Tag Archives: New South Wales

Ancient Australian fish discovery

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Reconstruction of Edenopteron, photo Melissa Adams

From the Australian National University:

Ancient fish species discovered

FRIDAY, 08 MARCH 2013

Researchers from The Australian National University (ANU) working on the New South Wales south coast have discovered a new species of ancient fish, after unearthing the largest fossilised lobe-finned fish skull ever found in rocks of Devonian age. The descendants of these ancient fish evolved into the first land animals.

Dr Gavin Young from the Research School of Earth Sciences and his research team were excavating the skeleton of an extinct armoured fish from 360 million-year-old rock near Eden, NSW, when the bones they uncovered suggested there was more in the site than met the eye.

“As we lifted out the block, we noticed a very large fang, at least 4 cm long,” said Dr Young. “Armoured fish don’t have teeth, so we knew there must be a much larger predator also preserved at the site.

“We uncovered an almost complete skull and shoulder girdle of an enormous lobe-finned fish, with jaws about 48 cm long.”

Preparing the fossil in the ANU laboratory took several years.

“We used traditional methods of acid etching and casting, but also experimented with the latest surface scanning techniques to reconstruct the bones, and used the ANU high resolution CT scanner to investigate the internal structure of the teeth.

“We compared the shape and structure of the preserved bones with about 100 fossil fish species from elsewhere in the world. It turns out that we have not only found a species new to science, but also a new genus of lobe-finned fish, which we have named Edenopteron after the town of Eden,” said Dr Young.

The species name Edenopteron keithcrooki acknowledges Professor Keith Crook of the former ANU Geology Department, who supervised student geological mapping on the NSW south coast over several decades, when many of the important fossil fish sites were discovered. The new species is described today in the international journal PLOS ONE.

The discovery of this new species has implications for the classification of other Devonian lobe-finned fish, says Dr Young.

“This animal had some unusual features compared to Devonian fish fossils from the Northern Hemisphere, including extra bones in its palate, and strange ornamentation on the scales,” said Dr Young.

“These features were first identified in fish fossils from the well-known Canowindra fossil site in central NSW, and we have now found the strange scales at the Jemalong Range near Forbes, and in similar-aged rocks in Australian Antarctic Territory. The Eden site is only the fourth place in the world where Devonian fish show these unusual features,” explained Dr Young.

When Edenopteron was alive, Australia and Antarctica were joined in the great southern supercontinent of Gondwana.

“It’s pretty clear that we had an endemic lobe-finned fish group in this part of the world, and that has very interesting consequences for hypotheses of where the first land animals evolved,” said Dr Young.

The next step for the research team is to continue excavating the site to see if the body of Edenopteron might be preserved deeper in the rock.

“That would be a massive excavation because it would be 2 to 3m long, but would most definitely be an absolutely spectacular find,” said Dr Young.

This work was completed under an ARC Discovery Grant. The article can be accessed here.

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Help Australia’s regent parrots

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This is a regent parrot video.

From Australian Geographic:

Eagle-eyes needed to spot rare regent parrots

THE REGENT PARROT – sometimes called the ‘rock pebbler,’ ‘black-tailed parakeet’ or ‘smoker’ – is well-known for being a bit of a chatterbox. But the bright-yellow and olive-green birds, local to Victoria, New South Wales and South Australia, are becoming known for something far more concerning – their declining population.

Help is on the way, though, in the form of a national recovery plan recently launched by the Victorian Department of Sustainability and Environment (DSE).

Victor Hurley, DSE biodiversity officer and co-author of the plan, estimates there are 1500 breeding pairs in the wild, but says one of their first priorities is to find out just how many regent parrots are out there. “We are interested in knowing of any new breeding colonies,” he says.

The call is out for bird spotters

Victorians are being called on to report sightings of the parrots’ breeding locations, commonly found inside deep hollows in river red gum trees along the Murray, Wakool and Wimmera Rivers.

The recovery plan also addresses threats to the regent parrot’s habitat and encourages people to take precautions if they are near breeding sites.

Steps include limiting boat and 4WD activity near where the birds are breeding, reporting any illegal trapping or shooting and containing camp-fires.

“Fires along the river bends can cause huge problems when people are inattentive to their camp fires, which can and end up taking out sections of the forest with hollow bearing trees,” Victor says.

Parrots hole-up away from danger

In springtime, regent parrots nest inside hollows up to 2m long with small entrances roughly 9cm wide. The unusual shape of these hollows is perfect for guarding against goannas and parasites that live around the water.

Males are often spotted flying into their hollows after long journeys to collect seed, but it’s the parrots’ excitable calls that will let you know they’re around, Victor says. “Most often you can hear them before they fly into view.”

The DSE hopes the recovery plan will ultimately reverse the parrot’s population decline.

The plan has been adopted by the parrots three home states and is registered under the federal Environment Protection of Biodiversity Act.

If you’ve spotted one of the regent parrot’s breeding sites, call the DSE Mildura office on 03 5051 4500.

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