Duckling body mass increases with abundant aquatic invertebrates

New research by PhD candidate Basile Marteau shows that mallard ducklings gain more weight when foraging in temporary ponds than in lakes—thanks to higher insect availability. This study highlights the ecological importance of seasonal wetlands for waterfowl development and conservation planning.

At the University of Helsinki’s Lammi Biological Station, PhD researcher Basile Marteau conducted a study examining how the availability of aquatic insects affects the growth of mallard (Anas platyrhynchos) chicks in different wetland types. The research focused on understanding the role of temporary wetlands—such as seasonal ponds—in supporting wildlife, particularly waterbird chicks during the breeding season.

 

Chicks were allowed to forage either in permanent lakes or in temporary ponds formed by seasonal fluctuations. Their weight gain was monitored over four-hour periods. The results revealed that chicks grew significantly faster in the temporary ponds, where large aquatic insects were more abundant. These findings highlight the crucial role of diverse wetland habitats in supporting early development and survival of waterfowl.

“Temporary wetlands are often overlooked, but they offer key foraging grounds, especially for species like mallards during the critical early life stages,” Basile explains. “This study shows how important it is to protect and restore these habitats, which are essential for the biodiversity of boreal ecosystems.”

The research also emphasizes broader conservation concerns. The drainage and loss of wetlands can reduce foraging opportunities for birds and lead to declining populations. By demonstrating a direct link between wetland type and chick growth, the study provides valuable insights for land-use planning and waterfowl conservation.

Lammi Biological Station played an essential role in enabling this work. “The station has the perfect infrastructure for ecological fieldwork and is located near a diverse landscape, including the Evo Natura 2000 area,” says Basile. “I’ve lived and worked here for about a year and a half during my research, and the supportive staff and facilities have made the experience smooth and enjoyable.”

Originally from Paris, France, Basile completed his Master’s degree in Angers before starting his PhD in Finland. His research centers on how wetland dynamics affect wildlife—including birds, bats, and aquatic invertebrates. He strongly recommends Lammi to other researchers: “Finland is ideal for ecological research, and Lammi in particular allows for deep exploration of boreal ecosystems.”

His message to aspiring scientists? “Only pursue a PhD if you know why you're doing it and have a good team around you. It’s a rewarding path if you’re passionate—but it shouldn’t be a default choice.”

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