DIFFERENTIAL GROWTH OF KING PENGUIN CHICKS IN RELATION TO DATE OF HATCHING

We fitted growth curves to mass, culmen, flipper, and foot measurement s from 52 King Penguin (Aptenodytes patagonicus) chicks from 1984 (N = 175 data points), and 53 chicks from 1989 (N = 162 data points), from the Archway Bay colony, Marion Island, Prince Edward Islands group in the southern Indian Ocean. Early-hatching chicks (before 7 February) appeared to grow more slowly, but still had sufficient time to achieve near-adult proportions and gain mass before the onset of the winter f ast (early June). This presumably improved their chances of surviving the 3 - 4 month period of either little or no food. Despite showing a trend towards faster growth rates, chicks hatching after 7 February we re smaller at the onset of fasting, and did not gain additional mass. Culmen growth continued throughout the fledging period, but was slowes t during fasting. Chicks surviving the winter period had greater pre-f ast body masses than those that died; a mean of 41.3% of peak pre-fast body mass was lost by survivors before feeding recommenced. Some adul ts appeared to be better quality provisioners of chicks, as evidenced by certain chicks with similar hatching dates being fed for a longer p eriod before winter, and some chicks being fed at least once during wi nter. Also, some chicks had relatively high pre-fast and fledging mass es.