Last Sunday, Wouter Vansteelant painted a vivid picture of the challenges of young spoonbills for listeners of the radio program Vroege Vogels. “After the breeding season, the spoonbills seek each other out. We increasingly view these places with hundreds, thousands of spoonbills as meeting points rather than just foraging sites. Traveling groups form there, and all sorts of things are said to one another. To reach Africa, young spoonbills have to manage to join an early flock. It is quite possible that a youngster leaves earlier than its parents.”
If you dive into the bird migration literature, you will often read that young birds know where to migrate because they inherit a migration program from their parents. This deterministic view suggests that young birds either rely entirely on instinct or follow their parents to traditional wintering sites. Once they reached a destination, they were expected to return to the same place year after year, as if after the first migration, their behaviour became fixed. Never change a successful strategy, right?
But tracking studies of spoonbills are revealing a more variable development process. Young spoonbills leave the Dutch breeding areas on their first journey south each autumn. From breeding islands such as Griend, they head toward landscapes they have never seen before. Their routes are long, to unfamiliar destinations. Not all young birds reach warm southern wetlands during their first winter. Some remain in northern regions such as the Netherlands or France, where conditions can be harsh. If temperatures drop below zero, food can become harder to find, and survival becomes a daily challenge.
A few weeks ago, Wouter spotted a young spoonbill named Fury in southern Spain. Fury showed just how flexible spoonbills can be. She was fitted with a GPS tracker on Griend in 2024. During her first winter, she stayed in the Netherlands, searching for food in cold waters while strong winds swept across the wetlands. A year later, her journey took a very different turn. Her GPS track led far south to the famous wetlands of Doñana in southern Spain, where she joined dozens of other spoonbills feeding in rice fields rich with crayfish and other prey. The same bird that had braved through a cold northern winter now seemed much more comfortable in a warm and food-rich landscape.
Spoonbill in the Doñana region of southern Spain
Stories like Fury’s suggest that migration is not only guided by instinct but can also involve learning and exploration. Some birds improve their routes after early journeys and may travel farther in later years. It’s not clear why some birds stick to their first destination, while others try new tricks. But it seems likely that such late-life learning is helped by experienced birds, and that social learning allows migratory behaviours to spread through populations like traditions. “In that case, we can consider migration behaviour as a form of ‘bird culture’,” Wouter says.
Long-term research in the Netherlands shows that migration is more flexible than once believed. Studies of colour-ringed spoonbills reveal that up to a quarter of young birds shift their winter destinations after their first year, often moving farther south, while most older birds do remain faithful to familiar sites. These patterns raise new questions about whether migration shifts are shaped by experience, social learning, or environmental conditions. Thanks to citizen scientists and long-term tracking efforts by Werkgroep Lepelaar, NIOZ, and BirdEyes, researchers are uncovering how young birds learn their migration routes and showing that migration is a dynamic learning process rather than a fixed set of rules.
