Following the request of the Scientific Committee of CCAMLR to conduct sensitivity analyses on existing data regarding predator breeding biology parameters, this report presents such a treatment of data obtained at the Magnetic Island Adélie penguin colony in Prydz Bay in the 1987/88 and 1988/89 breeding seasons.

The data on the following parameters were analyzed:

• adult weight on arrival at breeding colonies;
• duration of first incubation shift;
• duration of adult foraging trips;
• breeding success; and
• chick fledging weight.