Thursday, August 11, 2005
Australian volcano blows its top!
The volcanic activity is changing the shape of the island and ultimately changing the environmental make-up of its cold and windswept surface.
Environment Minister Ian Campbell said satellite images had detected the volcanic activity on the rarely visited island, 4,100km southwest of Western Australia.
McDonald is better known for its surrounding waters which are home to the Patagonian toothfish, heavily poached by ships transgressing Australian waters.
Its steep shores, surrounded by treacherous seas, were last visited by humans in 2002.
Senator Campbell said the McDonald Island volcano had been dormant for 75,000 years before erupting for the first time in 1992.
He said there had been several eruptions since - most recently in 2001 - and the island's size had doubled in that time from 1.13sq km to 2.45sq km.
"The McDonald Island volcano is also unusual because, unlike most oceanic volcanoes, it sits on a shallow submarine plateau," Senator Campbell said.
"(This) means its eruptions are not as wild and fiery as some, instead producing a slow-moving mass of lava that seeps and spreads.
"Despite the slow-moving nature of the lava, eruptions over the past 13 years have caused startling changes to the island's geography, obliterating some landmarks and creating new ones."
Senator Campbell said the island was previously inhabited by macaroni penguins.
"Now, because you've created this pumice that comes out of the volcano, you've created this very big beach area with pumice, which is one of the desirable habitats for rookeries for the king penguin.
"King penguins, which hadn't been seen on this island for ever, I think, or a long time, have actually started colonising the island.
"You're getting this increase in biodiversity occurring.
The island is within the Heard Island and McDonald Islands (HIMI) Marine Reserve, one of the world's biggest marine reserves.
It is just 44km from Australia's only other active volcano on Heard Island, where there has not been any activity for some time.