By Johann Walker, Ph.D., and Scott Stephens, Ph.D.
By most measures, these are good times for ducks. Last spring, a record 49.2 million breeding ducks were surveyed across major waterfowl breeding areas in the United States and Canada. In addition, four of the five largest breeding duck populations recorded since surveys began in 1955 have occurred during the past five years.
Duck numbers have soared largely in response to several consecutive years of unusually wet weather in the Prairie Pothole Region (PPR), commonly known as the Duck Factory because of its importance to breeding waterfowl. In recent years the Duck Factory has lived up to its name. Although the PPR encompasses only about one-third of the traditional survey area, the region has recently supported 60 to 70 percent of all surveyed breeding ducks.
During wet springs, millions of "pothole" wetlands dot the prairie landscape, attracting large numbers of breeding waterfowl. These small, seasonally flooded ponds teem with protein-rich invertebrates, which nesting hens consume to fuel egg production. Large numbers of these wetlands allow breeding pairs to disperse widely, minimizing disturbance and competition from other pairs of the same species. Native prairie and other grasslands, fall-seeded cereal crops, and wooded parkland habitats provide secure places for mallards, northern pintails, blue-winged teal, and other ducks to nest and hatch their broods.
The most important lesson from recent years of record-high duck populations is that adequate wetland and upland habitat still exists in the PPR to produce impressive fall flights of waterfowl when wet weather conditions prevail. The ongoing challenge for Ducks Unlimited and our conservation partners is to maintain those habitats as pressure mounts to convert them to other uses. Agricultural intensification is the primary driver of habitat loss on the prairies, and the vast majority of the wetlands and grasslands in this region are unprotected from conversion to cropland. Ninety percent of the land in the PPR is privately owned and used for agricultural production. In order to conserve the region's wetland and grassland habitat base, we must continue to develop and deliver conservation programs that are attractive to agricultural producers, to promote public policies that help fund conservation programs and reduce habitat loss, and to back our efforts with solid science. Let's take a closer look at how past and present interactions between agriculture and habitat impact prairie-breeding waterfowl and how this knowledge is helping us work with farmers and ranchers to ensure a bright future for North America's duck populations.
Historic Habitat Loss
One hundred and fifty years ago, the PPR was largely an unbroken expanse of native grassland and parkland interspersed with millions of shallow wetlands formed by past glacial activity. Periods of drought and deluge, huge roaming herds of bison, and frequent wildfires were the main forces of change on the landscape. The collective influence of these landscape-level forces created areas of incredibly productive wetland and grassland habitat, and this dynamic ecosystem had the capacity to support immense populations of breeding ducks. During periods of wet weather, the PPR likely supported breeding duck numbers several times greater than even the largest populations we have witnessed in recent years.
Everything changed when European immigrants began to arrive on the prairies during the late 1800s. These enterprising settlers soon discovered that the fertile prairie soils made excellent farmland, and they went to work breaking the native sod and draining potholes to produce food and fiber for a growing world population. Sodbusting peaked during the homestead era and slowed somewhat during the latter half of the 20th century, by which time the most productive soils had been brought under the plow. Widespread drainage of potholes reached its height in the early to mid-1900s and decreased somewhat during the 1970s and 1980s in the United States when wetland protections were enacted.
Current Threats to Prairie Wetlands and Grasslands
Today the PPR is largely an agricultural landscape. More than half the region's original potholes have been drained, and most of its native grassland has been broken. In many areas, more than 90 percent of both wetlands and grasslands have been lost. Overall, approximately 70 percent of the PPR now consists of cultivated cropland, and the remaining grassland is managed primarily as pasture or forage for cattle. While prairie wetlands and grasslands continue to support impressive numbers of breeding ducks, changing agricultural practices combined with rising world demand for food, fuel, and fiber threaten the future of these crucial habitats and the health of waterfowl populations.
In the U.S. portion of the PPR, rising commodity prices and soaring land values have fueled the conversion of millions of acres of native prairie and restored grassland formerly enrolled in the Conservation Reserve Program. Researchers with South Dakota State University estimate that nearly 500,000 acres of grassland were converted to corn and soybeans in North and South Dakota from 2006 to 2011. On a positive note, a Sodsaver provision in the new Farm Bill has reduced the economic incentive for farmers to break native grassland by decreasing the subsidy paid for crop insurance, which will hopefully slow the rate of grassland loss in the short term.
Across Prairie Canada, the abundance of grassland on the landscape is largely determined by the relative profitability of growing grain versus raising cattle. Since 2001, grassland acres have actually increased on the Canadian prairies as a result of strong cattle prices. However, more recent trends have favored grain production, and grassland is once again being converted to cropland in Prairie Canada.
The greatest threat currently facing waterfowl populations, however, remains the loss and degradation of small prairie wetlands. Wetland drainage in the U.S. portion of the PPR has been slowed somewhat by the Swampbuster provision in the Farm Bill, which disallows wetland drainage in return for subsidized crop insurance. Nevertheless, the conversion of prairie potholes, especially the shallow temporary and ephemeral wetlands that are so important to breeding ducks, continues at an alarming rate. Of particular concern is the rapid advance of subsurface "tile" drainage that is following the expansion of corn and soybeans in the Dakotas. Subsurface drainage has the potential to starve wetlands of much-needed runoff as snow melts in spring, creating the equivalent of permanent drought conditions for breeding ducks. Wetland drainage also continues to be an ongoing challenge across Prairie Canada as commodity prices drive demand for new arable acres. Significant wetland drainage has been occurring on the Canadian prairies during the past decade, with especially high rates of habitat loss in east-central Saskatchewan.
Wetland drainage reduces both the number of breeding pairs that the landscape can support and their reproductive success, and the conversion of upland cover reduces nesting success. Together, loss of wetlands and nesting cover is a one-two punch that ultimately will decrease the abundance and productivity of ducks. If DU and our conservation partners hope to continue to fill the skies with ducks in the future, we must find new ways to stop the loss of wetlands and nesting cover across the PPR.
The Way Forward
Expanding our efforts to directly protect and restore wetlands and surrounding upland habitats is a top priority for DU and our conservation partners in the PPR. Revolving land acquisitions and purchased conservation easements allow DU to protect high-quality existing habitat that is at risk of being lost and to restore and protect wetland and grassland habitats on less productive agricultural lands. Great opportunities exist to purchase easements and acquire land for waterfowl habitat conservation across the PPR. In North and South Dakota, more than 1,200 landowners are currently on a waiting list for conservation easements that would protect over 250,000 acres of highly productive waterfowl breeding habitat.
Much-needed additional funding for conservation easements will be provided by the Federal Duck Stamp Act of 2014, which raises the price of the stamp from $15 to $25 beginning this year and commits the $10 increase to purchasing conservation easements on private lands. Extension and stewardship programs, in which DU works with farmers and ranchers to restore and enhance wetland and upland habitats, help build relationships with landowners that often lead to longer-term protection agreements. In addition, DU's winter wheat program offers farmers a profitable, waterfowl-friendly alternative to spring-seeded crops, while also providing secure nesting cover for ducks on cropland- dominated landscapes.
Another key component of DU's overall conservation strategy is to promote public policies that protect wetlands. Studies suggest that the Swampbuster provision in the current Farm Bill will likely prevent the drainage of at least 2,000 acres of wetlands per year in the U.S. PPR. In Canada, where jurisdiction over wetlands lies at the provincial level, DU Canada (DUC) has been working diligently with the governments of Alberta, Saskatchewan, and Manitoba to improve wetland protection policies in those provinces. DUC's efforts are gaining traction as a result of substantial flooding that occurred in 2011 and 2014 across Saskatchewan and Manitoba. DUC research showing the cause-and-effect relationship between wetland drainage and flooding has underscored the need for stronger wetland protection policies in Prairie Canada. If successfully implemented, these policies will help protect millions of acres of prairie wetlands vitally important to duck populations.
DU's habitat conservation programs and public policy work have always been grounded in sound science, and investing in research remains a high priority to ensure that our conservation efforts are both efficient and effective. We recognize that to be successful in an ever-changing world, we must broaden and deepen our knowledge. Accordingly, we have expanded our areas of study beyond the breeding ecology and life history of ducks to ecological goods and services provided by wetlands and to the attitudes and values of agricultural producers.
The essential question for DU and our partners is how do we keep the table set for breeding ducks so their populations can grow rapidly when wetland conditions are favorable in the PPR. To meet this objective, we are employing a flexible, science-based strategy that includes a variety of long- and short-term conservation programs that are economically attractive to agricultural producers. We are also making the case, both to policymakers and the public, for additional conservation funding as well as stronger protections for wetlands and grasslands based on sound science and economics. Collectively, these efforts are the foundation of DU's Preserve Our Prairies Initiative, an international effort to conserve North America's most important waterfowl breeding habitats in both the U.S. and Canadian portions of the PPR. For more information on how you can support this vital conservation effort and help ensure a bright future for waterfowl and our waterfowling traditions, visit the DU website at ducks.org/preserveourprairies.
Dr. Johann Walker is DU's director of conservation programs in North Dakota, South Dakota, and Montana. Based in Stonewall, Manitoba, Dr. Scott Stephens is director of regional operations in DU Canada's Prairie Region.