The Great War and rubbish

Hole pattern abstract

There’s nothing I like better than a scene of elegant industrial decay.  Place that ruin-porn in the tranquillity of the Hawkesbury at midwinter.  What could be finer than a paddle around a rusted out wreck on a still morning, in the company of breakfasting eagles and kites?

What surprised me, back on land, when I dug around to find out more, was the age of this beautiful ruin.  The Parramatta was the very first ship commissioned for the newly formed Australian Navy after Federation.  It was built in 1910, the first of six torpedo boat destroyers to be constructed by Fairfield Shipbuilding and Engineering in Glasgow.  The destroyer was part of the Australian Fleet in the Pacific during the Great War, hunting enemy ships up the Sepik River in New Guinea, patrolling the waters around the Phillipines, Malayan and the East Indies, and  later, battling submarines in the Mediterranean and the Adriatic.

Ladder interior amended crop

The interior of the wreck of the Parramatta

It’s been a very long time since the Parramatta did what she was designed to do. She was taken off to be dismantled in 1929, when my granddad was a toddler.

But in her post-naval career, she’s certainly been reused a few times.   After being decommissioned, she was sold to the NSW Penal Department, along with her sister ship The Swan, and towed to Cowan Creek where each boat was to accommodate 50 convicts. The prisoners were supposed to work on a new road from Bobbin Head to Brooklyn that was to be “the finest marine drive in the whole world”.  The stretch from Windybanks to Bobbin Head was declared a detention area, but in the end, with a change of government and not a single vote in favour of the plan from the Kuring-gai Chase Trustees, the idea of building a road was shelved and the boats were sold again.  Their purchaser hoped (ultimately fruitlessly) to use them as a floating hotel for fishermen.  It’s rumoured they went on to house unemployed men and store water during the Depression, before being towed to the north end of Milson Island and used as a floating sand and gravel pit.

Flowing fog at Milson's Island - the location of the Parramatta is on the right

Looking north past Milson’s Island – the wreck location is near the right of the photo

In the early 1970s, the historical significance of the wreck was began to be appreciated and the bow and stern of the ship were retrieved and preserved for posterity – the stern at Queens Wharf Reserve on the Parramatta River, and the bow at the Garden Island military base in Sydney.  Other bits have been less officially repurposed – all its valuable brass portholes, for instance, have been nicked.

It’s not really clear how the wreck ended up on a mudbank on a bend of the Hawkesbury.  It’s rumoured she and her sister ship The Swan were being towed downriver in a gale in 1934 when they broke away.   The Swan filled up with water and sank twenty metres deep in the river near Little Wobby public wharf, while the Parramatta was stranded in the shallow water amongst the oyster farms below Cascade Creek.

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Looking over to Grace’s Shore in Muogamarra National Park

She’s not the only bit of flotsam and jetsam on that bend of the river, though, by a long shot.  I pulled in amongst the mangroves to stretch my legs below the waterfall, to find all manner of rubbish.  A discarded shopping bag was filled with drink bottles, polystyrene, coke cans, bait bags and the odd thong in a matter of minutes.  I even found a functional tupperware container and matching lid, some thing that I almost never see in my own kitchen cupboards.

Parramatta with hills amended

I have no pictures of any of this trash, needless to say.  Unless it’s on the epic scale of Edward Burtynsky’s sublime depictions of industrial landscapes, utterly transformed by excavation and waste, our tide of plastic detritus is nowhere near as photogenic as the rusty bones of our military past.  But it will will last hundreds, if not thousands, of years longer.

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Other local history posts

The Hawkesbury vs the engineers: some history of the Hawkesbury Railway Bridge

Canberra on Cowan Creek? The strange and beautiful story of Smith’s Creek.

The ghost freeway: the wildlife and history of Mooney Mooney creek

Two sad islands, three whistling kites: stories from Peats and Barr Island

Further references

Boon, Paul (2017) The Hawkesbury River: a social and natural history, CSIRO publishing.

Broken Bay at low ebb

Last weekend I decided to explore the lower reaches of Mooney Mooney Creek from its meeting point with the Hawkesbury, riding on a rising tide. After my spooky solo paddles in Mangrove Creek, I had a hankering for the open horizon and a bit of human life around me. From my put-in at Deerubbin Reserve beside the freeway, and all the way round Spectacle Island, a nature reserve in the mouth of the creek, the constant hum of the traffic and the echoing rumble of trains crossing Brooklyn Bridge remind you that “civilisation” isn’t far away.

Low tide at Mooney Mooney Creek means mud and oyster leases.  The lingering blue haze from last week’s hazard reduction burns descended on the poles and frames, forlorn in the shallows, blurring them into beautiful abstracts.

The story of oyster farming in the Hawkesbury in recent times is a sad one, full of strange historical ironies.

People have been harvesting shellfish from the shores of the river for a very very long time and Sydney rock oyster has been farmed in Broken Bay since the 1880s.  In those days oysters were dredged from the estuary floor and after the meat was eaten, the shells, along with those from ancient middens, were burnt to make lime for mortar.

But in 2004, after a hundred years of farming oysters here, Qx disease hit the Hawkesbury.

The “Q” in the name stands for Queensland.  The Sunshine State produces a 10th of the oyster harvest it did in the nineteenth century, thanks to Qx and to the oyster-infesting mudworm (introduced from New Zealand in the 1880s along with imports of oyster spat). The “x” was a scientific shorthand for “what the hell is this anyway?  We really don’t know”.   Since then, researchers have figured out that Qx is caused by Marteilia sydneyi, a single-celled organism that during the summer infects oysters, causing them not just to slowly starve to death, but also to reabsorb their own gonads (nasty!).  The parasite then releases spores that cycle their way through a polychaete worm, Nephtys australiensis, in the winter, before reinfecting the oysters the following season.

M. sydneyi isn’t always the kiss of death.  The parasite is found in estuaries all along the coast of NSW and Queensland, even in “low risk” areas where Sydney rock oysters are still being commercially grown. Environmental stress, it seems, triggers outbreaks of Qx and surprisingly few wild Sydney rock oysters, the ones I saw lining the rocky shores of Mooney Mooney Creek, die from Qx. Which is good, if mysterious, news.

So, facing of losses of over 90% of the harvest, what could save the oyster industry in the Hawkesbury?

It was noxious pest to the rescue.

The Pacific oyster, farmed in Japan for centuries, was smuggled into Port Stephens in the eighties and spread quickly through the intertidal zones of New South Wales.  It’s a fecund and fast growing bivalve, planktonic eggs and larvae travelling far and wide, crowding, outgrowing, and sometimes settling on and smothering native rock oysters. A “selfish shellfish”, in the words of one inspired Tasmanian subeditor.

The very qualities that have made the Pacific oyster such a hateful invader came to the rescue of the Hawkesbury farmers in 2005.  A process for producing sterile “triploid” Pacific oysters had been developed in North America in the 1980s, with the aim of pumping out meatier shellfish fast. When fertility mean spawning 40 million eggs in a season (not to mention changing sex several times over a lifetime) avoiding reproduction saves a lot of energy.

Local farmers restocked with these “triploid” Pacific oysters.  As well as being immune to Qx, they were ready to harvest in less than two years compared to the three and a half years it takes rock oysters to reach the table.  The new “tamed” Pacific oysters took the Hawkesbury by storm.

And then in 2013 disease struck again. Millions of oysters were wiped out overnight by a virus that affected Pacific oysters and Pacific oysters alone.

Like the oyster itself, the scientifically spawned sterile “triploids”, and indeed the settlers that farm them, “oyster herpes” or POMS (Pacific Oyster Mortality Syndrome), first seen in France in the late noughties, had circled the globe to Broken Bay.

Only three oyster farming businesses are still going in the Hawkesbury these days, hanging on for scant supplies of Qx resistant rock oyster spat, first found amongst the survivors of the Georges’ River outbreak in the mid 1990s.

Right now, the derelict oyster farms are mostly places for posses of pied cormorants to hang out.

But there’s still plenty of life to be found at Mooney Mooney at low water: globe trotters like the eastern curlew, exhausted after a long flight south, and locals like the rock warbler that only lives on Sydney sandstone, compensating for its drab colours and homebody ways with a goth-style nest of grass and spider webs it hangs in the darkness of caves and crevices. And I clocked a new heron record – twenty at least, catching crabs in the mud of low tide.

References

Michael C Dove, John A Nell, Stephen Mcorrie and Wayne A O’Connor “Assessment of Qx and Winter Mortality Disease Resistance of Mass Selected Sydney Rock Oysters” Journal of Shellfish Research 32(3) 681-87 doi: http://dx.doi.org/10.2983/035.032.0309

Wayne A O’Connor and Michael C Dove “The changing face of Oyster Culture in New South Wales, Australia” Journal of Shellfish Research, Vol. 28, No. 4, 803–811, 2009.

J.A. Nell “The history of oyster farming in Australia” Marine Fisheries Review 63(3), 14-25