Coastal waters along the Danco Coast, western Antarctic Peninsula, form a highly productive ecosystem that supports a high abundance of top predators. However, this region is experiencing accelerated environmental change, leading to significant changes in prey availability and food‐web structure. In this context, predator diets provide valuable indicators of ecosystem status. The diet composition of Antarctic shags ( Leucocarbo bransfieldensis ) during the 2018 chick‐rearing period at three breeding colonies was investigated through pellet analysis ( N = 91). Antarctic shags primarily consumed demersal–pelagic prey. Dominant prey species were Antarctic black rockcod ( Notothenia coriiceps ) and Dusky notothen ( Trematomus newnesi ), with colony‐specific variation. No significant changes were detected between chick‐rearing stages; however, a gradual decline in the number and mass of the N. coriiceps , and an increased contribution of smaller prey species, such as T. newnesi and H. antarcticus, was detected as the chicks approached fledging. The results are compared with previously published dietary data from the same area and discussed in relation to potential long‐term variability in prey availability and implications for ecosystem monitoring.
Marianela Beltrán (2026) studied this question.