Researchers solve mysteries around penguin navigation
EU-funded PENGUINAV was the first-ever study of how groups of king penguin chicks find their way home. We now know more about collective animal movements and how to study the movements of other species.
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King penguins make excellent subjects to study animal navigation, which has attracted much interest in behavioural science in recent years. “King penguins, especially chicks, have a clear tendency to group and a strong motivation to return to their place within the colony,” explains research fellow Anna Nesterova, who led the study of group dynamics and navigation in king penguin chicks (PENGUINAV). A colony of king penguins can stretch over 1 km on the beach and be home to more than 260 000 breeding pairs. As predators and adverse weather conditions can displace penguin chicks, it is essential that they know how to return so that their parents can feed them.
In one of the experiments, PENGUINAV researchers displaced pairs of penguin chicks from their crèches (groups of chicks) in the Ratmanoff colony on the remote Kerguelen Archipelago in the southern Indian Ocean. They then tracked them with mini-GPS loggers. In another experiment, the researchers used time-lapse photography to study the natural movements of hundreds of penguins.
The findings provided:
Chicks prefer to walk home with a friend if possible
Displaced king penguin chicks can find their way home day and night. Unlike a human toddler easily lost in a huge crowd, king penguin chicks confidently waddle along the beach to their crèche among thousands of other penguins and wait for their dinner.
“Penguin chicks don’t like to be alone due to the risk of predation,” explains Nesterova. In fact, the chicks navigated well in pairs. In some cases, they took turns to lead. When both chicks in a pair were from the same crèche, they ended up closer to their original spot than chicks from different crèches. Chicks do think for themselves however. And even though they like to be in a group, getting to their destination is an overriding factor. Chicks from different crèches were seen to split up at some point along their return journey to ensure they got to the right place.
Remote field studies — an achievement in cross-border coordination
Few researchers have the funding and the resources to conduct field studies like PENGUINAV. The team was able to observe what animals do in nature as opposed to a laboratory. The expeditions to penguin colonies required extensive logistical support — the transportation of researchers, supplies and equipment over land and sea. It was funding from the Marie Skłodowska-Curie Actions and the Institut Polaire Français Paul-Emile Victor that made these expeditions possible.
PENGUINAV involved British, French, and German research laboratories and established new collaborations in the Netherlands, Germany, and Hungary. Nesterova continues to conduct further studies with researchers from those countries.
From penguins to other species
PENGUINAV used a combination of GPS technology and time-lapse photography to track group movements in the king penguin colony. For the first time, the researchers obtained detailed data on the collective movements of king penguins. In future, researchers could use time-lapse photography to learn how colonies change.
Most penguin colonies don’t have an electricity supply, making it challenging to run time-lapse observatories all year. In windy, icy conditions, troubleshooting equipment problems also becomes a challenge. The technology must operate unattended for a long time in harsh weather, but also be easy to fix. “Each year, we have learned from our experience with the equipment and continue to improve it with our German partners at the Alfred Wegener Institute, to make it more robust,” says Nesterova.
Better understanding of the group movements of king penguins is not the study’s only interesting outcome. Although the number of king penguins is increasing, the study’s findings, methods and technologies could also be applied to endangered species in habitats that are hard to reach. This could help future conservation efforts.