Ask A Researcher

Do you have questions about Adelie Penguins? Search this list of previously asked questions by students and adults from all over the world.

Nests and Chick Rearing
1. How long does it take to hatch the egg after it is laid?

Most eggs take about 34-35 days to hatch. The first egg laid takes about a day longer to hatch than the second egg (33 days). They hatch about 1.5 days apart.

2. How many eggs does the Adélie Penguin lay?

Most commonly, the nest of Adélie Penguins have two eggs. The females lay them about three days apart. The female will lay a third egg if the first one is lost, before the second is laid.

3. Do penguins return to the colony they were hatched in to raise their own chicks?

Under normal conditions, most Adélie Penguins build their nests within about 100 meters of where they began their life as a chick. If conditions for a colony become really, really unfavorable (access to colony blocked by an iceberg, for example), these penguins will search for colonies where conditions are easier.

4. Why do the penguins leave their young, when predators can come and take their young?

The adults guard the young on the nest and take turns foraging for food. By the time the chicks are 3 weeks old they are too big to be in the nest. The parents then leave, and the chicks form groups with other chicks called crèches. At this time both parents must forage for food because the chick pesters them to be fed.

5. How do the penguins build their nests?

When a male arrives at the colony in November, he scratches a bowl using his feet, and then gathers about 100 small rocks to elevate the bowl. Members of the pair guard the nest against other birds who will try to steal the rocks. When the male is incubating the eggs, the female gathers rocks.

6. Do the parents take turns watching the nest or does only the male stay and keep the eggs warm? Do the parents ever leave the nest unguarded? What is the size of the egg?

After the female lays the eggs, she will return to the ocean to feed and replenish her body weight. The male will sit on the nest until she returns. They will then take turns incubating (sitting on the eggs) until the eggs hatch. The egg can not be left unguarded because of the cold weather here and the Skuas who are always on the look out to snatch an unguarded egg, which they will eat.
Each egg is about the size of a goose egg; thus a bit larger than that of a chicken.

7. How do female penguins know when to come back to their nests?

They come back when they have recovered their body condition (became fatter) and are no longer hungry.

8. Why do the male penguin nest the egg instead of the female penguin,and how long does she remain gone?

Both parents take turns sitting on the egg. Normally, the male takes the first shift as the female has lost considerable body weight during egg production and must feed. Sometimes the female takes the first shift.

9. What do the Adelie penguins do with their eggs or newborns if they freeze when passing the eggs back and forth from parent to parent?

Adelie penguins do not pass the egg or the chicks back and forth, they take turns sitting on the nest and keeping the egg and chick warm. Exchanges happen in a few seconds because they do not want the egg or chick to freeze, or the Skuas to grab it.

10. Why do penguins hold there eggs on there feet and how big is an egg?

Adelie penguins shuffle their feet under the egg, forcing it into the featherless patch on their abdomen, called the incubation patch. The egg is the size of a goose egg, bigger than a chicken egg.

11. Where do penguins make their nest? (Christina, PA)

Adelie penguins make their nests in areas where there is no snow or ice and lots of small rocks for building nests.

12. Why is a group of baby penguins called a Creche'? (Jackson, IL)Goes Here

Creche is a French word meaning crib, but it also has the meaning of day nursery. The name was applied to groups of penguin chicks by French biologists in the early 1900s.

13. What would happen if a male or female dropped the egg, would a Skua get the egg or would it harm the chick? (Cassidy, IL)

Skuas are always looking for an unattended egg or chick. The fly over the colony constantly.

14. How hard are penguin egg shells? (Sierra, IL)

Since the nests are made of rocks, the shells have to be pretty hard, harder than a chicken’s.

15. Why do the penguins have their eggs in a deep ditch?(Elizabeth, IL)

Adelie penguins lay their eggs in a nest made of rocks usually on higher ground so that if the snow melts, the eggs will not get wet.

16. Why don't penguins have feathers on their "incubation patch"?(Brianne, IL)

There are not feather in the incubation patch so the egg or the chick can be against the warm skin of the parent.

17. How long does it take for a penguin's egg to freeze if the parents are switching on the nest? (John, CA)

A penguin egg will freeze in about 5 minutes if the temperature is near to 0. The parents switch in only a few seconds.

18. Why did the male in nest #13 leave the female with the eggs for 13 days without changing guard? (Sierra IL)re

The male was out foraging for food and must have been out a long way. 13 days was a long time, but at least he did come back, As you can see the egg was not a viable (able to hatch) egg, so that nest has been lost.

19. Do penguins seem to mourn the loss of a chick? (Mrs Schaefer, IL)

The penguins fight fiercely to protect their chicks, but when the Skuas do get them, it seems they recover in a few hours and go on about their lives.

20. How do the penguins keep their babies warm without squishing them? (Samantha, MO)

The chicks fit into an incubation pouch on the belly of the adult. It is a place between the feathers and is a bare patch of skin which is warm. When the chicks are too big for that, the adult stands over them rather than lay on them.

21. What do the babies eat? How do they eat? Do both parents feed them? (VT, 1st gr)

The parents regurgitate food for them from their stomachs. It can be fish, krill or squid. Both parents bring food back to the nest to feed the chicks.

22. How do you determine the sex of the chicks? (Linda, PA)

We can not determine the sex of the chicks. When we band them and someday they return to the colony as adults, by their behavior we will learn what sex they are.