Many data on the diets of important vertebrate predator species in Prydz Bay and around the sub-Antarctic Heard and Macquarie Islands have been collected during the last seven years. Published and unpublished results are collated and summarised, and several important points emerge.

In Prydz Bay, on which is cantered the CCAMLR Ecosystem Monitoring Programme's priority study area, Euphausia superba forms a rather low proportion of the diet of most vertebrate predators. Euphausia crystallorophias and the fish Pleuragramma antarcticum are important in most diets, and many predators can switch between prey species. The use of these predators to monitor the state of prey populations is thus very limited, although continuing studies will be useful to assess the natural variability of the system.

Around the sub-Antarctic islands, the four penguin species feed more heavily on fish, especially myctophids, than at other comparable localities.