How do wildfires affect waterfowl?

Fire and waterfowl

Fire has been a natural part of many Canadian landscapes for thousands of years. Waterfowl have long nested, migrated and raised young in habitats shaped by periodic wildfire. In many ecosystems, fire helps recycle nutrients, renew plant communities and create a diversity of habitat conditions.

What worries conservationists is that fire seasons are starting earlier, ending later, and, in some regions, producing larger and more severe wildfires than in the past. In some cases, these fires are burning deeper into soil and affecting ecosystems in ways that were historically uncommon. Longer fire seasons, more frequent droughts and more severe wildfires may leave less time for habitats to recover between disturbances.

What happens to ducks during a wildfire?

Despite the dramatic nature of wildfire, research in Canada’s boreal forest suggests waterfowl populations have historically been resilient to fire, with no detectable effects on overall population size or long-term trends. Individual birds, however, can still be affected, particularly when fires overlap with nesting, brood-rearing or molting periods.

The immediate impacts depend on where, when and how intensely a fire burns.

Most adult ducks can fly away from advancing flames. Nests cannot. Eggs may be destroyed if fire passes through nesting habitat, and newly hatched ducklings can be particularly vulnerable because they cannot yet fly. Even when birds escape the fire itself, they may be displaced from nesting, feeding or resting areas and forced to move to other habitats while conditions recover. Wildfire smoke may also affect birds even when they are not directly threatened by flames, potentially influencing their movements and use of habitat during major wildfire events.

Timing matters. A wildfire during spring or early summer may affect active nests and broods. Later in the season, many young birds have already fledged and adults are more mobile, potentially reducing some direct impacts.

A future shaped by fire and drought

Wildfire is not the only challenge facing waterfowl.

These changes are occurring against a backdrop of a warming climate. Canada is warming at roughly twice the global average rate, while parts of the Arctic are warming nearly four times faster. As temperatures rise, drought, wildfire and other climate-related pressures are reshaping many of the landscapes that waterfowl depend on.

Drought and wildfire are closely linked. When wetlands shrink and water levels decline, ducks have fewer places to breed, feed and raise their young. Reduced wetland habitat can lead to lower nesting success and lower duck production. The same dry conditions can also increase the likelihood of large wildfires across the landscape.

Longer fire seasons may also increase the likelihood that wildfires overlap with critical periods in the waterfowl life cycle, including nesting, brood-rearing and molting. Together, longer fire seasons, more frequent droughts and increasingly severe wildfires may create challenges that differ from those experienced in the past.

Why wetlands matter

Wildfire can dramatically alter habitat conditions, but not every part of a burned landscape is affected in the same way.

Some pockets of habitat remain unburned or only lightly affected during a wildfire. These areas, known as fire refugia, can provide shelter for wildlife and help ecosystems recover after disturbance. Research in western Canada has found that wetlands can contribute to the formation of these refuges, particularly in boreal landscapes. By retaining water and creating wetter conditions on the landscape, wetlands may help some areas remain less affected during wildfire and support recovery afterward.

Wildfire will always be part of Canada’s story. As fire seasons continue to change, wetlands will remain an important part of the landscapes that support waterfowl and countless other species.

Healthy wetlands store water, support biodiversity and help sustain resilient landscapes. Maintaining a diversity of wetlands and surrounding habitats can help ensure waterfowl have places to settle, feed, nest and rest if some areas are affected by fire. As Canada adapts to longer fire seasons and a changing climate, these benefits will continue to support waterfowl and the habitats they depend on.

Curious to learn more about ducks and DUC’s science? Check out the Duck Doctors playlist on our YouTube channel and dive into more of the science behind wetlands, wildlife and the species we love.