Nineteen cases of physical deformities, colour aberrations, and unusual eggs were recorded in emperor penguins (Aptenodytes forsteri
) and Adélie penguins (Pygoscelis adeliae
) from the Haswell archipelago in the Davis Sea, East Antarctica, during 1956–2016. Two very small eggs and one very large egg were recorded from emperor penguins, and two very small eggs from Adélie penguins. Physical deformities included beak deformities in two emperor penguin adults and two chicks, and two chicks had deformed spines. Colour aberrations included the ino mutation in a juvenile emperor penguin, and examples of dilution (two cases), progressive greying (two cases), and isabellinism in adult Adélie penguins. Feather-loss disorders were recorded in two downy emperor penguin chicks. Data on the occurrence of identified abnormalities and disorders are given. These cases provide a baseline for assessing changes in the frequency of physical abnormalities in these Antarctic penguin species.