Plenary Lecture by A/Prof Ceridwen Fraser: Southern Ocean Diversity and Connectivity

The David Walton Antarctic Science Lecture:
Assistant Prof. Ceridwen Fraser: Southern Ocean Diversity and Connectivity: Surprises and New Directions

The Southern Ocean surrounds Antarctica, with strong, eastward circumpolar currents and winds, and has been considered something of a moat, keeping the Antarctic biologically isolated from the rest of the world. Within the Antarctic, diverse endemic marine species flourish, many showing unique adaptations to their challenging environments. Interdisciplinary studies are, however, indicating that the Southern Ocean is frequently crossed by passively-dispersing organisms travelling thousands of kilometres from northern source populations. The unique ecosystems of Antarctica are therefore likely to have been more a consequence of environmental extremes in the region than of isolation. With warming, numerous sub-Antarctic or temperate species might establish in the Antarctic, even without human-mediated transport of organisms to the region. Our knowledge of native biodiversity in Antarctica has been hampered by the logistical challenges of sampling in rough, icy seas far from human settlements, and these large knowledge gaps create flow-on challenges for managing ecosystems at risk of rapid and dramatic change. This talk will look at progress in interdisciplinary studies of Southern Ocean connectivity, and outline directions for future research priorities.

Plenary lecture held at the 10th SCAR Open Science Conference (1-10 August 2022).