ROCK OF AGES with Murrumbidgee Field Naturalists

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Lake Cowal - Wedge-tailed Eagle Kathy TenisonLake Cowal Rock - Rowena Whiting Mal Carnegie is a rock: a tall, tough country boy born and bred in this same unforgiving land which hosts the Evolution gold mine, the epicenter of our outing on November 24, 2018. He is also the rock upon which the success of the Lake Cowal Conservation Centre is assured, which has its home adjacent to the gold mine.

It was in their spacious tearoom/conference centre that Mal welcomed us with a mandatory video on mine safety. Apparently, with the stringent obligations of OH&S attached to Australian mines, too much safety is never enough. And this colossal enterprise is, happily, Aussie owned and operated.

Our host then gave us an informative talk on the mine and its history; along with lots of operational facts and figures. This is indeed a major industrial complex just 40 or so kilometres north of sleepy West Wyalong.

Then he escorted us on a tour of the mine; hard hats, hi-vis vests and safety glasses for all. We looked, for all the world, like a party of desperate politicians canvassing for regional votes!

Ah, nature at last. At the lookout above the yawning abyss of the pit we saw not one but three raptors; a Wedge-tailed Eagle, a Whistling Kite and a Kestrel. Each was effortlessly soaring above a landscape unblessed by any other living thing. So why were they there?

An open cut mine of this scale completely transforms the topography; from a formally featureless plain there now rises small mountains of rubble and ore, with the pit itself a 1.3 kilometre-wide grand canyon with near vertical sides. So the wind movement in the vicinity is itself transformed, with eddies and updrafts providing a plenitude of opportunities for the aerobatics of these joyful birds. In short, they were not seeking prey, they were just having fun!

The nominal reason for the trip was, however, to visit the small inland sea that is Lake Cowal. When full, as it was in 2016, it is said to be one of the largest bodies of fresh water in NSW, being some 18 kilometres long north to south, and 10km wide.

Alas, as it is a uniformly shallow lake – at best 3 metres deep – Mal predicts that it will be dry by February 2019: unless of course it receives a heavy inflow before then.

From another lookout we could gaze over a large part of the lake, a vista including fringing River Red Gum forests, mud flats for waders, and wide, grassy verges for grazing animals, such as the scattered emus present on that sunny, windy morn.

We also saw patches of lignum, an extraordinary plant that can live equally in and out of water, its long, thick, slender branches storing moisture much like a giant succulent.

Mal then told us a sorry tale of how, where we could now see only bare mud flats, not so long ago these were blanketed in a life-sustaining lignum “forest”. That is until some unconscionably careless campers permitted their fire to escape, totally incinerating around 1800 hectares of this precious floral resource.

“But it will grow back again … surely?” one of our number asked.

“Maybe in about 200 years.” Mal replied grimly.

Apart from the plant community itself, think what vital habitat was destroyed for so much wildlife, like the Sacred Ibis and White-winged Fairy Wren.

Our sombre mood was lifted as we were bussed back to the LCCC for morning tea (we MFNs love our food stops). Then off again to interface with the lake itself. And what splendour there was, with thousands of water birds along the shore line visible to us. The three scopes were never idle!

“All this in less than a kilometre;” Max mused “imagine how much bird life the entire circumference (my estimate, north of 60 kilometres) of the lake supports.”

I leave it to others to supply the species list; but among my favourite sightings was a family of Pink-eared Ducks foraging at the water’s edge. These were in company with several Red-necked Avocets and Black-winged Stilts. For trivia buffs: as a ratio, the Avocet has the longest legs to body size of any bird on earth!

Above these was the constant presence of Whiskered Terns, their scything dihedral flight challenged only by the arrow-like speed of a small flock of Sharp-tailed Sandpipers. Bird watching at its best!

Then back to the Centre for lunch; and another talk by our tireless host. Here he amused the “class” by producing a cannonball of hardened carbon steel. These are employed in the ore-crushing process. At first this dead weight was handed around person-to-person – until it was agreed that rolling it around randomly on the floor between the 10-pin chair and human legs was the preferred option.

Before entering the bus for our last short excursion, I experienced one of my trip highlights. This was a rock. It rested innocuously beside the path to the carpark, having been hauled in from who-knows-where; obviously to reinforce the geologic credentials of the mine.

It was about the size of a flattened Mini Minor, of sedimentary origin and of pale, warm-toned hues. As a chunk of an ancient sea bed, it contained thousands of marine fossils in unknowable laminates. All these ancient animals were seemingly invertebrate – that is, they lived prior to the Devonian (“Age of Fishes”). Among these was a seafood basket of crustaceans, and mollusks, such as chitons, limpets, periwinkles, turban shells, whelks - and small, long-extinct ammonites. There was even a sampling of echinoderms, like crinoids and urchins.

This bounty ranged from tiny to quite large, one beauty, which may have been a coelenterate, like a jellyfish or coral, being about 10 centimetres in diameter. 

Not only was there a matchless plethora of long-passed animals, some of the imprints were jewel-like in their perfection, with every pattern and texture of “skin” and exoskeleton being as hi-definition and contoured as if it were laid down yesterday – after hundreds of millions of years!

After a short drive out to see Mal’s old abandoned family homestead, we set off on our return journey; our generous and competent driver Jude at the wheel. At this point there could hardly be anything new.

“Look, Cockatiels.” said Nella, sans any special emphasis. But to me it was special indeed, as I had never seen these exquisite avians in the wild. And here they were, a small flock of seven or so, a feathered farewell winging along parallel to the bus.

Now, that’s the way to conclude yet another wonderful outing with the Murrumbidgee Field Naturalists.

Alan Whitehead

 

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