By Mike Anderson, Ph.D.
No matter what you’ve thought about climate change, much has changed in the past two years. Conversations among waterfowl managers, scientists, and many sportsmen and -women have shifted from “Is it happening?” to “How can we adapt to the changes unfolding?”
In 2007 the Inter-Governmental Panel on Climate Change (IPCC) issued four authoritative reports about how Earth’s climate has changed. They also offered a range of predictions about the future and advice about responding. In a global nutshell, patterns of temperature and precipitation have changed significantly over the last 150 years, but in ways that differ among geographic regions. Change is likely to continue for many decades or longer. We can expect a future that on average will be warmer and, depending on locale, wetter or drier than in the recent past.
The effects of these changes on North American waterfowl habitats, Ducks Unlimited’s conservation work, and the fortunes of waterfowl hunters could be profound. Consequently, DU is taking steps to keep informed and, wherever possible, incorporate climate science into its conservation planning.
How Could Climate Change Affect Ducks?
While climate change may affect waterfowl directly (e.g., by altering timing of migration), more serious impacts could occur through effects on habitat. Projections for the next 100 years indicate warming in most areas, changing patterns of precipitation, accelerating sea-level rise, declining snowpacks, and increasing frequency and intensity of severe weather. Consequences for waterfowl habitat could include changes in the timing and duration of when wetlands are wet, changes in land use, northward expansion of invasive species, and greater challenges for water management.
DU’s International Conservation Plan has identified North America’s two most important waterfowl breeding areas—the Prairie Pothole Region and the western boreal forest—as our top priority conservation regions. Next in importance are the continent’s key waterfowl wintering areas: the Central Valley of California, Gulf Coast, and Mississippi Alluvial Valley. Waterfowl could face significant climate-related impacts in these high-priority areas.
In the Prairie Pothole Region, for example, average temperatures have increased over the past century, and all global climate models predict further warming and a reduction in average soil moisture in this region. Expected ecological changes include fewer wetlands on average, shorter duration of flooding in wetlands, and greater annual variability in surface water—in short, both deluge and drought.
Rapid alternation between wet and dry years might actually be helpful to ducks, whose mobility allows them to respond more rapidly to changing conditions than can their predators. Prolonged drought would be another matter. Thus, future patterns of year-to-year variability in precipitation will be important to waterfowl.