The prey species are selected for their key positions in Antarctic ecosystems and where the potential harvest would have a major effect on the marine system (Kock 2000). A number of parameters are monitored for each species reflecting the potential to respond to changes in the availability of prey or environmental factors. The CCAMLR has produced a set of standardised monitoring procedures that are used by participating member states across a series of Integrated Study Regions (ISR) where interactions between predators, prey, fisheries and the environment are examined in detail. This concept is the focus of current and future discussion within the Working Group on Ecosystem Monitoring and Management (WG-EMM).