Biofuels and Ducks

How will ethanol fuel affect breeding waterfowl?

By Jim Ringelman, Ph.D.

As a rule, change comes slowly to the agricultural landscape of the Prairie Pothole Region. Change can be risky, and farmers are risk-averse by nature. Modern agribusiness is characterized by huge capital investments, large volumes of money moving into and then back out of checkbooks, and—in the end—thin profit margins. There is little room for experimentation and a failed crop year. But a daring new attitude is sweeping across farm country, and it’s setting the stage for dramatic changes in land use. It’s “ethanol fever.”

Companies have been fermenting corn into ethanol for decades, and many of us have filled our vehicles with a 10 percent blend of their product. But until recently, few of us have given serious thought to the need to wean our nation off foreign oil. And hardly anyone knew there was a plant called switchgrass that, given time and new technology, might be an important ingredient in the recipe for energy independence.

How quickly things change. Reducing our dependence on foreign oil is now a cornerstone of federal policy. And that obscure plant called switchgrass emerged in the public consciousness when President Bush referenced it in his 2006 State of the Union address. From all indications, “biofuels” are here to stay.

Energy from Biomass

Biofuels are energy sources derived from plants or other living organisms (biomass). Converting plant matter to biofuel can be as simple as picking the stems and leaves from a field, bundling them up, and then transporting them to a power plant where they are burned—together with coal and other fuels—to generate electricity. But most often, the term biofuel refers to a liquid derived from plant material and used as a transportation fuel. Ethanol and biodiesel are the most common examples.


Energy technology is evolving quickly, and the list of biofuels and useful coproducts continues to grow. Today, one biofuel—ethanol—is the focus of attention. Fermenting ethanol from corn or other grains is a proven technology, and engines have already been adapted to burn gasoline-ethanol blends. Currently, there are 116 corn ethanol plants in the United States, and 79 more are being built or are planned. At a conversion rate of 2.8 gallons of ethanol per bushel of corn, producing the 5.5 billion gallons of ethanol flowing from today’s plants requires a veritable mountain of the golden grain—nearly 2 billion bushels. And if all the new plants are built, corn ethanol production will double. All of this is moving us toward “30 by 30,” the goal of replacing 30 percent of our nation’s transportation fuel consumption with renewable energy by the year 2030.

But consider that these old and new plants, together with plant expansions, will have a combined need for 4.5 billion bushels of corn. That staggering number represents 42 percent of the 2006 U.S. corn harvest. This new demand will cut into the corn supply that is already being used for animal feed and as a key ingredient (in various forms) in thousands of food products, most notably processed food. Several months ago, when the numbers were added up, speculation arose that someday soon there may not be enough corn to go around. That speculation evaporated during the last State of the Union address, when the president raised the ethanol bar by setting a national goal of producing 35 billion gallons by 2017, an amount more than six times current production. Now there is little doubt that corn supplies will be stretched thin, and a new dimension has been added to the ethanol challenge.

Our nation’s ethanol production goals cannot be achieved solely with corn and other starch grains. It will require the use of new sources of biomass, such as switchgrass, wheat straw, and corn stover (cornstalks and leaves). In each case, the portion of the plant digested to make ethanol is the cellulose—the material that helps give plants their structural support. The ethanol that results from the digestion process is called “cellulosic ethanol.” It is created using specialized enzymes and a series of complex processes.

In the near future, corn and cellulosic ethanol feedstocks may well be competing for the same acres of farmland. This includes land that is now growing wheat, beef, or—in the case of land enrolled in the Conservation Reserve Program (CRP)—ducklings. In the Prairie Pothole Region (PPR), the heart of North America’s duck factory, big changes are coming. What will be the net effect on duck populations? As the saying goes, there’s good news, and there’s bad news.

First, the Bad News

Most experts believe that commercial-scale, cellulosic ethanol processing plants will not come on line for five years or more. Until then, the demand for corn ethanol is expected to increase dramatically. Regrettably, when it comes to breeding ducks, it is hard to find a silver lining in a forecast for more corn acres. In fact, the demand for more corn is likely to throw a big wrench into the gears of the duck factory.

Typical of any supply-and-demand relationship, when the demand for corn is high, so is its price. If corn growers receive a high price for their product, they can then afford to invest more in land and land rental. Farmers who grow less profitable crops get squeezed out. Simple supply-and-demand economics force those currently receiving a low return on their land investment to reconsider how their land can best be used to generate revenue.

An obvious concern associated with increased corn production is the fate of land enrolled in CRP, a program that was created in the 1985 Farm Bill to idle highly erodible land by restoring it to grassland. As the many other conservation benefits of CRP emerged—including the addition of 2.1 million ducks each year to the fall flight—the program became recognized as the most significant and successful conservation initiative ever implemented by the U.S. Department of Agriculture (USDA). Now, those in search of more corn ground are viewing CRP land as up for grabs. The USDA evidently agrees. Last February, it announced that no new CRP signups would be held in 2007 and 2008, and that it is considering allowing landowners currently enrolled in CRP to terminate their contracts early—all for the stated purpose of providing more acreage to meet the demand for corn. But cornfields do not provide suitable nesting habitat for ducks. And depending on how many acres of CRP are lost in the PPR, some portion of those 2.1 million ducks will not be flying south each autumn.

The demand for corn will also put pressure on the 22.3 million acres of remaining native prairie grassland in the U.S. Prairie Pothole Region. Newly broken prairie will not grow much corn. In general, the soils are too poor, and the climate is often unsuitable for corn. But some newly broken prairie may be suitable for wheat and other crops that will be displaced by corn on existing cropland. And even if the native grasslands remain intact, the demand for corn and cropland in general is driving up the cost of all land dramatically. These increased land values also affect the region’s other producers—cattle ranchers.

Even though cattle prices have been good for the last few years, the economics of ranching hinge on being able to buy or rent pasture at an affordable price. Higher land prices and rental rates squeeze the rancher’s bottom line. Further compounding the problem are the high costs ranchers incur when they take their livestock to the feeder—the last step in the cattle-rearing process when the animals are fattened on that increasingly valuable commodity: corn. Cattle feeders simply pass on their higher corn prices to ranchers. If a perfect storm of high pasture values, high feeder costs, and a collapse in cattle prices occurs, many ranchers in the Prairie Pothole Region may be driven out of business.

The livestock industry is native prairie’s “reason for being,” at least in an economic sense. If that industry were to disappear today, no obvious economic return could then be realized from native prairie grasslands. Yet history tells us that some creative mind will find a way to make money from the land. If this new industry does not involve keeping the grass “right side up,” what then for the waterfowl that have been nesting on this prairie for the last 10,000 years?

The expansion of corn for ethanol may also have unintended and unforeseen consequences for that other critical element in the duck production equation—wetlands. Currently, millions of wetlands in the Prairie Pothole Region are protected by a strong disincentive within the federal Farm Bill. Very simply, if farmers choose to drain a wetland, they disqualify themselves from all Farm Bill programs, including commodity payments that compensate them for low yields and low crop prices. To date, this disincentive has been very effective at protecting wetlands from drainage. But its effectiveness hinges on low or volatile commodity prices and the need for farmers to manage their risk in the face of these circumstances. If prices for corn increase and remain stable, as they might under a long-term contract to supply an ethanol plant, some farmers may not need or expect to receive commodity payments. That scenario effectively removes the protection afforded wetlands, and widespread wetland drainage could be the result.

The (Hopefully) Good News

If ducks can weather the corn ethanol storm, good news may be on the horizon. The cellulosic ethanol industry, if implemented in a duck-friendly way, could be an asset to waterfowl production. The key lies in the nature of the feedstock, what land uses it displaces, and how it is harvested. In this context, all duck enthusiasts should be pulling for a perennial grass crop like switchgrass, as it clearly holds the most promise for waterfowl benefits.

Switchgrass, like other perennial plants being considered as biofuels, is a tall, dense grass that makes the most of the sun’s energy and the soil’s nutrients. The economics of cellulosic ethanol are all about the tons of biomass that can be grown on an acre of ground. Currently, switchgrass varieties being grown in the Prairie Pothole Region annually yield from 2 to 3 tons per acre. But new varieties being developed through advanced genetics technology may eventually yield as much as 10 tons per acre annually. Most importantly, grasses used to produce cellulosic ethanol are harvested after the growing season, in fall or winter. So the switchgrass stubble that emerges from snow banks to greet mallards in the spring will not be disturbed during the nesting season. The key is to cut the switchgrass high enough (ideally 12 inches or more) so that ducks perceive the stubble as attractive nesting cover.

Besides stubble height, there is another important variable in assessing the net effect of a perennial biomass crop on duck production. That variable is the previous use of the land now dedicated to growing a biofuel crop. If switchgrass is planted on cropland that used to be cultivated every year, the net effect on ducks will almost always be positive. Annually tilled crops (except for winter wheat) provide poor nesting habitat for ducks. But if switchgrass replaces CRP or native prairie, duck production will be negatively affected. Grassland left completely undisturbed (in the case of CRP) or grazed (in the case of native prairie) is generally more productive for ducks than grassland that is harvested every year, even if harvest occurs during the fall.

One important economic consideration for cellulosic feedstocks like switchgrass is the transportation distance from field to processing plant. At current switchgrass yields, the maximum transport distance is about a 50-mile radius. So policies intended to encourage the cellulosic ethanol industry should recognize the need to cluster dedicated biomass crops near proposed or existing plants, rather than, for example, allowing all 7.8 million acres of CRP in the Prairie Pothole Region to be opened up as a potential feedstock. To do so would ensure that more than 90 percent of the biomass would be too far from a processing plant to be used for fuel production.

The Challenges Ahead

It is possible for ducks and biofuels to coexist. In the near term, if corn ground is expanded into existing cropland and the crops displaced do not expand into native prairie or land now enrolled in CRP, detrimental effects on waterfowl will be minimized. If switchgrass and other perennial grasses are planted on current cropland and managed for benefits that include both energy and wildlife, then society and ducks will both win.

Clearly, few emerging industries have as much potential to shape the landscape, and the habitat on which ducks depend, as biofuels. Ducks Unlimited is committed to helping shape the renewable energy industry in a productive way. If waterfowlers, conservationists, and industry leaders can forge an alliance and agree upfront to create a truly “green” industry that serves our collective interests, there is reason for optimism in duck country.

Corn Marches Northwest

Corn is among the most highly modified and improved crops in the history of agriculture. For decades, traditional crossbreeding techniques have resulted in remarkable increases in corn yield. Now, a new wave of advanced genetics opens the door for advancements as great as, and possibly greater than, those that occurred in the past.

With “marker-assisted” breeding, genetic markers are used to identify the desired characteristics in a plant while it is a seedling. This allows rapid development of new corn varieties because breeders need not wait for plants to mature and flower, as they would with traditional crossbreeding techniques. In addition, “transgenic” technology allows breeders to insert genes from different organisms into the corn plant. For example, if one discovers arctic plants with genes that allow them to survive subfreezing temperatures, geneticists may be able to isolate the genes responsible for these traits and insert them into the corn genome.

What does all this have to do with ducks? Breeders are currently focused on developing corn that is drought- and cold-tolerant and matures earlier than current varieties. Greater tolerance to drought would expand the geographic range of corn westward, and increased cold tolerance and earlier maturation moves the range north. Almost inevitably, this expansion is likely to occur at the expense of existing grasslands and wetlands. The intensive agricultural techniques required for corn production have already transformed the Prairie Pothole Region of Iowa and Minnesota from a rich waterfowl production area to cornfields stretching to the horizon. The bottom line is that when the core of the duck factory becomes a corn factory, nesting habitat and wetlands disappear, and ducks lose.

Switchgrass for ethanol and ducks?

Switchgrass has been used for decades to create habitat for nesting ducks. However, it is typically used as one of several species in a mix of grasses, and after establishment, these plantings are usually not harvested for hay. Currently, the enzyme systems used to digest cellulose can process only a single plant species at a time, so stands composed entirely of switchgrass are expected to be planted. Will ducks nest in pure stands of switchgrass, and will the switchgrass stubble that remains from the fall harvest be attractive to them as nesting cover?

To resolve these questions, Ducks Unlimited biologists are planning a collaborative study with Ceres Inc., the leading developer of biomass crops. Under contract with DU, farmers will plant switchgrass fields and manage them as they would for biomass production. At harvest time, farmers will cut the grass at two heights—6 inches and 12 inches—and researchers will then track duck nesting density and success. Scientists will also evaluate the effect on other birds as well as on “eco-assets” like the amount of organic carbon stored in the soil. Such assets are becoming marketable as a way to combat global warming and would provide additional income to the farmer.

If Congress provides funds for this study, DU and Ceres will be positioned to recommend management practices that not only enhance the production of switchgrass for ethanol but also benefit ducks, other birds, and the environment.

Dr. Jim Ringelman is director of conservation programs at DU's Great Plains Office.