Environmental issues in Antarctica

State of the Environment 2011 Committee. Australia state of the environment 2011.
Independent report to the Australian Government Minister for Sustainability, Environment, Water, Population and Communities.
Canberra: DSEWPaC, 2011.
At a glance
As in other regions, the key risks to the Antarctic environment are being brought about by human activities often far away, including global population and economic pressures, and the effects of climate change.
While management can mitigate many of the population and economic impacts, climate change will be the main and uncontrollable driver bringing about change.
It is clear that Earth's polar regions are likely to be affected severely by changing climate conditions. These changes represent the highest risk to the region, since they are unlikely to be mitigated by any management measures. The impacts of climate change on the Antarctic environment are detailed in Sections 2 and 3 of this chapter.
Population and economic growth are leading to other risks. Remaining fish stocks around the world are highly depleted and appear largely unable to recover. With a growing human population demanding a new source of protein, the pressure on the industry to catch krill is likely to increase. A rapidly expanding krill fishery will have a considerable environmental impact and is a risk, particularly if the fishery expands at a rate that outstrips the ability of CCAMLR to manage it. In the past, the fishing nations that are active in the Southern Ocean had never reached the catch limits set by CCAMLR. However, in the 2009-10 season, the fishery reached the 'trigger level' in one of the subareas in the South Atlantic and the fishery was closed for the first time. Newly developed technology has allowed the vessels to catch about 800 tonnes per day compared with about 400 tonnes landed by 'old style' vessels. This advanced fishing technology has contributed to the rise in the krill catch to 210 000 tonnes in 2009-10 and high catch rates may force the krill fleet to expand into new areas to avoid exceeding the existing catch limits.
The consequences of krill fishing continuously operating at the catch levels set by CCAMLR are as yet unknown. The impact of environmental changes on the krill population, such as ocean acidification, will also have to be taken into account in the process for calculating precautionary catch limits for Southern Ocean fisheries.