Dion Pretorius
Dion Pretorius is Communications and Policy Manager at Science & Technology Australia.
Changes in the climate are apparent across the globe, but the impacts are acute in Antarctica. The Southern Ocean is home to an ecosystem that helps regulate the world’s climate, contains a diverse range of species, and will play an increasing role in supporting global food security.
However, this ecosystem is changing in response to global warming, ocean acidification and human activities, and the challenge is on to understand and manage these shifts in time to avoid irreversible change.
Jess Melbourne-Thomas is a biologist with the Australian Antarctic Division, based in Hobart, Tasmania, and a lead author for the recent Intergovernmental Panel on Climate Change (IPCC) report on ocean and polar response to climate change.
She heads a project through the Antarctic Climate and Ecosystems Cooperative Research Centre that uses ecosystem models as virtual laboratories to help understand how these systems function and how they might change in the future.{%recommended 5732%}
“These ecosystems have been difficult to model, but with improved computing power and better understanding of the food webs in the Southern Ocean, we are now starting to map out possible futures for the region,” she says.
One of Melbourne-Thomas’ PhD students, Stacey McCormack, is working with her team to evaluate the structure of Southern Ocean foodwebs, and in particular to better quantify the role of Antarctic krill in supporting penguins, seals and other predators.
“Antarctic krill have conventionally been seen as a keystone species supporting foodwebs in all parts of the Southern Ocean,” McCormack explains.
“Our work is using a large database to explore how well this paradigm holds in practice. Our results will be really important for informing management of Antarctica’s krill fishery and for understanding ecosystem responses to climate change.”
Melbourne-Thomas says that models can also be used as flight simulators to help test alternative policies and management approaches to achieve sustainable management of the Southern Ocean.
“Modelling was one of four themes discussed at the recent Marine Ecosystem Assessment for the Southern Ocean (MEASO) conference that we hosted in Hobart,” Melbourne-Thomas says.
“Over 180 scientists, marine policy-makers and fishers gathered to take a holistic view of the issues facing this important region.”
She describes the event’s unique Policy Forum, which brought together a broad range of stakeholders and provided an opportunity to discuss linkages between science and policy, as a particularly successful component of the conference.
“We are at a critical point in Southern Ocean ecosystems research and management where we need to be factoring climate change effects into decision making for marine living resources,” she says.
“Antarctica is likely to bear the brunt of displaced fishing effort from other regions, and may face large-scale extinctions as a results of ocean warming.
“We need to take a “whole-of-system” approach to ensure that the valuable ecosystem services provided by life in the Southern Ocean can be maintained into the future.”
Jess Melbourne-Thomas and Stacey McCormack are among 30 Superstars of STEM featured in this weekly series, prepared by Science and Technology Australia. To learn more about the program, visit the STA website.
