The river that knew

Mist and sky above Mooney Mooney Creek better

Looking upriver from the junction with Floods Creek

If I want a quiet morning on the Hawkesbury, my best bet is a paddle up Mooney Mooney Creek.  It’s a jet ski free zone, and that’s a very fine thing. In maybe ten jaunts on various reaches of Mooney Mooney, I’ve seen a handful of kayaks, a few fishermen and one very slow moving yacht.  Unlike Cowan Creek or Patonga, there’s no sandy beaches for frisking about on, and the oysterfarms can be navigational hazard at low tide. But if you prefer hanging out with eagles and herons to spending time with humans in charge of powerboats, Mooney Mooney Creek’s the go.

Azure kingfisher profile crop

An uncharacteristically still azure kingfisher

There are really three Mooney Mooneys, for my purposes anyway.  There’s the upper reaches, a pleasant morning’s paddle if you throw in tranquil tributary Flood Creek, lined with casuarinas and decorated with the blue and green streaks of kingfishers hunting (more on the scenes and ecosystems there in a future post).  The put-in for that trip is where the switchbacking Pacific Highway crosses the river, though if you paddle upstream you pass under the highest bridge in Australia, a symphony in soaring concrete.

Or you can go downstream, towards Lemon Tree Bay and maybe on a low-ish tide, see, on every bend and mudflat herons feasting, and if you’re lucky, spot a wedge-tailed eagle soaring overhead.

Herons in parallel back in focus

White faced herons hunting at low tide

Up there in the headwaters, you’ll often see other kayakers – there are sometimes guided tours to the area – and occasionally people camping, rather naughtily, by the side of the river.  The Great North Walk, that links Sydney and Newcastle, via most of the lovely places along the way including Berowra (of course), flanks the upper reaches of the river and once or twice I’ve heard voices of hikers walking along the track or crossing the suspension bridge that spans the top of Piles Creek.

Snake island backlit 3

Snake Island and Brisbane Water National Park

But I’d prefer to be paddling than driving and I’m a little bit lazy, so I usually put in my boat in closer to home, at Deerubbin, where the freeway crosses the Hawkesbury.  From there I paddle under the freeway and past Spectacle Island, stopping off to check out the Mooney Mooney spoonbill colony, and then upstream.  Once you get past Snake Island and Sailor’s Chest Point, there’s not much sign of human activity, apart from oyster poles.

But there’s plenty going on, even without too many of us humans around.  Last week’s outing was particularly rich in feathery encounters.  A masked lapwing family enjoying a day out by the water by the Mooney Mooney public wharf.

Comedy silver gulls ducking for crabs in the shallows near Spectacle Island.

Silver gull with crab square amend

A sacred kingfisher  in the morning sun near her burrow in an abandoned arborial termite nest.  She got so bored with me clicking away she had a nap.

A striated heron, one of the river side regulars, pretending to be a particularly striking bit of sandstone.

And further up the creek, the predictable but still wonderful sight of a pair of young sea eagles perched amongst the mangroves in the shallow waters of Fox Bay.

The young ones seem to be easier to get close to.  A bit curious and a bit clueless, perhaps, about strange legless creatures that float downstream with the tide.

Even in the peace and quiet, there’s a feeling that all the inhabitants of Mooney Mooney Creek know about us.  They know we’re there – mostly out of sight, maybe, but not entirely out of mind.  The freeway passes just behind the ridge much of the way up the valley. You see it as you pass Snake Island, the trucks and cars  appear briefly, lifted above the rocky escarpment.  Sometimes, further up the creek,  the wind shifts and you can hear the sound of the traffic.

I recently found out that the freeway’s original route went right through my tranquil paddling territory – along Pile Creek, to cross the river south of where the Pacific Highway runs.  Right through kingfisher country.

But someone in the National Parks and Wildlife Service in the late 60s or 70s stood up to the road builders and just said “No”.  No, you can’t build a bloody great big road right through the (then recently established) Brisbane Water National Park.  We’re not having it.  In the words of the surprisingly fascinating “OzRoads” website

This new route had a more expensive bridge and steeper grades than the preferred route but there was nothing the DMR could do about it.

And it’s not often you hear freeway builders say that.  I’d love to  know the full story of who in Parks fought the good fight with the Roads folk.  Everytime I paddle up Mooney Mooney Creek now, I’ll be thinking about them and saying a little thank you.

Sea eagle facing away profile crop

Other paddles from Deerubbin Reserve

Up the Hawkesbury to Bar Island

For the ambitious, further in the same direction to Marramarra Creek

Into the heart of Muogamarra National Park up the winding Kimmerikong Creek

Downriver under the gorgeous if structurally challenged Hawkesbury River Bridge

 

Further references

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

 

 

The shortest days and how to use them

The chickens let us know when midwinter’s come.  The fortnight after the winter solstice, no matter how bloody cold it is, the girls start serious egg-laying.  So even as you’re trying desperately to stash four different kinds of hot lemon pickle and a hundredweight of lemon marmalade, as you open the fridge, a dozen eggs roll out.

Lemon preserves cool closeup skinny

I went AWOL from the blog for the last six months, as the observant amongst you might have noticed.  The days just got shorter and shorter.  My garden kept growing and the Hawkesbury streamed uninterrupted to the sea, but time to write about these things just seemed impossible to find.  But now the days are lengthening (and I’ve finished my night classes), all that is going to change!

Eagle flyby long crop

White bellied sea eagle doing a fly-by of Gunyah Beach

The shortest day may have passed but it’s still pretty nippy at 5.30 in the morning when I get out of my lovely warm bed and drive off through the nautical twilight to put my kayak in the water.  When it’s 3 degrees and you have wet feet, the exact moment when the sun touches your frozen toes comes to be of critical importance.

I have a nifty little app on my phone, SunCalc, that shows just where the sun will appear over the horizon on any day of the year.  So I check the tide, and the wind, and then, on a winter morning, figure out where I’ll catch the very first light.  Putting in at Brooklyn and heading for open water is not a bad choice.

I’ve had some lovely paddles from Parsley Bay in the last year.  Quiet jaunts into Porto Bay, a shallow backwater frequented mostly by raptors and oyster fishermen…

Juv sea eagle long

Juvenile white bellied sea eagle

And, on a day with hardly any wind, I braved it across to West Head, stopping off at four beaches – Gunyah on the way and Eleanor on the way back; and on the other side of Cowan Creek, Little Pittwater with its tumbling stream and littoral rainforest and Hungry Beach and its a pair of sunbaking sea eagles.

Terns in front of Lion Island cropped closer small

Terns fishing off Gunyah Beach

I was almost bold enough that time to cross the invisible line – “limit of flatwater sailing” – that passes between Juno Point and Flint and Steel Beach, but bottled it in the end, just peeking round the corner towards Pittwater and the open Pacific beyond.

Clouds over the sea long and skinny

And last weekend, coldest it’s been on a Sydney morning in a couple of decades, I set out for Refuge Bay, where the pleasure craft rocked quietly, their skippers sleeping.  But not the kids, slipping away in their dinghies to fish and play under the waterfall on the beach.

And on journey there, what magic scenes!  The open waters of Broken Bay skimmed, concealed, curtained, framed, illuminated, by the fog.

Fishing boat and lion island

Fishermen and Lion Island

If there’s something to be said for the shortest days, it’s the long nights.  You can almost have a sleep-in and still get up before dawn.

Juno head mist dark sky

A bridge fetishist paddles to Brooklyn

I have a weakness for bridges.  Romantic trysts just happen to be arranged with the backdrop of the world’s first iron bridge.  Multiple crossings of the gorgeous Severn Suspension Bridge are absolutely essential for that work trip.  And in pride of place of the mantlepiece, of course, is a railway poster of the famous cantilever bridge over the Firth of Forth.

So perhaps it’s not surprising that my paddles lately all seem to end up under what it pleases me to call Brooklyn Bridge.  That’s not its real name, mind, but since it starts  on Long Island and takes you through the thriving metropolis of Brooklyn (population 744) I think I can get away with it.

Brooklyn bridge and stone pillars plus boat.jpg

There was that morning jaunt from Parsley Bay, past the oyster leases and beneath the swooping welcome swallows, to the top of Mullet Creek, where the Newcastle trains disappear into the Woy Woy tunnel, once the longest tunnel in the southern hemisphere.

I’ve been lucky enough to go on on some beautiful railway journeys in my life – from Montreal to New York in winter, past above-ground swimming pools frozen like giants’ ice-cubes; from southern Thailand to Bangkok, looking out at the richest of tropical orchards woven into the jungle; between snowcapped mountains and sea on the West Highland line to Hogwarts Mallaig.  But I reckon this journey along Mullet Creek, not a place that will ever be immortalised in the baby names of the rich and famous, is my favourite.  There’s something about a railway line that leaves roads far behind, forging its own way along the empty shore.

Sunrise at Brooklyn

If you ask the driver, you can get off near the top of the creek at Wondabyne, the only station sans road access in Australia.  Every now and then, you see people jumping off the train and straight into a tinnie, zooming off to the shacks on the other side of the river before their fish supper gets cold.

For a few years in the late nineteenth century, while the first Hawkesbury River bridge was being built, if you were travelling north by train from Sydney, you would disembark at Long Island, board the double-decker paddleboat the General Gordon, and steam off to Mullet Creek Station, then just north of Wondabyne.  Now people hop off here to do part of the Great North Walk – a 250 kilometre walk from central Sydney to the beautiful beaches of Newcastle – or to wander up to Pindar Cave.  Judging from the smorgasborg of rusted out craft I saw in the shallow water at the top of the creek, it’s also a place where people take their boats to die.

Then there was this weekend’s jaunt, downriver from Deerubbin Reserve – a popular spot, right by the freeway, to fish or have a picnic for those who find the perpetual roar of traffic reassuring.  With the ever present possibility of a quick exit, I guess it’s ideal for the heavily pregnant or those who find their relatives a bit hard to take.  But I can’t really bag people for their passion for the internal combustion engine since I get all hot and bothered at the prospect of a paddle underneath (count ’em) three great big bridges.

This weekend’s jaunt took me past Spectacle Island Nature Reserve, under the Hawkesbury River Railway Bridge, natch, and around Dangar Island, swished along smartly by the current and the falling tide.

Have you ever been bored enough in an airport to try walking  the wrong way up a moving footpath?  Trying to paddle across the current to get to one of the beaches on the eastern side of the island was a bit like that.  It all seemed a bit too hard in the end, so I went where the river wanted to take me, downstream, floating just above perilous rocky reefs by off Bradley’s Beach and veering round the seagrass beds.

And then through the sailing boats, swaying and tinkling like expensive marine windchimes, to Sandy Bay, the best place in the world to be homeless.  The folks whose setup I saw there – a tarp flanked by a beached ramshackle boat and a solar panel – had no-one for neighbours but a horde of blue soldier crabs.  There was no sign of the human residents, but I now know what it’s like to be a celebrity, thousands of beady eyes watching and waiting on your every move.

Quite a few people live rough around Brooklyn.  “Good caves, a shower at Brooklyn Baths and walking distance to the bottle shop”, as RB commented with unseemly enthusiasm.  In the Depression, apparently, lots of people came to live in these parts for just this reason – shelter and a bit of space for chooks or a veggie garden.  I didn’t see a chicken run in Sandy Bay but Brooklyn does seem to have some kind of common flock, judging from these good looking fellas that we met down by the marina a while back.

I reckon the Hawkesbury estuary is Sydney Harbour through the looking glass – a parallel flooded river valley, bordered by bush instead of multimillion dollar apartments.  If the Harbour has its iconic Bridge, the Hawkesbury has its own engineering marvel – nearly three times as long, resting 50 metres and more deep in soft black mud.

The modern bridge is the second one to cross the river here.  The old bridge, finished in 1887, was the last link in the railway that spanned four colonies, connecting Queensland to South Australia.

Sir Henry Parkes, on the day of the bridge’s official opening, pronounced: “In this great system of material arteries which we completed today, we see the crimson fluid of kinship coursing through all the iron veins” (Sharp, 2001, 4).  Apparently the other grandees were a bit more underwhelmed by the prospect of a federated Australia, bound together with railways.  Nonetheless, the day after, the headline in the Sydney Morning Herald was headline was “United Australia”

Bridge silhouette 1

At the time it was built, the old bridge was the longest in Australia and had the deepest footings in the world – 180 feet below the high water line – though they still didn’t reach solid ground.

The Union Bridge Company from New Jersey won the contract to build it (on a pin-jointed truss system, as I’m sure you want to know), giving Brooklyn, the railway town that was set up to house the workers, its American name.  The tender being won by an American company was one in the eye for the old country, though it pleases me in some strange way that the riveted steel for the spans was made by Arrol Brothers in Glasgow, who also worked on the bridge across the Firth of Forth.

But the original Hawkesbury River Railway Bridge didn’t last.  Its piers, filled with rubble instead of solid concrete, fractured under the weight of the trains that crossed here, the only  bit of duplicate track on the line.  The piles were starting to crack in the 30s, but the problem only came to light when a US railway geek doing a bit of light recreational reading of an engineering textbook spotted that the piles weren’t built to the original specifications.  The death knell of the old bridge, though, was the extra rail traffic of the war.

The piers of the old bridge remain, like golden castles guarding the river.

Castles 2

The footings of the 1887 Hawkesbury River Railway Bridge.  Or castles as I like to call them.

I’ve had a great time reading the fantastically detailed history of the building of the new bridge by Major-General Albert Cecil Fewtrell, the Chief Civil Engineer of the NSW railways, who supervised its completion.

There’s some entertaining reading between the lines.  When it came to putting the metal spans onto the concrete footing, it seems some fool had a plan to float the 1,600 tonne metal spans over to the pilings at water level and then haul them out with giant cranes perched on the piers.  But Major-General Fewtrell soon sorted them out:

“Consideration had been given early to the proposal to float out the spans at low level … The decision [was made] to revert to the high level method of floatation following the return of the Author from active service in 1943” (Fewtrell, 1946, 27)

The prep they did for the task of floating the massive spans from the construction docks – the cuttings still visible on the north shore of Long Island – onto the concrete pilings at high tide also gives you a sense of the guy.

A large board, representing the land and water at the site of the new bridge, was laid down in the southern tunnel. Model piers were accurately fixed in position in the “stream,” and miniature spans, pontoons, and equipment were used so that the men could practice in detail movements and prepare for emergencies.

Don’t you want to play with those 1/32 scale tiny cranes and miniature pilings?  I really really do.

Fewtrell thought that everything had gone swimmingly.  But the new bridge, the bridge that was supposed to last 200 years, is crumbling.  After years of delays, just this last week, work started on repairing the concrete footings and its rusting reinforcing steel. When I paddled past, there were huddled men in high vis jackets and mysterious icons dangling from the bridge deck – all the signs that a new engineering miracle is about to begin.  And I’m sure it’ll happen.

But at this stage, once again, I reckon it’s Hawkesbury River 1: human engineering 0.

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

Nine herons hunting

Nine herons hunting… could it be the beginning of a carol for Christmas-in-July?  Not a bad sound track, perhaps, for a paddle on a wintry 25th down Mooney Mooney Creek.

There were (roundabout) eight cormorants, some of them cacking….

… three posing pelicans

… two eagles soaring

And a kingfisher in a mangrove tree (no photo, naturally).

But realistically, I could only get all the way through the twelve days of anti-Christmas by including the many invisible mud-loving animals that all those herons were stalking.  And I’m not quite sure if I have the alliterative and euphonious verbs to use for them.  Twelve isopods…. idling? Eleven worms a-wobbling? Ten crustaceans crawling?

Even if it can’t offer swans a-swimming or geese a-laying, Mooney Mooney does pretty well for both visible and invisible animals, considering how damn noisy it is.

I first started dreaming about paddling this creek as we swooped above it, across the lofty freeway bridge.  It’s a gorgeous structure, if you are partial to well-formed concrete: elegantly curved, arching vertiginously above the treetops of Brisbane Water National Park.  An endless stream of cars and semis cross the valley on the F1, the main route north from Sydney, on the tallest road bridge in Australia, the still water 75 metres below.

The Pacific Highway, looping its way down to its own modest crossing point, has plenty of traffic too: bikers switchbacking their way up the old road. This Saturday, I didn’t see a soul in three hours on the river, but for a mile or more I could hear the hiss of compression brakes and the revving of engines.

And yet, if I had to pick a place, of all the waterways I’ve paddled so far, to find and fail to take a picture of a kingfisher, this rowdy river is the one I’d choose.  The traffic noise seems to keep the humans at bay, but not the herons.  What’s going on with the wildlife around here?

There’s plenty of evidence that traffic noise bothers birds.  I particularly like a recent experiment where researchers planted speakers in a long line to create a phantom road.  That’s just what the freeway feels like from Mooney Mooney Creek – a road you can hear all over but mostly can’t quite see.  The phantom road, with its invisible traffic masking mating and alarm calls and the sound of approaching predators, cut numbers by a quarter, and drove two species away from the area entirely.

Some cope better than others.  High pitched songs are less likely to be blocked out by the roar of traffic, and so squeaky voiced birds are more likely to hang around in noisy places.  Species with a little vocal versatility often start to sing a bit higher, a little slower or in purer tones, just to be heard.

If you’re carnivorous, being able to hear the critters scuttling around in the bushes is a boon. Seeds and nectar are less likely to make a break for it, so background noise seems to be less of a big deal for the plant-eaters.  Also, birds that feed on the ground seem to mind the noise less – perhaps there’s more obstacles between them and the din.

Everyone agrees that in loud places, birds spend more time on the alert for predators – a high maintenance lifestyle.  That said, some nest-robbers are also put off by the rumble of traffic, so for some species, chicks hatching in noisy nests have a better chance of survival.  If you can handle the decibels, you may have a competitive advantage.

What does all this tell me about the plentiful birdlife of Mooney Mooney Creek?  Thinking about it, I saw high-pitched squeakers, mud-hugging stalkers and sharp-eyed hunters (see, I’m getting into the swing of this avian carol singing thing!)  I’m guessing striated herons don’t echolocate for crabs.  This white-faced pair were happy to ignore not just the distant thunder of trucks but the much more immediate annoyance of a nosy canoeist with a camera.

“The mud is like a Christmas tree”, my eight year old said, hearing the story of my low-tide adventures, “and the bird were excited to find all their presents”.

When the eating is this good, it seems, the soundtrack scarcely matters.

References

Francis, C.D. (2015) “Vocal traits and diet explain avian sensitivity to anthropogenic noise” Global Change Biology 21(5), 1809-1820

Francis, CD and Jesse R Barber (2013). A framework for understanding noise impacts on wildlife: an urgent conservation priority. Frontiers in Ecology and the Environment 11: 305–313. http://dx.doi.org/10.1890/120183

Francis, CD, Ortega, C and Cruz, A. (2009) “Noise Pollution changes avian communities and species interactions” (2009) Current Biology 19(16) pp.1415-19

Patricelli, Gail L. and Jessica L. Blickley (2006) “Avian communication in urban noise: causes and consequences of vocal adjustment” from The Auk 123(3): 639-49