The quantity of litter in the world's oceans has been steadily rising as a result of river pollution and poor waste management in many areas of the world. Although it is the most isolated body of water on the planet, winds and ocean currents mean that the Southern Ocean is not exempt from this pollution, and debris is common on its waters and shores.
On the shores of the subantarctic islands, tonnes of waste (mainly plastics) are washed up every year. Remnants of fishing gear such as bait straps, ropes, nets, floats and buoys, and domestic rubbish such as bottles, bags, shoes, bottle tops and the like are, unfortunately, plentiful. Many of these are often mistaken for food by wildlife.
Recent research shows that the amount of debris on subantarctic islands is directly proportionate to the level of commercial fishing in the area. Strapping, nets and ropes entangle seals and penguins, and often lead to a slow and painful death. Small floating plastic fragments, such as polystyrene beads and chips, can be mistaken for food by surface feeding birds. Its frequent ingestion results in death. Oil and chemicals spilled into the Southern Ocean's cold waters may take many years to break down, and can cause irreversible harm to the seals, penguins, and other wildlife living on its shores.
All of Australia's continental Antarctic stations have waste water and sewage treatment equipment which minimises the effects of waste dispersal into the sea. The volume of effluent released, its Biological Oxygen Demand (an estimate of the numbers of micro organisms) and suspended solids (to estimate the amount of organic matter) are constantly monitored. Sludge from the plant is removed to Australia, and the AAD is currently trialling UV sterilisation of the remaining effluent.
As a signatory to the Madrid Protocol and the International Convention for the Prevention of Pollution from Ships (MARPOL), which accords Antarctic waters the highest level of protection, Australia and other Antarctic Treaty parties require their Antarctic shipping to meet stringent standards. All ships chartered by the AAD have strengthened hulls to provide added protection against potential oil and fuel spills, and operate on light diesel fuels.
Annex IV of the Madrid Protocol and MARPOL provide protection to the marine environment from the effects of ship operations, including:
- bilge water, oil, and oily mixtures
- waste storage, treatment and discharge
- sewage storage and treatment
- exhaust emissions.
The AAD is researching the amount and nature of debris on Macquarie and Heard Islands to determine its harmful effects and how best to limit them.
As a requirement of Antarctic Treaty Resolution I/1997, Australia has developed an oil spill contingency plan for each of its permanent Antarctic and subantarctic stations, and also requires its chartered ships to have a current contingency plan. Plans conform to the guidelines established by the Council of Managers of National Antarctic Programs (COMNAP). All expeditioners undergo basic training in fuel management, with specialist training provided for those handling major fuel transfers.
Antarctic Treaty Parties are working with the International Maritime Organisation to develop a comprehensive set of guidelines for Antarctic shipping, which are intended to protect human safety, the environment and shipping.
Further information on marine environment protection is available from the Australian Maritime Safety Authority.