Southern Ocean ecosystems: Environmental change and conservation
Like marine ecosystems world-wide, the Southern Ocean faces many threats and conservation issues as a result of physical, chemical and biological changes. These changes are already occurring and will continue to occur because of fishing, climate change and ocean acidification. Changes to Southern Ocean ecosystems have consequences for the global carbon cycle, the conservation of threatened and depleted marine species and for the sustainable exploitation of fisheries.
Scientific research under this theme is helping scientists understand the impact of global change on Southern Ocean ecosystems, the effective conservation of Antarctic and Southern Ocean wildlife and the sustainable, ecosystem-based management of Southern Ocean fisheries.
The research is divided into four streams:
- Marine ecosystem change
- Wildlife conservation
- Southern Ocean fisheries
- Protecting marine biodiversity
The health and conservation of Southern Ocean ecosystems is important to a number of international treaty bodies and inter-governmental initiatives, including the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), the International Whaling Commission (IWC), Agreement on the Conservation of Albatrosses and Petrels (ACAP), the Australian Fisheries Management Authority (AFMA) and the Intergovernmental Panel on Climate Change (IPCC). This theme will address strategic needs identified by these peak bodies, as well as national priorities.
Photo: Keith Martin-Smith
The research will:
- Improve understanding of the impacts of ocean acidification on selected biota and ecosystems of the Southern Ocean, including assessment of their resilience to predicted change scenarios.
- Identify sensitive marine indicator species or systems for tracking and understanding the impacts of environmental change.
- Assess the risks of global change impacts on Southern Ocean ecosystems and species of high conservation or fisheries value. This includes evaluating the probability of different food web structures arising under predicted changes in the ocean and sea ice systems.
- Improve knowledge about the status and trends of important Antarctic wildlife populations (whales, seals and seabirds), leading to improved conservation planning and management measures.
- Improve scientific information for fisheries managers (including strategies to reduce bycatch) and integration of fisheries data into ecosystem models to assist in management decisions.
- Design a comprehensive, adequate and representative network of spatial management areas. These include marine protected areas in the Southern Ocean (and within the CCAMLR Area), particularly focusing on the marine biodiversity in the waters off East Antarctica.
Monitoring of key ecosystem components is a fundamental part of this research theme. For the past 20 years the Australian Antarctic Division’s Southern Ocean ecosystems research has supported a number of strategic monitoring initiatives for individual species, communities and whole ecosystems. These include plankton surveys, underway sampling from research vessels, land-based monitoring of Adelie penguin populations, and fish and baleen whale population surveys. Data from this work will provide the foundations for analyses for the first few years of the science strategic plan. The results of these analyses will guide future monitoring programs.
Theme leaders: Dr Andrew Constable and Dr Bill de la Mare
Dr Andrew Constable - Southern Ecosystems Change Theme Leader
My name is Andrew Constable. I am a theme leader in the Australian Antarctic science program responsible for studying Southern Ocean ecosystems and that theme has a number of elements. The first element is to understand how southern ocean ecosystems are responding to climate change. The second thing is to look at how do we conserve whales, albatross and other species like that? And then a big responsibility is how do you manage fisheries in the Southern Ocean so as they remain ecologically sustainable?
One of the main parts of our work is to do field work in the Southern Ocean. That involves going to sea on ships for maybe up to three months at a time and what we try to do there is we are sampling the animals and plants in the ocean to better understand how they work with the ocean, what sort of impacts changes in the ocean might have and in particular what things might happen as a result of climate change.
The last thing that we do is we try to look at undertaking laboratory studies that help us better understand the exact mechanisms of impact. That is how we know about the effects of acidification on krill, for example. That was done here at the Australian Antarctic Division.
For example we know the Southern Ocean ecosystem is becoming more acidic which there are some animals at the bottom end of the food chain, they’re not doing so well. So krill, for example, their embryos don’t survive very well in a super acidic environment.
One of the big challenges is being able to do science at a sufficiently large scale, so operating ships or being able to sample in many different places that give us very good information that we can feed into our models and basically help management make the right decisions.
The more we are able to forecast what is going to happen in the future, the more that we can adjust our management practices and the more that we can make better decisions in advance and make sure that fisheries remain ecologically sustainable.
I’m never bored. It’s a fantastic place to work, the work is very challenging, one of the great things about this work is the people that I work with. It is those partnerships that matter. That’s what makes the science very enjoyable and we can overcome the challenges together. In the end it will be a community enterprise to overcome these challenges and to better understand what we have in the future.