This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
King penguins are pretty social animals. Not only do they tend to hang out in a big group, but even within the group, they form little sub-groups; cliques of penguins who like to hang out together. In case this couldn’t get any cuter, their chicks also hang out in groups without any adult penguins around. Oh wait, it can get cuter; the technical term for the group of penguin chicks hanging out together is a ‘cr?che’. Sometimes cr?ches get broken up, or get mixed with other cr?ches. Perhaps when a predator attacks the group and throws the penguin chicks into flappy disarray. The chicks are then faced with the task of getting back to the right place in their colony so that their parents can find them again.
When chicks get lost they are generally pretty good at finding their way back to their colony, especially during the day. Scientists proved this by building an arena 100 metres away from the colony, taking a chick and putting her in the arena. The chick waddled over to the side of the arena closest to its colony, thus showing the scientists that she knew perfectly well where her colony was. When the scientists moved the chicks to the arena at night it was harder for them to find their way to the correct side of the arena, but if the wind was blowing towards them they could, presumably because they could either hear or smell their colony. And before you start feeling too bad for the chicks, they were never taken out of their cr?ches for more than 90 minutes and as parents only come and feed their chicks every few days they were unlikely to be too worried about a missing chick.
Now, the chicks in a single cr?che aren’t all exactly the same age, and some have more experience than others. Therefore, it seems that if the cr?che were to become displaced from the rest of the colony it might make sense for the younger, less experienced chicks to take a lead from a more experienced chick. To find out if this was the case, a recent study by Nesterova and colleagues created groups of chicks and then got them lost to see what they would do.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
To make a mini-group of penguins for the purpose of the experiment, the scientists put two chicks together. In one group, both of these chicks were na?ve, while in another group, one chick was na?ve and the other was more experienced (as much as a king penguin chick can be, I assume). The main difference between the na?ve and experienced penguin chicks was that the na?ve chicks had never had to navigate their way back to their colony before, whereas the experienced birds had gotten lost and found their way home before. I know which penguin chick I’d rather be paired with.
The researchers then picked up the two chicks, blind-folded them, turned them around three times and put them in the enclosed arena. After 10 minutes in the arena, the door was opened and the chicks were allowed to try to return to their colony.
The scientists found that when they released a pair of chicks where one was experienced and one na?ve, the experienced chick was faster at getting back to its home cr?che back in the colony than was the na?ve chick. What’s more, the experienced chick in the pair would tend to take the lead, with the na?ve bird waddling behind it. The experienced chick didn’t seem to wait for its na?ve buddy: it walked home just as quickly as when the scientists released it by itself, often leaving its na?ve partner behind. The na?ve chick could choose to follow its experienced partner or not, and when it didn’t it didn’t do so well: it took longer to get home and was more likely to get lost. It also did a lot worse if it was released by itself, wandering around for much longer than if it had an experienced chick with it to follow home.
This study clearly shows how experience is important for chicks in finding their way home if they get lost. It also shows that the experienced chick’s number one priority was to get back to its colony rather than to stay with its new na?ve chick pal, even though one might have thought that this might be better for predator defence (and maybe just to have a friend to walk with). Interestingly, when both chicks were na?ve, they took it in turns to lead and to follow when trying to find their way home. And, before you ask, all chicks were reunited with their home cr?ches at the end of the experiment. A video of the experiment can be seen here:
Photos Credits
Penguin chick 1: Liam Quinn
Large group of penguins and penguin chicks 2: David Stanley
References
Nesterova, A. P., Mardon, J., & Bonadonna, F. (2009). Orientation in a crowded environment: can King Penguin (Aptenodytes patagonicus) chicks find their creches after a displacement?. Journal of Experimental Biology, 212(2), 210-216.
Nesterova, A. P., Flack, A., van Loon, E. E., Bonadonna, F., & Biro, D. (2015). The effect of experienced individuals on navigation by king penguin chick pairs.Animal Behaviour, 104, 69-78.