Off Australia’s south-eastern coastlines, three great oceans merge to create a super-abundant and unique marine environment. A huge upwelling of deep nutrient-rich water is created when the warm currents of the Pacific and Indian Oceans combine with the cold Southern Ocean.
The ocean springs to life, phytoplankton bloom and there is an explosion of krill. This generates a feast amongst seabirds, seals, dolphins and whales.
The south-east marine region is globally recognised for its high level of endemic species - found nowhere else on earth. In fact around 85% of the known fish and 62% of the seafloor flora are considered endemic.
Amazing deep ocean canyons are found here, providing habitat for a diverse range of species, from ancient deep water corals and sponges, to fish and crabs with bizarre adaptations for survival in the deep. Superb seamounts off Tasmania can rise as high as 4,000 metres! These restrict and intensify deep ocean currents, creating a perfect environment for corals and other bottom-dwelling species.
Much of the marine life here is found nowhere else. If we lose them from the south-east, they are gone from the planet forever.
Photo: CSIRO
Rapidly warming waters, combined with heavy commercial fishing pressure and impacts from oil and gas industry activities, has created a perfect storm of decline.
The waters in the south-east are heating at a rate 3-4 times the global average making it a global warming hotspot. Southern reef species are struggling; the population of common sea dragon (Phyllopteryx taeniolatus), for example, has declined by 57% over the past decade. In other parts of the country species may be able to migrate south in response to warming, but off southern Tasmania species are blocked by the deep Southern Ocean barrier.
The oil and gas industry threatens marine life through seismic testing, drilling, risks of spills and accidents, and building and decommissioning infrastructure, and via the climate impacts of burning the fossil fuel.
Heavy commercial fishing is adding to this pressure and fish populations are now in big trouble. No Australian commercial fishery has put as many species on the endangered list as the south-east’s Commonwealth-managed fishery and in 2021, 29 out of 43 fish stocks were declining. CSIRO climate projections predict a 40% decline in the next 20 years for some of the major targets of commercial fishing.
Source: CSIRO, 2021, Regional Projection for Southern AustraliaThe network extends from the warm temperate waters around South Australia, Victoria and New South Wales, to the cool temperate waters around Tasmania. This network of Commonwealth marine parks comprises 13 marine parks, covering more than 226,000 km2.
Established in 2007, the marine park network is well overdue for renewal. Our understanding of the incredible values and growing threats to the region have changed markedly. We now know the marine park network falls well short of what is needed to safeguard marine life and their habitats from decline and extinction: The South-east marine park region currently has the poorest marine park protection in the country, with 92% of the region currently without marine sanctuary protection.
To protect its outstanding marine life, experts advise we must more than double the area protected in marine sanctuaries. These protections will help safeguard our threatened seabirds, dolphins and whales. Expanding marine sanctuaries will be essential to safeguard ocean ecosystems and marine life, including stocks of commercially and recreationally important fish species, through a period of great change.
The Government is currently reviewing and updating the South-east marine park network. Stay tuned as we will need your support to ensure that strong protections for our special south-east get across the line.