Young Birds Perfect Their Migratory Behavior Through Learning and Exploration, Research Shows
Michelle Milliken
Billions of animals migrate each year, but there’s limited information on how most species’ migratory behaviors change as they age. While time and energy concerns are typically the focus of studies on migration, new research finds that learning may also play a big role.
Scientists from the University of Wyoming and the Max Planck Institute of Animal Behavior recently shared the findings of seven years’ worth of research into white stork migration in southern Germany and Austria. The team followed birds from their first migration onward to see how their behaviors shifted in subsequent years. Understanding these behaviors gives important insight into how migratory animals, which face increasing threats to their survival, may or may not adapt to a changing world.
The team had hypothesized that younger birds learn to shape migration as they age, which would mean they’d start by exploring and mature into more direct routes. Their findings, published in Proceedings of the National Academy of Sciences, backed up that theory. Among the 250 white storks tracked, young birds tended to reduce their energy during their first migration, going to new places and discovering shortcuts. However, on subsequent journeys, they upped their energy expenditure to get to their destination more quickly and directly.
The team says these patterns may come about due to younger birds needing to save energy on their riskier first trip, while getting to their destination faster may allow older birds access to better breeding territory and improve the chances of reproductive success.
The findings suggest that learning and exploration in early life are key to perfecting migration patterns. There is the chance that genetics impact the information birds have, as well, but it seems there’s more to it than that.
The authors write, “Whether the first migration is guided by genetics or results from following informed individuals, learning within a lifetime represents an additional and complementary mechanism shaping animal migration. There is evidence that even when the initial migration direction appears genetically encoded, increased experience and learning can improve migratory performance.”
With the apparent learning of shortcuts, there’s also evidence the birds use spatial memory as part of their information gathering process. This could also mean the animals use a cognitive map for navigation, but the researchers say social facilitation or environmental conditions could also impact their paths.
The authors write, “Further research is needed to determine whether the shortcutting we document is the result of social transmission of more direct movement paths or large-scale cognitive maps, similar to those discovered in bats. Regardless of the exact mechanism responsible for the innovation of spring migration shortcuts, the incremental straightening of the migration route over time is evidence of a switch from exploration to exploitation, which highlights the critical role of spatial memory.”
Regardless of how these behaviors are formed, more research into migratory species may be needed, as many face the threat of extinction. According to a recent report from the UN biodiversity treaty The Convention on the Conservation of Migratory Species of Wild Animals (CMS), 44% of CMS-listed species are experiencing population declines, and 22% are threatened with extinction. You can read more on that here.
