The Importance of Wetland and Upland Grassland Complexes for Waterfowl Production

Breeding Habitat, Not Harvest, Drives Waterfowl Populations

The success of waterfowl populations is fundamentally rooted in the quality of their breeding habitat, not in harvest regulations. Scientific studies have consistently shown that in most years and for most species, regulated harvest has a negligible impact on long-term waterfowl population dynamics.

This is because harvest mortality is generally compensatory rather than additive (Anderson & Burnham, 1976). In contrast, the availability and quality of breeding habitats directly influence nest success, brood survival, and overall recruitment rates, which ultimately determine fall population sizes (Hoekman et al., 2002). Thus, conservation efforts focused on maintaining or improving breeding habitat are far more effective at influencing population trends than further restrictions on harvest.

The Prairie Pothole Region: North America’s Duck Factory

The Prairie Pothole Region (PPR) spans portions of the northern United States and southern Canadian prairies and is widely recognized as the most critical waterfowl breeding area on the continent. It contains a unique mosaic of temporary and seasonal wetlands interspersed within upland grasslands, which together provide optimal nesting and brood-rearing habitat.

Although the PPR comprises only a small fraction of North America's land area, it produces more than 50 percent of the continent’s duck population during wet years (Doherty et al., 2013). Species such as mallards (Anas platyrhynchos), northern pintails (Anas acuta), gadwalls (Mareca strepera), and blue-winged teal (Spatula discors) rely heavily on these grassland–wetland complexes to complete their life cycles.

The Impact of 2025 Drought Conditions on the Breeding Grounds

Preliminary insights from the 2025 Breeding Population and Habitat Survey (BPOP), though not yet formally published, suggest that conditions in the U.S. PPR were severely dry during the critical May breeding window. Reports based on early field data and agency social media releases indicate a roughly 38 percent decline in pond counts compared to 2024. In North Dakota, the heart of the PPR, many temporary wetlands were either dry or significantly reduced in size.

This has likely contributed to an approximate 26 percent decline in the mallard breeding population, among other species. Early-nesting species such as mallards and pintails may have overflown traditional breeding areas in search of wetter habitat farther north. However, these shifts can disrupt nesting success and reduce overall recruitment due to suboptimal habitat or increased energy expenditure during prolonged migration.

Drought Cascades: Skipped Nesting and Decreased Production

When breeding wetlands are dry, ducks either forego nesting altogether or experience lower nest success due to increased predation risk and lack of quality brood-rearing cover. Even in species that are capable of renesting, such as mallards, drought reduces clutch sizes and impairs overall reproductive success.

The net result is reduced juvenile recruitment into the fall population, which negatively affects not only recreational hunting opportunities but also the broader ecological services waterfowl provide across wetland systems (Hoekman et al., 2002). As climate variability increases and droughts become more frequent in the PPR, the resiliency of waterfowl populations will increasingly depend on the stability and extent of high-quality breeding habitat.

Habitat Loss: An Ongoing Threat to Production

Even during years with favorable moisture conditions, the capacity of the PPR to support breeding waterfowl has been significantly diminished by land-use changes. Native grasslands have been steadily converted to cropland, and countless wetland basins have been drained to improve agricultural efficiency. Since 2001, the U.S. has lost an estimated 670,000 acres of vegetated wetlands annually, with much of this occurring in key waterfowl production zones (Dahl & Darrah, 2022).

Similarly, the Conservation Reserve Program (CRP), which once provided extensive nesting habitat, has seen enrollment decline by more than 50 percent in core breeding regions since 2007. This loss of habitat not only decreases the number of birds produced each year, but also reduces the landscape’s ability to buffer against climatic variability.

The Role of Private Landowners in Conservation

Because a significant portion of remaining wetland and grassland habitat exists on private lands, landowners have a critical role to play in waterfowl conservation. Landowners can implement conservation practices such as preserving seasonal wetlands, planting native grasses, and maintaining vegetative buffers to enhance nesting and brood-rearing habitat.

Programs like CRP and the Wetlands Reserve Easement (WRE) program, funded through the Farm Bill, offer cost-share and rental payments for such conservation measures. While enrollment in these programs has declined due to economic pressures and fluctuating policy support, studies show that landowners remain largely supportive of voluntary conservation programs when incentives are adequate (Claassen et al., 2017). Expanding and reinvigorating these programs is essential to securing the future of waterfowl production.

2025 Outlook: A Critical Inflection Point

Although late-spring rainfall in 2025 offered some habitat recovery in parts of the PPR, these improvements came too late to benefit early-nesting ducks. The breeding success of later-nesting species may improve slightly, but the broader implications of early-season drought remain. The 2025 breeding season exemplifies how even a single dry spring, when compounded by long-term habitat loss, can severely limit duck production. Without intervention, these patterns may become the norm rather than the exception. The lesson from 2025 is clear: conservation must focus on breeding habitat resilience, preserving wetlands and grasslands, if we hope to sustain waterfowl populations for future generations.

References

Anderson, D. R., & Burnham, K. P. (1976). Population ecology of the mallard: VI. The effect of exploitation on survival. U.S. Fish and Wildlife Service Resource Publication, 128.

Claassen, R., Duquette, E., & Johansson, R. (2017). Cost-effective targeting of conservation investments to reduce nutrient flows. American Journal of Agricultural Economics, 99(1), 102–123. https://doi.org/10.1093/ajae/aaw074

Dahl, T. E., & Darrah, A. (2022). Status and trends of wetlands in the conterminous United States, 2001 to 2016. U.S. Fish and Wildlife Service.

Doherty, K. E., Ryba, A. J., Stemler, C. L., Niemuth, N. D., & Meeks, W. A. (2013). Conservation planning in an era of change: State of the U.S. Prairie Pothole Region. Wildlife Society Bulletin, 37(3), 546–563. https://doi.org/10.1002/wsb.294

Hoekman, S. T., Mills, L. S., Howerter, D. W., Devries, J. H., & Ball, I. J. (2002). Sensitivity analyses of the life cycle of midcontinent mallards. Journal of Wildlife Management, 66(3), 883–900. https://doi.org/10.2307/3802933