What do you get if you cross a snake with a panda?

Darter from behind close crop shorter

The geometric art on the Australasian darter’s back

Things I learned from last weekend’s paddle from Lake Macquarie’s Shingle Splitters’ Point to Dora Creek:

1. When kayaking on the largest permanent salt water lake in the southern hemisphere, always remember fetch.  Fetch can defined as the distance of open water over which wave-creating winds blow. Where does the word “fetch” come from, I hear you ask?  From the cries of sinking kayakers as they disappear behind the white tops: “Fetch the emergency services!”

(Don’t be deceived by the apparent smoothness of the lake surface here – once the wind picked up I was too busy thinking about staying afloat to take any pictures)

Big lake

Heading across Lake Macquarie from Shingle Splitters’ Point

2. The lyrics of Kenny Rogers’ immortal song “The Gambler” don’t just apply to card sharks, but also amateur bird photographers.  “You never count your money when you’re sitting at the table.  There’ll be time enough for counting when the dealing’s done”.

Because the few seconds you spend checking to see if that wildly optimistic over-the-shoulder shot caught the hunting osprey mid-dive, will be ones in which the hungry raptor wheels around and splashes down again, right next to your boat.  And flies off before you can get the lens cap off your camera.

Osprey bum bigger long

Departing osprey

3. While adult Australasian darters are the most sinuously elegant of birds, poetry in snake-like motion, their offspring are actively disturbing.

What is it about these baby darters?  They’re very very fluffy.  Like a gorgeous soft baby panda.  A delightfully fluffy decapitated panda with the head of a snake. A sweet duo of snake-panda in a nest white-washed with guano. And they didn’t think much of me either.

In South America, they’ve found are darters in the fossil record that weighed 17 kilos – more than eight times as heavy as these not-insubstantial characters.  Just imagine how unnerving it would be in a kayak under that humungous reptilian chick when it let fly.

There’s no danger of modern darters – anhinga to give them their formal name – vanishing like their massive forebears. Like humans, darters like deep, still water not choked with vegetation, as long as there are overhanging trees to nest and perch on.  And they don’t mind introduced fish like carp and perch, so they’re doing better than birds that prefer marshy wetlands or are fussier about their diet.

A few weeks back, my brother and I watched with a fine male hunting from the shore of Lake Macquarie in the golden light of the late afternoon.  Even after the bird vanished below, we could follow its progress by the tiny fry that leapt from the water.  The sinuous head reappeared moments later, a fish impaled on its beak.  It took him a few goes, but finally he managed to flick it into the air and gulp it down.

I’ve seen plenty of snake birds, as they’re sometimes called, over the last couple of years as I’ve paddled around the lower reaches of the Hawkesbury and the rivers and lagoons along the Central Coast.  Familiarity hasn’t dulled my enthusiasm for them – the males geometric abstracts, the females russet in the sun, their elegant necks holding poses as striking and absurd as those of modern dancers.  But I’ve never seen the young ones before.

Darters breed erratically, it seems, whenever and wherever conditions are good.  They will fly long distances – up to 2000 ks in the non-breeding season – and will nest inland when floodwaters linger.  Maybe the stretch of Dora Creek where I saw them is a regular breeding spot.  In one fecund tree I saw two empty nests, along with two brim full of snake-pandas and guano.   Or perhaps the vacant real estate belonged to other waterbirds, since darters seem to like to nest in company.  Down the river, egrets, cormorants and partly-fledged juveniles were hanging out on a branch together, not far from this perturbed looking male with his runaway egg.

One way or another, the younger chicks seem to prefer intimacy to solitude, finding comfort, as they crouched in their absurdly flimsy nest, in the softness of their siblings’ breasts and the predatory encircling of each others’ snakey necks.

Three darter chicks snuggling crop tighter

Juvenile Australasian darters snuggled together in what remains of their nest

 

In praise of sewage

“Cockle Creek? Ooo, I wouldn’t put in there” my sister’s mate, the local, said “They’ve been dumping heavy metals in that spot for years! And there’s the sewage farm up the river as well.  I’d steer well clear”.

I muttered to my sister as we walked away “What do you think? Are you worried about heavy metals and sewage?”

“Nah!  Let’s do it!”

Sunrise on Lake Macquarie

Sunrise on Lake Macquarie

The power of poo.  Over the last couple of years, I’ve been hearing a lot about it from my fabulous friend and colleague, Cath Simpson, at this very minute writing a documentary for Radio National full of plops and splashes.

Thanks to some bad experiences with cholera and typhoid, we modern city dwellers generally a bit iffy about human excrement. But the bacteria that dwell in and on us – our own personal ecosystems – seem to be quite critical to human health.   While I’m a huge fan of the toilet, poo is not all bad.  If you have a nasty case of Clostridium difficile, for instance – an infection that kills 30,000 Americans every year, often older people in hospitals who have had their bacterial ecosystems depopulated by antibiotics – a “faecal transplant” from a healthy donor is might well be your best chance of a cure.

If the much of Western world, with its convenient superphosphate fertiliser and cow-pat free central heating, has been a bit “ew” about excrement, one sub-culture has held the faith.  Bird watchers have never lost confidence in the value of ordure.

Cormorant diving crop for trim

Painterly pied cormorant fishing in Lake Macquarie

When Birdlife Australia asks “where’s your favourite birdwatching spot?”, do you choose an offshore island, fringed with white sand?  the lush splendour of the tropical rainforest?  Or choice number three, a sewage treatment plant? And you guessed it, the first comment is a ringing endorsement of the glories of the Alice Springs Sewage Ponds.

So I wasn’t really surprised at the new and exciting birdlife I saw up  Cockle Creek in amongst the drowned computer monitors, abandoned bridge footings and Impressionist riverscapes subtly enhanced by a discreet discarded tyre.

So many striated herons I got bored of taking photos.  White-cheeked honeyeaters.  Orioles.  Black faced cuckoo shrikes. White breasted woodswallows, showing off their 80s batwing styling.   Double-banded finches with their neat dress shirts, black ties and cummerbunds.

Why are sewage treatment plants so great for birds?  Well, wetlands are a particularly threatened habitat – a third of Victoria’s wetlands have been drained over the last two hundred years, for instance – and old-style sewage ponds offer alternative places for birds to feed and rest, especially during droughts.  With plenty of nutrients, the settling ponds of sewage treatment plants actually offer more invertebrate snacks than natural wetlands, and sustain a greater range birds. Christopher Murray’s research in Victoria has found that newer treatment plants – the dynamic sounding “activated sludge” facilities – that take up less expensive real estate than old-fashioned waste stabilisation ponds (and smell better) are less appealing from a waterbird’s point of view.

If the news on sewage plants is pretty good, I’m not so sure about the heavy metals. Cockle Creek really has been a dumping ground for cadmium and lead, among other things, from the smelter in Boolaroo, on and off for more than a century.  There’s black slag from the plant tucked away in all sorts of unexpected places around the lake shore and lead, zinc, mercury and cadmium lurk in the creek’s sediment, 70 centimetres deep.

The smelter closed down in the noughties and the site is still being “remediated” for housing.  Previous “abatement” strategies seemed to involve scraping off a few centimetres of topsoil and (after most of the local pre-schoolers were found to have worryingly high levels of lead in their blood) urging kids to  “Wash wipe and scrape – you’ll be right mate!”. In the 1980s and early 1990s, the streets closest to the “The Sulphide” were rented out on the strict condition that the household should have no children or pets.

There’s a giant Bunnings there already, though, amidst the rubble.  Perhaps the logic is that the visiting DIYers are heading home to put a mallet through an asbestos wall, so where’s the harm in throwing in a spot of bonus lead?

The local birds seem to be doing okay, though.  A pair of ospreys nest at the top of a Norfolk pine at Speers Point, where Cockle Creek flows into Lake Macquarie, and this last year they’ve had chicks.  Osprey are locavores and since they’re at the top of the food chain, anything toxic in the fish they eat ends up in their chicks.  Eventually.  It takes a while for our endlessly updated array of contaminants – from DDT to teflon, fire retardants and hypertension medications – to make it into the bloodstream of the baby raptors.

Osprey wings bent crop wide

Osprey with fish at Speers Point, Lake Macquarie

I’ll be back to Cockle Creek for sure, to see what the local sewage has in store for me.  Trying to tread lightly, and hoping not to feel too much lead and mercury squelching between my toes…

D in canoe at dawn small more waterReferences

Murray, C. G. & Hamilton, A. J. (2010). Perspectives on wastewater treatment wetlands and waterbird conservation. Journal of Applied Ecology, 47(5), 976–985. DOI: 10.1111/j.1365-2664.2010.01853.x

Murray, C. G., Loyn, R. H., Kasel, S., Hepworth, G., Stamation, K. & Hamilton, A. J. (2012). What can a database compiled over 22 years tell us about the use of different types of wetlands by waterfowl in south-eastern Australian summers? Emu: Austral Ornithology, 112(3), 209–217. DOI: 10.1071/MU11070

Murray, C. G., Kasel, S., Szantyr, E., Barratt, R. & Hamilton, A. J. (2013). Waterbird use of different treatment stages in waste-stabilisation pond systems. Emu: Austral Ornithology. DOI: 10.1071/MU12121

Murray, C. G. & Hamilton, A. J. (2012). Sewage ponds a refuge for wetland-deprived birds. ECOS, 175. http://www.ecosmagazine.com/?paper=EC12418