Adelie penguin weights before and after foraging trips from three groups of penguins: control, single egg removed and penned females

As an index of physiological condition and success of foraging, penguins were weighed early in the season when they were flipper banded and then re-weighed when they returned from their foraging trip. Three groups were compared: a control group that was left undisturbed except for the weighing, the removal group which the first egg from the nest was removed and the penned group where the female were prevented from going to sea for their first foraging trip by being placed in a pen for 4 days. These observations will contribute to the determination of any annual fluctuations in the success of penguin foraging.