Temporal variability and the interrelationships between CEMP parameters collected on Adélie penguins at Béchervaise Island
Temporal variability in a series of CCAMLR Ecosystem Monitoring Program (CEMP) parameters and the interrelationships between these parameters were examined for Adélie penguins over a period of 12 years. Data were collected from 1990/91 to 2001/02 at Béchervaise Island, Eastern Antarctica. Parameters relating to chick survival (brooding nest counts, counts of chicks when two-thirds were crèched and fully crèched chick counts) display large temporal variability while other parameters, such as arrival counts and incubating nest counts, are more stable between years. The low degree of correlation between parameters collected before incubating nest counts with those collected after brooding nest counts reinforces the notion that events occurring during the hatching
period are critical for chick survival. There was a strong negative correlation between female foraging trip duration during both the guard and the crèche period and breeding success, while the correlation between breeding success and foraging trip duration was low for males. Male foraging trips during the crèche period were, however, moderately correlated with fledgling mass.
Within-season penguin weights, the simplest output from the Automated Penguin Monitoring System (APMS), were also examined in terms of their correlation with breeding success. Results indicate that low weights of females at the time they depart after egg laying appears to be the fi rst indication that a season may have low breeding success. The results obtained throughout these analyses indicate that knowledge of the sex of birds can be important for understanding breeding success and the interrelationships between CEMP parameters.