Nesting Time Activity

At the end of this activity you will be able to answer these questions:

1. Who spends more time on the nest, the female or the male Adelie Penguin?
2. Do all nesting adults spend the same amount of time brooding (time on the nest) and foraging (out looking for food)?
3. Why does the duration of feeding trips decrease as the season progresses?

Background information

Adelie penguins raise their chicks on snow-free land which has a supply of small rocks used to build their nests. The open ocean is usually many kilometers away at the beginning of the season and the Adelies must walk over the sea ice to reach the land when breeding time begins. As temperatures warm the sea ice disappears making the open ocean, which is their food source, much closer. At no time will Adelie parents leave their eggs unguarded. Even a few minutes in the cold air of Antarctica would freeze them. Plus ever-watchful predatory birds, Skuas, would quickly take any unguarded egg for a meal. When the chicks hatch there will always be a parent guarding them until the chicks are old enough to keep themselves warm by huddling and large enough to standup to a Skua.

Both parents have reduced their body's reserves in walking the distance across the sea ice to build the nests and lay the eggs. But always one must stay on the nest. This activity will allow you to chart how long each parent is on the nest, and how long they are away on foraging trips. Each trip requires the penguin to walk over the ice to the open ocean, feed and then return to the nest.

Directions

Select a nesting pair from the Nest Check activity at penguinscience.com/education/nest_check. Everyday, record in your field journal whether the female or the male is brooding the eggs or guarding the chicks. You will see that sometimes both adults are near the nest, record that as both present. Make up your own table or chart to record these data, using the one below as an example.

Nest #8 Time on the nest for the female and the male.

KEY

Continue recording who is on the nest until the day comes when both parents are out foraging on the same day. At this point the chicks are able to fend for themselves against the Skuas and the cold by forming groups called crèches. The chicks demand a great deal of food during this time, so it requires both parents be out foraging at the same time. This way, the chick gets almost twice the amount of food it would otherwise receive.

Data Analysis

1. Determine the number of days each parent was a) on the nest and b) out foraging. Create a visual way to share this information with your classmates. The above example is only one way. Be creative.

2. Compare your data with other members of your class who selected different breeding pairs. Are they the same? If they are different come up with some reasons why they are different.

3. In your groups answer the questions listed above at the start of this page.