The Antarctic (of which Australia claims 42%), and the surrounding Southern Ocean are arguably the most important, yet least observed of marine habitats. Connecting all the world’s oceans, the physical structure of the Southern Ocean profoundly influences world climate and ecology, and plays a key role in global warming. The merging of oceanography and marine mammal ecology advances our understanding of the world’s oceans and its top predators, and allow us to predict how these species will be affected by future global warming. As well, it will provide important data on ocean properties throughout the Antarctic winter – data currently unavailable but crucially important to climate scientists.

Seals are apex predators that are sensitive to changes in climatic variation and the distribution and abundance of prey. Their responses are manifest in changes in their foraging location, foraging success and reproductive output (Hindell et al. 2003). Therefore monitoring predator distributions at sea can provide information on the spatial and temporal variability of their prey and their environment.

As seals forage successfully they increase their stores of blubber, become more positively buoyant and change how they sink or float in the water. Change in the daily rate at which they sink or float, known as drift rate, can then provide a measure of biological productivity. The power of such an approach is that combining at-sea movements of multiple individuals enables identification of the importance of persistent and ephemeral hotspots of biodiversity in the Southern Ocean. This program is also highly complementary with ongoing monitoring of lower trophic level abundance in the Southern Ocean. This program is part of the Integrated Marine Observing System and observations of foraging apex predators may be used to direct oceanographic and biological sampling to form a multidisciplinary, process-oriented whole system approach to marine research.