During breeding, emperor penguins have to forage in remote ice-free areas. Therefore, penguins that have lost their chick during a foraging trip still maintain high residual PRL levels and this, combined with colonial breeding, probably facilitates kidnapping.
If a female emperor penguin can’t procreate, she’ll sometimes resort to stealing a chick from another penguin to satisfy her mothering instincts. As National Geographic details, this ordeal is even less fun for the chick than it sounds.
Why do Penguins give birth to babies?
The cause seems to be the unusual hormonal chemistry of emperor penguins. The female birds produce a certain hormone, called prolactin, involved in parental behavior.
One question we ran across in our research was “Why do penguins lay eggs on their feet?”.
Males keep the eggs on their feet, but they do not sit on it. Males balance the eggs on their feet and save them from the cold ice. Males also carry the baby Emperor penguin’s eggs in their breeding pouch which has insulating feathers. During this baby-sitting male penguins fast and they do not consume anything at all.
Basically, penguins are forced to spend their lives like Goldilocks’ first two bowls of badly cooked porridge, without ever finding the “just right” spot they must be desperately craving. When you visit penguins at the zoo, they’re usually behind glass, and there’s a good reason for that., and penguins stink.
The female birds produce a certain hormone, called prolactin, involved in parental behavior. But while in case of most birds the levels of prolactin drop when the eggs are removed from them even before they hatch, in case of penguins the prolactin levels remain high for a long period.
Adélie penguins are one of the few penguin species to use rocks when building their nest. “They will collect a lot of rocks to elevate the egg because, when snow starts to melt, if the egg is right on the ground it will drown,” de, and napoli said.
Do hormones affect chicks’kidnapping behavior?
The result was that the birds with lower levels of prolactin were found to be four times less likely to kidnap chicks. The hormones do not, however, directly determine the behavior – they only increase the probability for certain behaviors to be expressed.