Save Our Marine Life: our unique south-west seas

In late February 2009, a new collaboration of key Australian and international conservation groups, including the Wilderness Society, launched Save Our Marine Life to secure the future of Australia’s south west marine environment, by creating large marine sanctuaries.

Up to 9 out of 10 marine species found off Australia’s south west coast are found nowhere else on Earth, but less than 1% of this region is protected. This globally significant region is home to a far greater proportion of unique marine life than the Great Barrier Reef.

A male Weedy Sea Dragon, photo: Jenita Enevoldsen

Another world beneath the waves

The azure blue waters from Kalbarri to Eucla, fed by the south flowing Leeuwin current, hide an extraordinary world of underwater mountains and gorges, where unique species flourish.

Australia’s largest underwater canyon, the Perth Canyon, lies just beyond Rottnest Island. It is as wide as the Grand Canyon and much deeper. It is the ancient bed of the Swan River and it meanders from the edge of the Rottnest Shelf for 100 km to meet the ‘abyssal plain’ (the deep ocean basin floor) at a depth of 4000m.

The Perth Canyon is one of only two feeding grounds for blue whales known in Australia. Thus, it is essential to the survival and recovery of this critically endangered species - the largest animal on earth.

Further south, the Naturaliste Plateau is the deepest marine plateau off the Australian continent and ranges from 2000 to 5000m deep. Around 90,000 km2 in area, this entire plateau is now in Australia’s care.

The Albany Canyons includes 32 canyons spread along 700 km of the continental slope from Albany to east of Esperance. Further offshore lies Australia’s highest underwater mountain range - 100,000 km2 of rugged seabed called the Diamantina Fracture Zone. At around 7300 m deep, it is also the deepest point in Australia’s oceans . Yet, we know little about this region because our current marine technology can’t measure the deepest depths, let alone sample its seafloor.

There are numerous other features of Australia’s south west marine region which are amazing ‘hotspots’ for marine life including the Houtman-Abrolhos

It is the combination of the underwater seascape, the Leeuwin Current bringing tropical waters south and very limited runoff from land which makes our south-west waters globally high in unique marine species. Our knowledge of the extraordinary biodiversity of this region continues to grow with each new research voyage.

Support for marine protection

The Save Our Marine Life collaboration has produced a stunning report— Protecting Western Australia’s big blue backyard— documenting the values and beauty of the region.

It recommends the Federal Government create large sanctuaries to secure the future of Australia’s south marine region and identifies a series of globally significant ‘hotspots’ for marine life in the waters off Australia’s south west which must be protected. To engage with the campaign and to download Protecting Western Australia’s big blue backyard visit:
www.saveourmarinelife.org.au