, Chopin is experimenting with so-called integrated multitrophic aquaculture, or integrated farms. This innovative approach positions salmon pens in close proximity to plants and animals that actually consume the pollution. The farms aim to absorb the vast majority of the salmon waste, sparing the surrounding waters while nurturing species that can be sold on the global seafood market.

Seen from above, Chopin’s operation looks like a tray of soda cans, with circular salmon pens anchored in a square grid. It amounts to a carefully calibrated ecosystem, and Chopin, along with Shawn Robinson at Canada’s Department of Fisheries and Oceans, has helped identify which species can thrive within it. “It’s all about choosing species based on their function,” Chopin explains.

Seaweeds, for instance, are amazingly efficient waste recyclers that can extract about 40 percent of the dissolved nutrients available during their growing season. To take advantage of this, Chopin’s team positions seaweed on ropes dangling from rafts located downstream from the pens. The kelp thrive in this fertilizer bath, which is primarily ammonia released from salmon gills and decaying food pellets; some species grow as much as 46 percent faster than they do in salmon-free areas.

Sharing the same grisly appetite for salmon waste are filter-feeding mussels, which play a different role in the clean-up process by extracting particles of excrement and food scraps. Chopin’s system places the mussels in cages alongside the fish pens. Thanks to their close quarters with salmon, the mussels grow as much as 50 percent faster as they absorb about half of the fine waste particles. About three years ago, though, Chopin’s team realized some waste particles were too big for the mussels to manage. That’s where sea cucumbers and urchins, which thrive on the heftier scraps and are placed in trays directly below the salmon pens, come into the picture. “One man’s trash is another’s treasure” takes on new meaning when you see how remarkably plump a culinary delicacy such as urchin roe grows in a cloud of salmon sewage.

There is, of course, a more obvious way to manage the effluent problem: move fish farms away from the coast, into deeper waters where pollution would be carried off and diluted by the sea. That turns out to be much harder than it sounds. For starters, offshore cages have to be built to withstand the pressure and currents that come with being located farther out at sea—keeping enormous pens steady in 60 meters of open water is a tricky proposition. They must also keep their plump inhabitants safe from sharks and other predators looking for an easy lunch.

A handful of companies are overcoming these challenges with innovative cage designs that allow fish to be farmed in deeper water than ever before. Anchored varieties of the spherical AquaPod, developed by Ocean Farm Technologies in Searsmont, Maine, range up to 27 meters in diameter, which translates to almost a billion liters in capacity. Another innovator is Bainbridge Island, Washington­–based OceanSpar, which has developed its SeaStation pens in the shape of oversized toy tops. Built around galvanized steel frames, the pens are covered in Kevlar-like netting that prevents wily fish from chewing their way out—or in.

Half a mile off the Hawaiian coast, Kona Blue Water Farms is using eight 3-million-liter SeaStations to house some 480,000 Hawaiian yellowtail. The pens are tethered by a network of 22 anchors, each weighing 3.5 tons and anchored by a one-ton chain. All told, Kona Blue spent around $500,000 to set up the infrastructure 30 meters beneath the sea (except during maintenance and harvest), which allows excrement and uneaten food to be swept away in brisk subsurface currents. Water quality downstream from the pens is the same as at sites upstream. The innovations deliver a glimpse of the future, when industrial techniques may transform the continental shelf into a sprawling network of farms playing a vital role in global food production.

Neil Sims, cofounder of Kona Blue Water Farms, is taking aim at another critical hurdle to sustainability: the need to harvest vast amounts of wild fish just to feed the ones being farmed. Salmon and other carnivorous fish must be fed large quantities of fish oil and fish meal to gain the taste and texture that consumers crave. It typically takes 2.3 kilograms of so-called “forage fish” to produce half a kilogram of farmed fish. (And that’s using carefully formulated feed pellets; many fish farms around the world still use raw fish, which pushes the necessary kilograms to nine or higher.) Fortunately, Sims is gaining ground in his crusade to rewrite this equation.

Sims oversees a booming operation that produces one of the world’s most prized farmed fish: Hawaiian yellowtail sold under the name Kona Kampachi. Sold in swank restaurants across the U.S., a serving of Kona Kampachi sashimi can fetch a price upwards of $15, in part because sushi connoisseurs prize the fish’s firm, yet tender, flesh. Sims worries that, as aquaculture grows, it will further harm the species that form the basis of fishmeal. In the past 25 years, farming of marine fish and shellfish has grown by 10 percent per year. That surge translates into ever-increasing pressure on populations of forage fish such as anchovies and sardines. So Sims has launched an ambitious effort find replacement sources for the fatty acids and amino acids his fish need.

When Kona Blue anchored its first offshore pen in 2005, their feed was 80 percent Peruvian anchovy fishmeal and fish oil. By early 2008, the company had reduced that percentage to 30, thanks to careful experimentation that allowed Kona Blue to substitute soybean meal and chicken oil for the fish products. Sims is thrilled to say it now takes only 1.4 kilograms of Peruvian anchovies to produce one kilo of Kona Kampachi. Indeed, this breakthrough—in combination with Kona Blue’s other conscientious practices—made U.S.–farmed yellowtail the first ocean-farmed fish to earn a “good alternative” rating from Seafood Watch, Monterey Bay Aquarium’s popular sustainable seafood advisory list.

Sims acknowledges the battle is ongoing and Kona Blue is aggressively pursuing a 1:1 ratio. To achieve this, the company is looking at soy protein concentrates as well as canola and soy oils. Kona Blue is also keeping an eye on a particularly exciting biotech breakthrough in which scientists have coaxed the coveted omega-3 fatty acid DHA out of microscopic algae. One animal-nutrition firm is now testing fish feeds enhanced with the same algal-based DHA already marketed in infant formula, milk, and juice.

Sims isn’t alone. Similar feed formulations have been developed for cobia and other fish, but the limiting factor is cost. Until the price of fish meal and fish oil rise to reflect the world’s depleted stocks, Sims says, it will be hard for many aquaculturists to justify pricier, more sustainable feed.

Even those at aquaculture’s leading edge have difficulty predicting just how quickly the new practices might translate into large-scale ocean domestication. But they do agree that difficult barriers remain and that the biggest challenges may be not technical but political.

Take Goudey’s self-propelled AquaPod. Sending flotillas of corralled fish to fatten up on the high seas is already feasible from an engineering standpoint, he says. A first step might be free-floating farms riding in and out and back again with the tide, returning to the same spot every 12 hours. Eventually, Goudey envisions full transoceanic voyages: penned fingerlings launched from Miami hitch a ride on the Gulf Stream to Europe, where they are harvested and replaced with a new, young brood for the return voyage to America. It would require only the integration of the self-propelled cage (such as the one he tested last summer) with a surface buoy carrying an automatic feeder (imagine a giant version of what you leave for your cat when you go on vacation)—plus navigation, tracking, and communications networks such as those already well-honed for research submersibles and Mars rovers.

Even though the technologies are within reach, progress toward offshore farming has been sluggish. Of some 50 offshore installations worldwide, only five U.S. commercial marine fish and shellfish farms have ventured into open water. Goudey thinks more aquaculture entrepreneurs would jump into the fray if the U.S. put into place the appropriate legislation and permitting systems. This would not only give aquaculturists the green light but also help guide the industry toward a sustainable future. Introduced in 2007, the National Offshore Aquaculture Act, for instance, would have authorized the U.S. government to grant aquaculture permits throughout the U.S.–exclusive economic zone, which extends 200 nautical miles from each coast. Issuance of these permits could be tied to sustainable practices. But the legislation has languished in Congress since 2005 and has not been reintroduced this session.

That reality has forced at least two U.S. offshore fish farms, frustrated with the permitting chokehold, to investigate expanding their operations to Mexico and Panama—or move them there entirely. In other words, businesses that might be goaded into pursuing sustainable aims via legislation now have incentives to migrate to other waters where the aquaculture mentality might be more akin to “anything goes.”

Halting such overseas moves would also give the U.S. opportunity to improve food security. Among natural resources, the country’s $9 billion annual trade deficit in seafood is second only to its dependence on foreign oil. To help offset that food imbalance, the U.S. Department of Commerce has declared it would like to quintuple the value of annual domestic aquaculture production, currently just shy of $1 billion, by 2025.

If the world can muster the unprecedented political will and international cooperation necessary to domesticate the high seas, critics ask, why not put those energies toward restoring the oceans rather than risk degrading them further? As Julia K. Baum wrote in Nature in reply to Marra’s 2005 call to tame the seas, offshore aquaculture “is not ‘inevitable.’ It is a course of action that can be chosen—or not.” (2)

Given the world’s food needs, such a wholesale rejection of aquaculture might amount to accepting the status quo: a fishing industry that is devastating wild stocks, decimating the oceans, and generating enormous amounts of CO2. As Scripps’s Jeremy Jackson points out, “sustainable fishing is an oxymoron.” Jackson draws a comparison to hunting and gathering and argues that sending flotillas of fishing boats out to round up wild fish is on a par with hunting down bears and elk for food. “If we’re going to get lots of protein from the ocean,” he concludes, “the only solution is aquaculture.”

That doesn’t mean today’s latest methods are the final solution. After all, farmed yellowtail and salmon, like cod and tuna, are luxury foods that most people in the world will never taste. Together with academics such as Stanford University’s Rosamond Naylor, Jackson believes we won’t be able to save the oceans until we abandon our taste for fish that live high on the food chain. In that case, the world’s ocean-based protein would have to come from anchovies, shellfish, and other species operating at lower trophic levels.

From this point of view, the latest aquaculture innovations are best seen as an incomplete step in an important direction. Perhaps offshore farming will ultimately provide all the high-trophic-level species the world demands and also mass-produce the species many environmentalists find more favorable. Free-floating farms, for instance, could also be used to grow sardines, Goudey says. The University of New Brunswick’s Chopin adds his own twist to the idea: he would add shellfish and seaweed rafts trailing behind.

As we pursue these goals, Chopin reminds us to be patient and to understand that a rapid transition to aquaculture means there will be missteps along the way. “Even after centuries of agriculture, we don’t have all the best practices,” he says. “In aquaculture, we want to solve everything in a few decades.” ❧

Literature Cited:

1. Marra, J. 2005. When will we tame the oceans? Nature 436:175–176.

2. Baum, J., J. McPherson, and R. Myers. 2005. Farming need not replace fishing if stocks are rebuilt. Nature 437:26.

Further Reading:

Halweil, B. 2008. Farming fish for the future. Worldwatch Report 176. Eagle, J., R. Naylor, and W. Smith. 2004. Why farm salmon outcompete fishery salmon. Marine Policy. 28(3):259–270.

Michler-Cieluch, T., G. Krause, and B.H. Buck. 2009. Reflections on integrating operation and maintenance activities of offshore wind farms and mariculture. Ocean & Coastal Management 52:57–68.

Story by David Malakoff
Illustration by Randy Lyhus
April-June 2009

These days, Jason Clay walks around with an eerie sense of déjà vu. Over the past few years, the World Wildlife Fund (WWF) anthropologist has become deeply entangled in the tortuous struggle to ensure that supposedly “green” biofuels—such as ethanol brewed from corn and biodiesel wrung from palm nuts—don’t decimate biodiversity in an attempt to save the planet. It’s been a dizzying and sometimes disorienting experience. For instance, Clay watched as biofuels, once hailed as the savior of the climate, became an environmental sinner almost overnight—blamed for everything from food riots to trashed tropical forests. “The backlash has been pretty ferocious—ethanol and biodiesel have lost a lot of their green image,” he says.

Now Clay is bracing for what could be an even more jarring roller-coaster ride. Some scientists, executives and political leaders—including President Barak Obama’s energy team—are touting a new breed of “cellulosic” biofuels. They argue that these second-generation fuels—created by breaking down cellulose, the molecule that gives trees and grasses their toughness—could deliver more help with less harm. Some even paint the picture of a future powered by waste sawdust, grass clippings and corn husks. And they are dreaming big: by 2022, the United States alone could brew more than 75 billion liters of cellulosic ethanol a year. Experts say that will require spending tens of billions of dollars on research and corporate subsidies and dedicating tens of millions of hectares of land to producing biomass, from hay bales to whole logs.

The dream of cellulosic ethanol, however, is causing nightmares for many ecologists. They fear that growing demand for cheap, ample supplies of cellulose will create powerful incentives to convert diverse, native grasslands into sterile “energy lawns” and to simply chop down vast swaths of wild forests. Even if these environmental costs are mitigated, it’s getting harder to identify the upside of cellulosic fuels—a recent MIT study suggests that, despite the hype, the new fuels may not reduce overall greenhouse-gas emissions. Which raises an unsettling question: can the pursuit of clean, “green” fuels lead to a true ecological solution, or is it just a detour from traditional conservation strategies that, although less futuristic, might be far more effective?

New research is crystallizing fears that cellulosic fuels might wreak havoc on the world’s landscapes. Forecasting what will happen if the fuels take off is a tricky enterprise because biofuels can have indirect effects that ripple around the globe. If a farmer in Europe, for instance, replaces the soybean crop she sells to China with an energy crop such as switchgrass, it could create an incentive for a farmer in South America to clear a new chunk of forest or grassland to replace the European soybeans. Similarly, a move to log a forest in Siberia for energy cellulose could put added pressure on Asian or African forests to produce plywood or lumber for the housing market.

In January, a team at the Massachusetts Institute of Technology (MIT) released one of the most ambitious efforts yet to make sense of it all. Led by climate specialist Jerry Mellilo of MIT and the Marine Biological Laboratory in Woods Hole, the team used a complex computer model to produce a vision of the global landscape in 2050.

After assuming that cellulosic fuels provide at least 10 percent of the world’s energy supply, the study concludes that “large tracts of natural forests, woodlands, and grasslands will be converted to either food or cellulosic biofuels production.” By 2050, the land devoted to cellulosic crops mushrooms to about 11 percent of the earth’s total (between 13.9 and 14.8 million square kilometers). Many areas would lose from 20 to 70 percent of their natural habitats, with tropical and semitropical ecosystems able to produce high levels of biomass the hardest hit. On the lengthy danger list: biodiversity “hotspots” in Mesoamerica, the cerrado of Brazil, Guinea/West Africa, Madagascar, Indo-Burma, and the cluster of Philippines, Malaysia, and Indonesia.

In part, that list reflects the expectation that “forests in the tropics could get hit particularly hard by cellulosic ethanol,” says James Bowyer, a forestry industry expert with Dovetail Partners, a nonprofit environmental consulting group in Minneapolis, Minnesota. That’s because natural forests would provide a relatively cheap, easy-to-exploit supply of cellulose. And unlike grasses that must be harvested and carefully stored, “trees are easy biomass to store when they aren’t needed,” says Bowyer. “You just leave them standing in the forest when the market dips, and wait for ethanol prices to rebound.”

Ironically, the MIT team concludes it’s not clear that the profound transformation in land use spurred by cellulosic ethanol would actually reduce greenhouse-gas emissions. In part, that’s because clearing new land can release carbon stored in soil and plants, negating the benefits of using the biofuels to replace fossil fuels. In fact, the land-use changes wreaked by use of cellulosic biofuels would add carbon to the atmosphere in the first half of the twenty-first century. Even under the most optimistic scenario, it would take some 50 years for the use of cellulosic biofuels to offset that added carbon.

Cellulosic fuels advocates say such problems can at least be reduced by planting biofuel crops on so-called marginal lands that have already been plowed, grazed, or logged. But here, too, scale is an issue. A February 2009 study by the Department of Energy’s Sandia National Laboratory and General Motors’ R&D Center, for instance, suggests it could take at least 20 million hectares of currently “idle” or “marginal” U.S. farmlands and forests to grow the biomass needed to produce 170 billion liters of cellulosic fuel a year by 2030. That means putting an area the size of Kansas into cultivation, a feat that could exact a stiff toll on biodiversity.

“You hear a lot about using ‘marginal lands’ and ‘waste wood,’ but that land and debris is still somebody’s habitat,” says Doug Landis, an ecological entomologist at Michigan State University. And in grasslands, “even a degraded prairie or hayfield can be better for biodiversity than planting a switchgrass monoculture,” notes grassland ecologist Mike Palmer of Oklahoma State University.

Still, to gain standing in the biofuels policy debate, ecologists are ramping up an array of studies that, in the words of one, “once again will prove the obvious”: that prairies and other multispecies ecosystems requiring few inputs such as irrigation and fertilizer are often better for biodiversity and overall environmental functioning than high-input, low-diversity systems such as corn fields.

For instance, Mary Gardiner, a post-doc with Landis, has started intensively studying 30 sites across southern Michigan that might produce biofuel crops. They range from low-diversity corn fields to switchgrass plots to remnant prairies. Not surprisingly, Landis says, preliminary results suggest that the corn mono-cultures support less insect diversity than the lower-input switchgrass and prairie plots. Other researchers are documenting similar trends in birdlife, with the prairies providing more nesting and feeding habitat. Overall, it appears “prairie gives you the most diversity—and it may be able to produce just as much usable biomass too,” he says. Indeed, some scientists say “energy prairies” could be one way to both fight climate change and promote biodiversity.

Other researchers, such as plant ecologist Linda Wallace of the University of Oklahoma in Norman, are pondering the implications of replacing even degraded grasslands with switchgrass and other fast-growing plants. One problem, Wallace says, is that studies show switchgrass or other perennial grasses can become highly invasive in some places, “so the ecological footprint is much larger than the field.”

The problems with cellulosic fuels seem depressingly familiar to WWF’s Jason Clay and other veterans of the first biofuel war. “It seems like the same arguments are coming up, just in a new context,” Clay says. And until it is clear exactly how cellulosic technologies will play out—and whether any will become economically viable—he predicts the discussions will be frustrating and sometimes baffling. To help unmuddy the waters, WWF and other groups have been contributing to efforts to measure the impacts of cellulosic fuels and develop guidelines for “sustainable” production.

But the closer you look at the debate, the harder it becomes to ignore a conclusion reached by many analysts of the bioenergy conundrum: to make biofuels—or any fuels—truly environmentally friendly, we may simply have to use them in smaller quantities. Which means it might be time to further embrace age-old solutions such as developing fuel-efficient vehicles, switching to a diet that substitutes vegetables for meat, building a highly efficient distribution infrastructure. The list goes on—and, like the latest biofuels controversy, it’s all too familiar. ❧

Literature Cited:
1. Tilman, D., J. Hill, and C. Lehman. 2006. Carbon-negative biofuels from low-input high-diversity grassland biomass. Science 314:1598–1600.
2. Schmer, M.R. et al. 2008. Net energy of cellulosic ethanol from switchgrass. Proceedings of the National Academy of Sciences 105:464–469.
3. Purdon, M., S. Bailey-Stamler, and R. Samson. 2009. Better bioenergy: Rather than picking bioenergy “winners,” effective policy should let a lifecycle analysis decide. Alternatives Journal 35:23-29.

David Malakoff is a science writer based in Alexandria, Virginia.

The more they look, the more scientists discover that the benefits of shade-grown coffee extend far beyond its robust flavor. Instead of leveling the forests, shade coffee farms leave a canopy of trees intact and grow plants beneath them. The farms have been shown to provide critical habitat to a variety of animals, including bats, birds, and pollinating insects. Now a study in Current Biology finds they could also play a key role in ravaged forests’ recovery.

The finding comes from Chiapas, Mexico, where University of Michigan biologists Shalene Jha and Christopher Dick studied a patch of uncut forest surrounded by shade-coffee plantations.The researchers wanted to know whether the plantations affected how seeds of a particular type of tree, Miconia affinis, were dispersed.

To answer this, the biologists looked at whether Miconia trees situated near each other tended to be closer relatives than Miconia trees spread farther apart. The clustering of closely related trees, which occurs when seeds mostly remain near the tree that produced them, is common in tropical forests. This is often due to the constrained foraging ranges of the birds specifically adapted to that section of forest; the birds don’t roam far enough to distribute seeds beyond a narrow radius. This is magnified as forest patches become smaller and more isolated, until inbreeding among trees causes their populations to decline.

Sure enough, the Miconia in the patch of native forest showed a pattern of genetic relatedness. But in a striking contrast, no such pattern was seen among Miconia that had spread throughout the shade coffee plantations over the past half-century.

In these areas, the researchers believe, a larger variety of bird species scattered seeds of different Miconia lineages over a broad area, ensuring a genetically diverse population. The authors conclude that, by conserving native birds, shade coffee farms harbor a mechanism for seed dispersal that may be essential for the conservation of trees. By maintaining gene flow and, in turn, the genetic diversity of native trees, the farms could eventually help tropical forests regenerate. ❧
—Scott Norris

Story by Jim Robbins
Illustration by Tim O’Brien
April-June 2009

When NOAA published its latest climate change research in January, it might have been tempting to file it away as just another dire prediction. The researchers found that, if CO2 emissions continue to rise throughout this century, the consequences will include dramatic increases in sea level, diminished drinking-water supplies, and conditions that rival those of the 1930s Dust Bowl. These days, it’s easy for findings like these to get lost in the seemingly constant stream of grim forecasts, but it would be a mistake to overlook how one of the paper’s key conclusions encapsulates a profound challenge to the environmental community.

The researchers found that, even if global emissions were halted at century’s end, the CO2 concentrations would lock in rising sea levels (among other things) for at least a thousand years. This poses a stark question to conservationists and environmentalists, who have stubbornly argued that reducing emissions is the only appropriate response to climate change—adapting to a changing planet has been seen as tantamount as surrender. But like it or not, the NOAA study underscores that the world is irrevocably changing. The question is, can environmental thinking change along with it?

Although it’s too early to know the answer, some conservationists are starting to accept that it’s time to stop resisting and start adapting. It’s a controversial view, in part because putting adaptation into practice means abandoning long-standing conservation projects in favor of forward-thinking strategies that may or may not work. One of the first places this philosophical shift is playing out is in Florida, where, in an illustration of dilemmas the entire world may soon face, sea-level rise is expected to strike early and often.

Even the most conservative climate models predict sea levels will rise one meter by 2100, which would swamp Florida’s barrier islands and much of its southern tip. A three-meter rise would put much of South Florida, including Miami and Fort Lauderdale, under water. Either scenario means rising waters will force the rapid displacement of people living along Florida’s coast, not to mention many of the state’s endemic species. Similar changes will be seen worldwide; rising waters will likely force millions of people to move inland while inundating millions of hectares of wetlands, islands, and coastal marshes. If current projections are to be believed, this will happen not in some distant future but within a human generation.

That has led Reed Noss, a Central Florida University professor, to position himself at the leading edge of the shift away from traditional conservation. Noss and his colleague, Tom Hoctor, have started sketching out a large-scale plan to preserve much of Florida’s biodiversity, even in the face of massive population shifts. In what he dubs “managed retreat” from the sea, Noss is calling for the surrender of coastal zones to the ocean, for the preservation of areas that would provide habitat to species once they’ve fled inland, and for the development of new property easements based not on where people live today but on where they will live once climate change reworks the landscape.

Such innovative proposals deliver an early glimpse of not only what adaptation strategies might look like but also of the painful tradeoffs that will accompany them. Noss’s ideas, for instance, run headlong into a multibillion-dollar plan to restore the Everglades, even though a huge swath of the swampy land could soon be under water.

On a geologic time scale, sea-level rise is not a new phenomenon, and species have retreated and adapted in the past. The problem this time around, Noss says, is that the rise will happen so fast that plants and animals will not have time to adapt on their own and will have their migrations blocked by roads, buildings, and other human barriers. Further complicating matters, the species that do make it inland will face intense competition for habitat as humans also back away from the coasts. A one-meter sea- level rise would displace almost half of Florida’s population, sending nearly 8 million people dashing to higher ground.

It would also swamp roughly 20 percent of the state’s conservation lands and inundate the habitat at least 26 animal species, placing many of them in danger of extinction. Other species would be forced into a shrinking footprint; the Florida panther, for example, would lose about 23 percent of its habitat. In anticipation of this upheaval, Noss’s plan calls for government and nonprofit agencies to spend the next five to ten years buying upland habitat, where species can find a safe home, and establishing corridors between those reserves and the coasts. He and other researchers have already identified high spots in south Florida and other areas likely to be inundated. Given the state’s low elevation, “there won’t be many of these places,” says Hoctor, of the University of Florida, “but they are the future Florida Keys.”

This is where Noss and Hoctor’s plan rests on another controversial strategy: assisted migration. Unable to move themselves, many species would need to be picked up by people and carried to higher ground. Trapping and moving animals happens all the time; Florida biologists, for example, have been capturing the Key Largo woodrat to breed in captivity. What sets Noss’s plan apart is scale—thousands of animals across a myriad of species would have to be translocated.

Of course, humans will also be on the move, and when push comes to shove, people whose homes are submerged may not have much sympathy for the Atlantic salt marsh snake and other dislodged species. The only way to ensure an orderly retreat, Noss believes, is to plan for this exodus in advance, then slowly execute it over the next 50 to 100 years. That’s where “rolling easements” come in. These would maintain public ownership of the coast and stop property owners from building new seawalls. As the water rolls in and populations move inland, this measure would ensure that a band of coastal ecosystems and habitat remain between human populations and the water’s edge.

Bill Stanley, a climate change expert at The Nature Conservancy, believes radical approaches like Noss’s are exactly what conservationists need to take when the ground could literally be shifting beneath their feet. “If we don’t adapt,” Stanley says, “we’ll be in a heap of trouble.”

There are, to say the least, formidable hurdles to such a plan, the biggest of which may be scientific uncertainty. Despite scientists’ reliance on computer models, it’s simply impossible for those models to factor in enough variables to be completely reliable. For example, a recent paper in Science details how current sea-level projections may be off-base because they don’t factor in the gravitational pull of the ice sheets. In other words, no one knows exactly which lands will be flooded or when those floods will occur. It’s equally difficult to predict how species will fare once they’ve been moved to their new homes; they could get gobbled up by current residents upset at their arrival or run rampant over established species.

And then there’s politics. Many people still don’t accept the reality of global warming, let alone the need for a plan to abandon the coasts and start moving wildlife. Coupled with the uncertainty of predictions, it’s a tall order to expect government to commit the vast funding needed to kick-start comprehensive adaptation planning.

Making matters worse, investing billions of dollars in future-minded adaptation plans means forgoing present-day conservation projects, some of which represent decades of planning. One of the biggest projects is taking place in Noss’s backyard, where a multibillion-dollar restoration of the Everglades is already under way.

There’s a simple sign marking a high point in Everglades National Park. It reads “Rock Reef Pass—3 feet.” It’s not meant to be chilling, but given sea-level projections, it’s a reminder of the bleak future the park could face, says Superintendent Dan Kimball.

Kimball is an apt administrator for the Everglades—his professional life has been all about water. A hydrologist and former head of the National Park Service’s Water Resources Division, he has spent years working to protect water resources. In his current position, he is one of the leading advocates of restoring the park. As such, he stands at the crossroads of what could be one of the early litmus tests of conservationists’ willingness to adapt to a changing planet.

Restoring the 600,000 square-kilometer Everglades National Park has been the dream of biologists, Native Americans, state officials, and conservationists in Florida for decades. Once an incredibly fertile freshwater ecosystem covering roughly 2,850 hectares, it was nourished by a sheet of flowing water emanating from the swamps upstream. Those were drained in the early 1900s, creating Miami, Fort Lauderdale and, for the Everglades, an ecological tragedy. Deprived of their freshwater lifeline, roughly 90 percent of the egrets, ibises, and other wading birds that once populated the area have disappeared while 69 other species, including the Florida panther, are listed as threatened or endangered by the state and federal government.

After years of lobbying and battling, Congress passed the Comprehensive Everglades Restoration Plan, embarking on what amounts to the largest ecological restoration in the history of the world. The heart of the project is to restore the flow of fresh water and rebuild the complex set of ecosystems that include cypress swamps, sawgrass marshes, and mangrove forests. That would return natural habitat for imperiled species, for a hefty price.

The project is expected to cost upwards of $15 billion and take 35 years. It will cover 45,000 square kilometers and create 180 square kilometers of man-made marshes. It will also build a vast freshwater-distribution system: 300 new wells will store the water, which will then be released at a rate of 5.7 billion liters per day to mimic nature’s freshwater flow. The plan, however, has a major wrinkle: much of the 160-kilometer-long, 80-kilometer-wide Everglades is less than three feet above sea level, which means most of the expensive restoration could soon lie beneath the ocean. This has kicked off a debate about whether the Everglades money could be better spent preparing for the future. Instead of spending vast sums on helping species survive within the park’s boundaries, “We need to facilitate species movement out of the Everglades,” Noss says. “It makes no sense to spend billions of dollars . . . when it’s going to be inundated.”

However, in a position that highlights the scientific uncertainties surrounding adaptation, Kimball and others believe restoring the Everglades could actually help thwart sea-level rise, in part because it would strengthen the “freshwater head,” or flow of water that pushes back against the ocean, keeping saltwater from rising into the park. “The best thing we can do to stave off climate change is do everything we can to restore a natural landscape,” says Kimball.

His opinions are backed by the National Research Council. Every two years the Everglades Committee on Independent Scientific Review, an NRC research group, takes a fresh look at the restoration issue. Their conclusion last September was that the uncertainty surrounding sea-level rise actually makes restoration more important.

Virginia Burkett, Chief Scientist for Global Change Research for the USGS agrees. She believes that “eliminating other stressors that would increase resiliency is a win-win situation.” While she doesn’t disagree with Noss, she stresses the situation’s uncertainty, leaving her in the unlikely position of an environmental advocate who thinks current climate projections might be overblown. “We’re not sure we’re going to see three feet of sea-level rise in the next century,” she says. The best thing to do is monitor, she says, and change plans only if sea-level rise accelerates.

The Everglades controversy is a sign of what’s to come as adaptation goes mainstream. In the U.S. and abroad, conservationists are zeroing in on new adaptation strategies that, like those advocated by Noss, depart from traditional approaches for both development and conservation. In the process, they’re delivering an early look at a paradigm that includes a dramatic willingness to re-engineer some ecosystems in order to save others.

From a human development standpoint, the conventional strategy used to combat sea-level rise has been coastal hardening—building sea walls, nourishing or expanding beaches, and creating a solid, static shoreline. In the U.K., officials are abandoning that strategy and methodically preparing to surrender parts of the coastline to the sea. Much of the U.K. coast is lined with grazing marshes created long ago, when estuaries were drained to make more room for agriculture. Those grazing lands will become more and more difficult to protect as sea levels rise, leading planners to divide the entire coast of Britain and Wales into 40 sub-cells. These planners are now deciding which parts of the coast to protect with seawalls and which to surrender, thereby allowing the land to return to salt marsh. The sea has already been allowed to reclaim some small areas, including Cley, a top birding area. “If the land behind the dikes is not valuable, they’ll let [the dikes] fail,” said R.J. Nicholls, professor of coastal engineering at the University of Southampton.

On the conservation front, a more expansive effort is getting under way in North Carolina, where expectations that sea-level rise will gradually obliterate the Outer Banks are leading The Nature Conservancy to consider the sort of intervention that has long been anathema to environmental conversation. Right now, the Outer Banks protect the Albemarle and Pamlico Sounds from intense waves and storm surges, allowing them to flourish as one of the world’s largest and healthiest estuaries. If that shelter disappears, it will jeopardize critical habitats for 300 species of plants and 200 species of animals, including the threatened red wolf. To replace this protective function, Conservancy teams are taking the first steps toward what could become an audacious attempt to re-engineer huge sections of the Carolina coastline.

They are using concrete and oyster shells to construct a network of artificial reefs. The project is small-scale right now, but the Environmental Defense Fund’s Sam Pearsall, who helped plan the reefs when he was director of science at TNC’s North Carolina chapter, says the number of planned reefs needs to be increased as soon as possible. He envisions hundreds of reefs offshore, as well as planting thousands of hectares of bald cypress and establishing salt marshes along the coast “so these areas can make the transition from above-water to below-water.”

It’s all a step, Pearsall hopes, toward helping natural systems adapt to radical change. But the gulf between him and traditional conservationists remains large—many environmentalists are slow to come around, even though time is short. “I brought up the subject at one meeting, and it was like bringing up Satanism,” Pearsall says. “They did not want to talk about it.” ❧

Igual, J.M. et al. 2009. Buying years to extinction: Is compensatory mitigation for marine bycatch a sufficient conservation measure for long-lived seabirds? PLoS ONE DOI: 10.1371/journal.pone.0004826.

It’s payback time—or not. Recent proposals have suggested that long-line fishermen who take in seabirds as bycatch compensate by paying to remove other threats to seabird populations—namely rats, an onshore invasive predator of bird eggs and babies. But controversy remains regarding whether such a scheme could really reverse the trends of seabird populations in decline.

Writing in PLoS ONE, the authors tested whether rat eradication sufficiently boosted the numbers of young Cory’s shearwater, a seabird breeding on islands in the Mediterranean, to make up for adult deaths from fishing line ensnarement. They found that a decrease in rat numbers helped more birds survive to adulthood but that the survival of grownups really mattered most for the health of the overall population. “When adult survival is low, rat eradication would allow us to “buy” years before extinction but does not reverse the process,” says the paper. For long-lived species like the Cory’s shearwater, such “polluter pays” plans can be seen as emergency measures but are not a long-term solution for absolving the biological toll wreaked by the fishermen. ❧

—Jessica Leber

Duncan, R.P. et al. 2009. Do climate envelope models transfer? A manipulative test using dung beetle introductions. Proceedings of the Royal Society B. DOI:10.1098/rspb.2008.1801.

Birds are shifting their ranges north, and butterflies are fleeing toward mountaintops. Predicting exactly where they and other species will live as the earth warms has become something of a cottage industry among biologists. A paper in Proceedings of the Royal Society B, however, points out a potentially fatal flaw of these forecasts: they assume that climate is the only factor limiting a species’ turf.

The researchers use a pokier species—the dung beetle—to prove their point. Thousands of the beetles, which are native to South Africa, were released in Australia in the 1970s and early 1980s. Years later, the authors trekked back to the release sites to check how the beetles were doing. Based on the beetles’ current distributions, the scientists construct and compare “climate envelope models”—the typical way of predicting species’ future ranges—of the dung beetles’ territory in their native and adopted countries. Comparisons for three of the five species tested showed that, in South Africa, other factors (such as natural enemies or food limitations) likely restricted the beetles’ range. Which leads the authors to note that, if modelers want to predict the future, climate should be only one part of the equation. ❧ —Jessica Leber

Horvath, G. et al. 2009. Polarized light pollution: a new kind of ecological photopollution. Frontiers in Ecology and the Environment DOI:10.1890/080129.

Light pollution can happen in the daytime, too—which could be disastrous for some species, according to a study in Frontiers in Ecology and the Environment. At issue are glass buildings, asphalt roads, and even oil slicks that do a surprisingly good job of mirroring the polarized light animals use to recognize bodies of water. Hundreds of species of aquatic insects, not to mention some birds, use the light for navigating to feeding and breeding grounds.

The problem is, dark and shiny man-made surfaces reflect polarized light in much the same way as water, setting what the study’s authors call an “ecological trap.” They witnessed, for example, a dragonfly so mesmerized that it mistakenly laid its eggs on a highway and then died from dehydration and exhaustion. Although the team did not study the overall scope of the problem, they speculate that it could be a widespread and serious hazard. Many aquatic insects experience complete reproductive failure when they lay eggs on artificial polarizers. But the study does offer a glimmer of hope: some simple measures, like painting white hash marks on roads, could disrupt the hypnotic effect. ❧ —Jessica Leber

Kilpatrick, A.M. et al. 2009. Wildlife-livestock conflict: the risk of pathogen transmission from bison to cattle outside Yellowstone National Park. Journal of Applied Ecology. DOI:10.1111/j.1365-2664.2008.01602.x.

So much for “home on the range.” When heavy snow forces Yellowstone bison to move down to nearby ranchlands, wildlife managers try to herd the animals back into the park. If that doesn’t work, the unsuspecting bison are summarily shot.

This aggressive response is part of a decades-old strategy to prevent transmission of the brucellosis virus (Brucella abortus) from bison to cattle. But the force might be disproportionate to the threat: a study in the Journal of Applied Ecology finds it would be almost as effective, and far cheaper, to simply let the bison roam.

The possibility of disease has long worried Montana ranchers, who would lose significant revenue if they lost their “brucellosis-free” status. Hence the “hazing and culling” strategy, which prevents all contact between bison and cattle. But these interventions cost millions of dollars each year and have resulted in the killing of more than 3,400 bison since 2000—even though there has never been a documented case of brucellosis transmission from Yellowstone bison to cattle.

A research team led by A. Marm Kilpatrick set out to quantify how much the current strategy actually reduces the risk of brucellosis transmission. Their model confirmed that preventing contact between bison and cattle is the safest bet. But they found transmission would be unlikely even if managers didn’t intervene.

If hazing and culling were stopped, transmission risk for a population of 5,000 bison (the number living within Yellowstone’s borders) under heavy snowfall conditions would be less than one percent in most years but would rise above 10 percent once every 20 years. So today’s strategy reduces transmission risk from low to slightly lower.

A more cost-effective solution, the researchers suggest, might halt cattle grazing in areas where transmission risk is greatest, compensate ranchers for lost revenue, and let the bison wander where they please. ❧

—Scott Norris

At first glance, the South Orkney Islands could hardly seem less hospitable: they sit just 600 kilometers north of Antarctica, 85 percent of their land mass is covered by glaciers, and temperatures rarely climb above single digits—even in the summer. Despite their desolate appearance, a new study finds the islands are actually a hotspot for marine life, with their waters harboring more species than even the seas surrounding the Galapagos Islands. Led by David Barnes of the British Antarctic Survey, the study published in the Journal of Biogeography represents one of the first attempts to document species totals for any specific Antarctic locale and provides the first estimate of total animal biodiversity for a polar locality. Executing the tally required an extensive search; Barnes’s team sent divers into the icy waters and trawled the ocean floor for organisms living as deep as 1,000 meters. The end result? A total of 1,224 species across all habitats, 1,026 of which were marine organisms. Of those, 821 were crustaceans, mollusks, and other bottom-dwellers.

The research hints at Antarctic organisms’ ability to adapt to climate change. A large percentage of the species sampled are found throughout the Southern Ocean, and many were found at greater depths than previously recorded. This suggests some species can thrive under a range of conditions, meaning they may still be around when—from a human point of view—the South Orkneys are a bit more inviting. ❧

—Scott Norris

Cement’s large carbon footprint stems from its manufacturing process. The raw materials involved (limestone and clay) must be heated to almost 1,500 degrees Celsius, requiring enormous amounts of energy and combustion. Making matters worse, those materials release carbon as they’re heated. In the end, producing just one ton of cement emits a hefty 1.4 tons of carbon.

Thanks to a natural chemical process, cement also absorbs carbon over its lifetime, but it doesn’t soak up enough CO2 to offset the original emissions. Novacem’s engineers set out to rewrite this equation. They designed a new cement that’s based not on limestone but on magnesium silicates. Since these don’t contain carbon, they don’t give off CO2 during manufacture. The cement can also be produced at much lower temperatures, translating into big energy savings.

Even better, Novacem’s concrete absorbs far more carbon than traditional cement does. Each ton of the new product pulls 1.1 tons of CO2 from the atmosphere–which means that over its lifetime, the cement actually soaks up 0.6 tons more carbon than it emits.

—Judy Wexler

This seemingly gruesome behavior is advantageous—it helps keep populations stable. But what gray nurse sharks need now is quantity, not quality. Their population is being decimated by fishing practices that leave them tangled in nets and dangling from hooks meant for other, tastier species. So to boost shark numbers, Australian researcher Nick Otway has cooked up a bizarre remedy: artificial wombs.

Otway, of the New South Wales Department of Primary Industries, has developed a specialized container holding fluids, bacteria, and other elements that mimic the conditions found inside mother sharks. He envisions plucking embryos from pregnant gray nurse sharks, placing them alone into the containers, and eventually releasing them to the wild. ❧
—Justin Matlick

Oczkowski, J.A. et al. 2009. Anthropogenic enhancement of Egypt’s Mediterranean fishery. Proceedings of the National Academy of Sciences DOI:10.1073/pnas.0812568106.

Researchers have uncovered a strange twist in the otherwise sad story of agricultural runoff. Overloaded with nutrients from fertilizer, animal waste, and sewage, parts of the sea have become oxygen-deprived dead zones. But the same force appears to be driving at least one fishery’s dramatic recovery.

That’s the upshot of a study published in PNAS showing that, in the Nile River delta, fish are thriving on runoff from upstream cities and farms. Fish stocks around the Nile’s mouth crashed when the Aswan High Dam was built in the 1960s, cutting off the flow of nutrients downstream. But in the past 20 years, the fishery’s fortunes have more than reversed—today’s catches are nearly three times larger than those before the dam was built.

Autumn Oczkowski, a doctoral candidate at the University of Rhode Island, fingered nitrogen-rich fertilizer as the main, if unlikely, savior. Oczkowski and her colleagues analyzed nitrogen isotopes in more than 600 fish they bought throughout the delta region and along Egypt’s Mediterranean coast. The team found that about 80 percent of the fish offshore of the delta rely on nutrients from human sources. And neither pesticides nor heavy metals appear to be tainting the fish.

The Nile delta’s contradictory situation stems, in part, from the Mediterranean’s low nutrient levels; adding fertilizer gives the food chain a boost. It’s possible that, if runoff increases, nutrient overload might hinder the area’s ability to support fish. But stopping runoff would likely make the fishery go belly-up once more. ❧

—Rebecca Kessler

Each spring and fall, a grisly spectacle plays out above the North Sea. As millions of migrating birds fly overhead, the lights of offshore oil and gas installations throw the birds off course. Some birds die in collisions with the installations, while others spend hours circling until exhaustion forces them to fall from the sky. Hundreds of disoriented birds congregate on the installations’ decks, and some stay long enough to die of starvation. Now, a group of European researchers has come up with a surprisingly simple solution: green light bulbs.

Two Dutch companies, Royal Philips Electronics and Nederlandse Aardolie Maatschappij BV, an oil and gas company, set out to develop lights that wouldn’t interfere with the birds but would still provide adequate illumination for oil and gas workers to do their jobs safely. Field tests confirmed earlier findings that blue or green light is much less disorienting to birds than red or white—possibly because the shorter wavelengths are less disruptive to a bird’s magnetic compass.

Blue light was the least distracting to birds, but it was uncomfortable for workers. Green light is almost as innocuous as blue and actually enhances people’s depth perception. So a compromise was struck, and the researchers developed new lights around a spectrum that includes lots of green and just a little red, which ensures workers can see emergency equipment if they need it.

The lights are now being tested on a North Sea gas platform. So far, workers seem to be happy, and the number of migratory birds lingering near the rig has been cut to somewhere between one-half and one-tenth the original number. Whether the new lights are equally copacetic for other nearby organisms remains to be seen.

The lights could eventually be installed on all North Sea rigs; researchers believe such a move would reduce the number of impacted birds from roughly 6 million to about 600,000. And there are plenty of other good places to put them. Airports, highways, and a host of other lighted structures wreak havoc on bird populations. The new bulbs present a solution that’s far more likely to succeed than asking the world to flip the “off” switch. ❧ —Rebecca Kessler

Ridgwell, A. et al. 2009. Tackling regional climate change by leaf albedo bio-geoengineering. Current Biology. DOI:10.1016/j.cub.2008.12.025.

Farm fields with bling may be the next big thing in agriculture, if scientists from the University of Bristol have their say. In Current Biology, they propose that farmers fight climate change by planting crops that reflect more sunlight back to space. Some varieties of corn, wheat, and barley have leaves that are especially reflective. So why not breed crops to maximize this effect? The researchers note that farmers already pick seed strains to yield juicier tomatoes and wheat that’s especially good for making bread; all they’d need to do is add another criterion to their list. By inserting the crop change into a global climate model, the authors found that glimmering fields could cool summertime temperatures in much of Europe, North America, and Asia by up to one degree Celsius—potentially enough to relieve the most extreme droughts and heat waves. The reduction is equivalent to offsetting one-fifth of the seasonal regional warming expected by the end of the century. In other words, this “bio-geoengineering” approach might be a relatively cheap and simple way to beat the heat. ❧ —Jessica Leber

Hanson, T. et al. 2009. Warfare in biodiversity hotspots. Conservation Biology DOI: 10.1111/j.1523-1739.2009.01166.x

Not even conservation areas are safe from war. Eighty percent of the 146 armed conflicts occurring between 1950 and 2000 took place within the world’s biodiversity hotspots, according to a study in Conservation Biology.

To reach this conclusion, researchers cross-referenced the locations of conflicts incurring more than 1,000 casualties with Conservation International’s list of 34 biodiversity hotspots. Only 11 of these regions escaped warfare over the five-decade period. This trend is worrisome, the researchers say, because war’s environmental costs can be nearly as high as its human toll. During war, conservation activities are usually suspended and protected areas often abandoned by staff. What’s more, refugees often turn to poaching, which can decimate wildlife populations, and timber harvests have been used to fund military operations. To avert these dangers, the authors call on the conservation community to maintain direct involvement in war zones and to recommend that biodiversity protection become a goal of war-related humanitarian and reconstruction programs. ❧

—Jessica Leber

Johnston, M. et al. 2008. Resetting global expectations from agricultural biofuels. Environmental Research Letters DOI:10.1088/1748-9326/4/1/014004

From corn and castor to sorghum and sweet potato, it seems like almost any crop is capable of running our cars these days. But as biofuel boosters talk up production potential of these various feedstocks, new data suggest that most claims of how much fuel can be farmed from the land are wildly exaggerated.

The study, published in Environmental Research Letters, used the most- detailed global agricultural production maps in the world to calculate the actual yields—the amount of fuel produced per hectare of farmed land—of 20 different biofuel crops in 238 countries.

For many crops, the authors found that previous reports had overestimated the potential global yield by 100 percent or more. Wheat, for example, should make close to 3,000 liters of ethanol per hectare of land, according to often-cited numbers. The new analysis puts the median at less than half that amount. The overall disparity is because researchers had been taking United States or European production values and extrapolating them worldwide, according to Matt Johnston, a researcher at University of Wisconsin-Madison and the paper’s lead author.

In the real world, however, climate, soil, fertilizer inputs, management practices, and even social and economic issues all affect the quantities farmers reap. And while the study shows that previous numbers were optimistic even for developed countries, biofuel crops will be increasingly farmed in developing nations, where yields are consistently far lower. ❧

—Jessica Leber