Wildlife reboot: birds 2.0

Another January, and another trip to Ganguddy, on the western site of Wollemi National Park.  Same marvellous geology, same refreshing dam water, same hot weather.

But some things were different this year.  After the stupendously dry winter, the eucalypt forest was parched, the undergrowth sparse and the leptospermum flowers of last year’s visit few and far between.  We found a patch of sphagnum moss perched in a bowl of sandstone boulders so dry it crunched underfoot.

A “green” satin bowerbird panting in the heat

We spotted plenty of lizards, and the diggers were out in force – lyrebirds wandering through the camp as they tried to scratching their way down to moisture and a wombat turning up to twerk on a picnic bench.  But up in “kingfisher alley”, just before the Cudgegong River disappears into the reed beds, there were fewer blue and green flashes by the water.

Around the camp site, the bowerbirds and treecreepers panted in the heat.  Apart from the ubiquitous reed warblers, there seemed fewer birds altogether.  No sign of the friarbird teenagers of last year, and even the baby swamp hens seemed thin on the ground.

You have to wonder what it takes to change ecosystems irrevocably.  How many dry winters before the old inhabitants decide living and breeding here is just too tricky?  And who would move in to fill their place?

Back at Berowra after the trip, there are changes in the garden too… surprising ones.

We knew we’d be losing the sparrowhawks soon enough, but the family has dispersed in an unexpected orderThe adults disappeared off the scene weeks ago, and by the time we made it home with our ridiculously overloaded vehicle and small and ancient fleet of boats, the siblings had parted too.  There’s just one young’un now.  He seems lonely.

There’s a constant plaintive calling from the trees out back, that seems to intensify when he has prey on hand.  I’m not quite sure if he’s warning his imaginary sibling off or calling him to come and share a meal.

And that’s not the only shift in the soundscape around here.  The sparrowhawks have cut a swathe through the bird population on the premises.  Baby brushturkey numbers have fallen from previous plague proportions, noisy miners are few and far between and the “house” birds of yesteryear – red and little wattlebirds – are now just occasional visitors.

But as the numbers of resident raptors has dropped, a new set of critters have settled in.  Lewin’s honeyeaters which we’ve only seen once or twice in the backyard over the last seven years, have made our backyard their new home.  And we also appear to have acquired some brown thornbills, a raptor snack food if ever there was one.  And the local eastern spinebills, another tasty morsel for a sparrowhawk, are spending more time around here too.

The only explanation I have for the change of personnel is that the hawks have bumped the notoriously territorial wattlebirds, leaving the field open for new arrivals.

I’m pretty happy to have a new set of birds in the garden.  My dream scenario, I have to admit, would be to order up some songbirds that are a bit easier on the eye.  My birdwatching brother puts Lewin’s in a honeyeater “bin taxon” of pretty similar and drab looking birds it’s hardly worth distinguishing between.  Cruel, perhaps, but fairly accurate.

So, why not some new holland honeyeaters, for instance – gorgeous looking locals.  Or (still, my beating heart!) what about some pardelotes?  Just one or two?

On the other hand, it’s possible that all the vibrantly coloured small birds in the neighbourhood have been made into multicoloured meals over the past three months by our family of raptors.  After all, there’s got to be some evolutionary reason for all those SBBs*.

*note: this is a throwaway remark absolutely unsupported by any science.

 

Previous posts about Ganguddy

A bit about Ganguddy’s history and geology – and a little Tim Low on the side

Snakes versus whining teenagers – last year at Ganguddy

 

More on our sparrowhawk summer

Death and sibling rivalry

The new generation of sparrowhawks emerges from the nest…

Baby brush turkeys versus nestling sparrowhawks… the battle of the backyard baby birds

The collared sparrowhawks return to our backyard… or are they brown goshawks?

A first glimpse of the sparrowhawks… and a beautiful white goshawk visits the washing line

 

Further reading

Stephen Garnett, Donald Franklin, Glenn Ehmke, Jeremy VanDerWal, Lauren Hodgson, Chris Pavey, April Reside, Justin Welbergen, Stuart Butchart, Genevieve Perkins and Stephen Williams (2013) Climate change adaptation strategies for Australian birds: Final Report, National Climate Change Adaptation Research Facility

Office of Environment and Heritage, Premier’s Department (2011) New South Wales Climate Impact Profile Technical Report: Potential impacts of climate change on biodiversity

Death & sibling rivalry

Both birds eyes crop better again

The sibling sparrowhawks in their favourite tree… in my backyard!

It’s happened. Our babies, only three weeks or so out of the nest, are now out there in the big wide world, killing for themselves.  It brings a tear to your eye.

Distant with second bird flying crop

Keeping an eye on little brother or sister

But it’s not all cheery dismemberment:  there’s trouble in the nest.  The siblings to have an uneasy relationship.  I often see them perched on adjacent branches, and when they’re further apart they call out to each other every now and then.  And when one takes off to hunt, the other often falls into line, disappearing suddenly in a simultaneous dive.

But there’s also a certain amount of what might be described in human siblings as petty jealousy.

Yesterday I stood on a chair on the deck for an hour watching one of the sibs engage in  a comprehensive preening session / extended tai chi practice.  I wonder whether this serious self-care might have been the consequence of getting tangled up in one of the humungous org spiders webs stretched out between the trees to catch dragonflies, cicadas and, for the really ambitious arachnid, a passing sparrowhawk.

Preening headless profile tail out crop b&w

… and the headless sparrowhawk

I found the “revenge of the headless raptor” impressive, but his nestmate, looking on from a high branch, seemed rather unimpressed.

Distant top brother looking down b&w

Jeering at silly sibling

But both martial arts and sneering were set aside when the fledgling in the upper branches spotted something tasty beyond the neighbour’s yard.

Juvenile sparrowhawk wings raised square

I’m off…

There was a simultaneous stoop, and then a fracas in the jungle at the bottom of the garden.

White cheeked honeyeater crop

Dinner… a white cheeked honeyeater I prepared earlier

I don’t think the squawking was the work of dinner – an unfortunate white-cheeked honeyeater (rarely seen in our yard.  I wonder why…).  I reckon the ring-ding battle was between the sibs.

The winner landed, very conveniently for me, right next to my washing line, showing the total indifference to human proximity that seems to characterize most young raptors.

 

Sparrowhawk profile left with untouched prey

The lucky sibling with significantly less lucky white cheeked honeyeater

This diffidence did not extend to the presence of little brother or sister though.

Juvenile looking behind for rival

Keeping an eye out

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Juvenile with head turned mouth open amended

 

Just a few moments after the winner landed with their prize, there was another skirmish.  Luck favours the prepared, and this youngster was in position, with wings spread out protectively around the prey like a sort of meat umbrella. Ew, what a nasty image.

The hungry one had another go, and to be honest, I’m not really sure who was successful, since neither juvenile has any distinctive marks (like a scar over one eye or a dragon tattoo or anything) I am completely unable to tell them apart.

Juvenile plucking the prey

Settling in for a good plucking

Anyway, someone had a lovely meal of raw songbird and someone sat nearby looking on and feeling sorry for themselves.

Sibling watching

Luckless sibling looking on at the feast

Nevermind, buddy.  I’m sure there’s be some tiny, tasty, rather slow birds on the menu for you sometime soon.

The backstory of the serial killers in our backyard…

The new generation of sparrowhawks emerges from the nest…

Baby brush turkeys versus nestling sparrowhawks… the battle of the backyard baby birds

The collared sparrowhawks return to our backyard… or are they brown goshawks?

A first glimpse of the sparrowhawks… and a beautiful white goshawk visits the washing line

Things to do with termite nests

lizard in kingfisher nest better crop

Lace monitor in an arboreal termite nest

Happy New Year!

I don’t know about yours, but one of my resolutions for 2018 is to pay a lot more more attention to bugs.  Or rather, insects in general, and how they interact with all the other critters around them.

So the year was off to a good insect-oriented start when I took this photo  just down the hill from the spectacular lookout at West Head in Kuring-gai Chase National Park.

What’s this little monitor doing as she peeps out of this termites’ nest, a few metres up a gum tree?

What’s her story? And what’s she up to with those termites?

Lion island from west head

View north from West Head

 

At first, I thought she might have been after kingfisher eggs or nestlings.

A couple of years ago my bird watching brother told me to keep an eye out for termites nests in trees, pointing out that kingfishers often made the hollows in these “termitaria” to nest in.  Since then, I’ve seen plenty of arboreal burrows on my paddles around the Hawkesbury, and occasionally a sacred kingfisher lurking suspiciously nearby.

Many species of kingfishers, including (to my great surprise – I’m not sure why), kookaburras, often nest in termite mounds.  I had assumed that birds would choose abandoned arboreal termitaria, but in most cases where animals reuse mounds, it seems, the original builders are still in situ when the new residents move in.

Matching kookaburras

Synchronised kookaburras

Unlike other birds, such as the hooded parrots of Arnhem Land, kingfishers don’t wait to build until the mud of the mound is softened by rain.  They do construction the hard way, through sometimes lethal collision flights into outer wall of the nest.  Both members of the pair participate in this headbanging activity until a 25 cm tunnel is dug.  As you can see in the picture of the burrow above, the tunnel slopes downward a little, to help with keeping the it clear of the young’s faeces.  If only dealing with human children’s ordure was a simple as a gently sloping bedroom and hallway, eh?  Once the initial tunnel is dug, the kingfisher sometimes leaves the excavation for the termites to tidy up inside, sealing the interior walls of the nest.

Kingfisher lit profile sharp bigger crop better

New Zealand Sacred Kingfisher

But kingfishers aren’t alone in using termite mounds as a handy place to breed.  I’m not quite sure what was using this big nest near Port Stephens.  I suspect it’s not kingfishers.  Like many Australian birds, they are cooperative breeders, with their youngsters from previous broods helping raise the new babies, but they don’t seem to nest colonially.  As these burrowholes or just access points for some insect-eating predator to have a crunchy snack?

But back to our termite loving monitor lizard.  As a bird-savvy informant pointed out, had my lizard been munching baby kingfisher eggs, the parents would have had something to say about it.  In fact, what I saw wasn’t a nest-raid but most likely the aftermath of a hatching.

Monitor lizard face closeup

Another lace monitor in Kuring-gai National Park

Because, as it turns out, lace monitors  also lay their eggs in termite mounds, using the warmth generated by the insects to incubate their young.  Once the eggs are laid, the lizards lets the termites seal them in, safe from predators in their incubation chamber in the treetops. Or perhaps slightly safer.

No-one seems to research lace monitors – too damn common it seems.  But, researchers studying the related Rosenberg Monitors found that females defended the nests for a few weeks after the eggs were deposited.  Some hard core conflict was observed:

“The most aggressive fighting observed was between a defending female and a marauder, with females fighting males more than twice their body mass. Both attacker and defender sustained injuries, including dislocated or broken limbs; broken ribs; spinal injuries; and severe bites to head, throat, and abdomen” (Rismiller, McKelvey, Green, 2010).

Baby rosenberg monitors dig their own way out of their natal termite heap, but everyone’s a bit vague about how the baby lace monitors escape their birthplace/prison.  Despite the female’s willingness to break a spine or limbs to ensure the safety of their young at the point eggs are laid, herpetologists don’t give goanna mothers a lot of credit for subsequent interest in their offspring.  Some researchers think that the mothers come back to dig their babies out of captivity when the right time comes.  Others seem to think they just happen to be digging randomly in likely-looking termite mounds when they accidentally happen upon their young (Kirshner, 2007).  This sounds all rather implausible to me .

Goanna whole against lichen

Lace monitor in Wollemi National Park

I’m still not 100% clear about what I saw up a tree at West Head.  Was the lizard I spotted was one of the little ones, lolling around in its birthplace after its mysterious liberation.  Or a female spending some time hanging out in the nest, having helped her young to freedom?  I’m just not sure.

One way or another, one of our common-as-muck goannas was doing its thing in its ordinary, fascinating way.  With the help of a multitude of insect Mary Poppinses.

lizard in kingfisher nest distant

The termetarium from a distance

Further references

Kirshner, D. (2007) Multiclutching in captive Lace Monitors, Varanus varius. Mertensiella (16): 403-421

Rismiller, P.D., McKelvey, M.W., Green, B. (2010) “Breeding phenology and behavior of Rosenberg’s Goanna (Varanus rosenbergi) on Kangaroo Island, South Australia” Journal of Herpetology 44(3):399-408. 2010

 

 

 

 

 

 

Sparrowhawk summer

The sparrowhawks in the bottom of the neighbour’s yard have beaten the odds.  Despite the visits of the hungry currawongs and randy cuckoos, two strapping fledglings have emerged from the nest this week.

Two juvenile sparrowhawks trying out their wings

Our days are punctuated by the insistent call of the mother and father hawks telling the teenagers that it’s time to head back to the ridiculously tiny nest for dinner.  And the juvenile’s answering pitiful cries, disproportionate to their galumphing size.  They’re easily as big as their parents even at this early stage.

Photo of juvenile sparrowhawk with its mouth open

Fledgling sparrowhawk talking back to its parent

And early in the morning, the ding-dong battles between the sparrowhawks and the local mob of sulphur crested cockatoos, that wheel across the valley each day to find the tastiest trees and finest roosting places. The hawks have been watchful but apparently unconcerned by the range of large and small humans arguing, gardening, driving, swimming and playing beneath their nest and, as you can see, endlessly photographing their activities.

But the arrival of a crew of a dozen or so seed eaters in their territory was apparently intolerable.  A crested pigeon is the biggest prey sparrowhawks have been known to take, but we’ve seen for ourselves they’re not afraid to send cockies and cuckoos packing.  The cockatoos didn’t take off without a bit of argy bargy but in the end the diminutive predators won the day.

The flock retreated off to our place, and relieved their frustration with some light demolition work on the rotting pine tree in our backyard.  I assumed it was the parents that did the chasing off, but Stephen Debus, who spent a lot of time hanging out in the Bundaberg Botanical Gardens with a digital camera and a pair of young sparrowhawks, seems to think that the young ones like to chase away bigger birds that they couldn’t possibly eat, everything from egrets, darters and ducks to kestrels and even currawongs, their erstwhile enemies.

There’s been an exciting new development in the last couple of days: the littlies are trying their hand with disembowelling.  Young nestlings are fed gobbets of freshly plucked bird flesh, straight from mum or dad’s beak, but this youngster was doing his own kitchen prep.  It took him a while.  Given the eye-claw coordination on display here, it may be a few weeks before this one is hunting on its own.  It seems that taking dinner from the talons of parents mid-air (and maybe snacking on cicadas in between meals) is the next step towards independence.

From the vantage point of our neighbours’ pool, we’ve watched the fledglings practicing their short haul flights (and awkward landings), whine a lot and bicker over food.  In a truly rare sighting, judging from my experience with human children, I even saw one of them give in to his sibling’s relentless complaining and share a meal.

Or maybe what I saw was big sister muscling in on little brother?  Sparrowhawks have distinct sexual dimorphism, and apparently any idiot can tell the smaller males from the females.  Not this idiot!  I look forward to being enlightened by sharp eyed readers.

As you can tell from the recent posts in this blog, I have got just a little obsessed by our in-house raptors these last few months.  Maybe because our four serial killers have cleared the area of other distraction – the usual “house” birds.

No baby brush turkeys this year (hooray!) and the noisy miners have been mercifully silent. But the gorgeous satin bowerbirds have also been thin on the ground, the newly arrived whipbird disappeared suddenly without leaving a forwarding address, and I’ve heard very few of the chocks and clucks of the wattlebirds that make up the usual soundscape of our neighbourhood.

We have about six weeks, it seems, before the young sparrowhawks will disperse, looking for another neck of the woods with the requisite tall trees for nesting and plenty of small gormless birds to ambush from a secret spot in the canopy.

Will the adults stay after the brood has gone?   Will they leave and come back next year?  It seems no one really knows much about the movement of these secretive birds, despite their presence all over Australia, in every habitat but the driest of deserts.

And, if our lovely raptors do leave us, will our usual cast of feathered friends – the nectar drinkers, the seed and flower and lerp eaters – return?

Further references

Barnes, C.P. and Debus, S. (2014) “Observations of the post-fledgling period of the collared sparrowhawk (Accipeter cirrocephalus)” from The Sunbird (2014) 44(1): 12–23

Debus, Stephen (2012) Birds of Prey of Australia: a field guide, CSIRO Publishing

 

More sparrowhawk stories from our backyard

The end of the brush turkey plague? The battle of the baby birds….

There’s a collared sparrowhawk nesting in our garden…. or is it a goshawk…?

and the latest from our backyard: the teenagers start hunting for themselves… Sibling rivalry amongst the young serial killers….

 

 

 

Battle of the baby birds

There’s a festival of death going on in our neighbourhood at the moment.

Several times a day, amongst the robotic clicks of the bower birds and the squawks of the wattlebirds, there’s an insistent high pitched chittering call, often accompanied by the din of freaked out noisy miners.  I’m not 100% sure of its ethological or evolutionary significance, but as far as I’m concerned it’s a signal for me to drop everything and dart up our drive with my camera.  One of the resident pair of collared sparrowhawks – probably the male – has caught some small clueless bird and is perched in our neighbour’s radiata pine steadily eviscerating it.

He rips off the feathers and flings away less tasty bits (check out the beak mid-air above) all the while, often with his mouth full, calling out “Dinner’s up!” to his mate.

For the last few weeks she’s been spending much of her time in a the nest at the very top of another decrepit pine tree in the yard of next house along the way.  Sometimes he flies up to the nest with tasty chunks of flayed bird flesh in his claws, but I’ve also seen her fly in to the designated “disembowling” perch to join him a few times.  Occasionally, she seems to sneak away to do a little light hunting herself.  Risky, though, leaving the nest unattended.

There’s the pied currawong I saw hopping surreptitiously through the branches, warily inching towards the nest, until it was chased off by the indignant parents as it was virtually peeping over the side.  And the pair of cacophonous channel billed cuckoos I caught flapping around the neighbour’s garden a few weeks ago – apparently they sometimes parasitise collared sparrowhawk nests.

But I will be deeply unimpressed if the chicks that come out of that nest are bloody channel billed cuckoos, for all my secret admiration of those giant hornbill beaks and strapping crucifix silhouettes.

Because the sparrowhawks seem to have rid our garden of the plague of baby brush turkeys.

A whipbird seems to have taken up residence this spring.  Needless to say, I don’t have a photograph despite being nearly eye to eye with the noisy bugger once or twice.  So, tiptoeing round my backyard trying to catch a clear shot, I heard a scrabbling in the leaf litter.  “Ah, a baby brushturkey” I thought sagely.

And then it struck me… I haven’t seen a single baby turkey in our backyard this year.  Not one!  Last year, they were sleeping on top of the predator proof cage or standing outside in the daytime, gazing longingly at our flock of little baby chooks.  The year before one wandered into our pocketsized laundry and spent eight hours pacing the two foot long windowsill, failing to notice and thus escape through through the wide open door.  But this year… nada.

Collared sparrowhawks (unlike their lookalikes brown goshawks – so similar that it’s altogether possible they could be our resident raptors) catch most of their prey in flight, bursting out of their lurking places in the foliage to grab little birds on the wing.  But the baby brush turkeys that previously haunted our place do fly, right from the day they dig themselves out of their hatching place in their father’s mound of decomposing leaf litter, and start their life of unnaturally early independence.

So maybe the sparrowhawks have been catching them on those very first short flights from mound to chicken yard.

I don’t hate brush turkeys, but I do hate a having dozen brush turkeys hanging out in my backyard, sexually assaulting my chickens, nicking their food and, given half the chance, eating their eggs.  So the idea of generations of sparrowhawks breeding happily in the neighbour’s trees and keeping the local population to manageable levels is extremely appealing.

I’m starting to wonder if there’s a connection between the familiar sound of chainsaws and the plague populations of brush turkeys in Brisbane and the northern suburbs of Sydney over the last few years.  No dingoes, fewer foxes foxes thanks to baiting, and nowhere much for the local raptors to nest in suburbia these days, the tallest trees victims of fears about bushfires and death-dealing or at least car-damaging falling branches.

But today my endless blurry photos of the neighbourhood raptor nest brought good news: what seems to be a creamy ball of fluff snuggling up to its mum in the distant collection of sticks that is the sparrowhawk’s nest.  Bring on the next generation of brush turkey assassins!

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

 

 

Welcome back, beautiful stranger

Sparrowhawk square crop old

It shows a certain lack of character and imagination to be keen on raptors, but I can’t help it.  I love them anyway.  Even the whistling kites and white-bellied sea eagles I clock every single weekend out in my boat on the Hawkesbury give me enough of a thrill to  clog up my computer’s hard drive with a thousand pictures of them in every conceivable posture and mood.

So two years ago, when I caught this beauty in my backyard, I was beside myself with excitement.  It’s a collared sparrowhawk, one of three species of Acciper found in Australia, along with the very similar brown goshawk and the hauntingly beautiful grey goshawk.  So beautiful that on my one and only encounter with one (whilst pegging out the washing) my camera fainted and so in its barely conscious state was only capable of producing a groggy quasi-mystical image of the world’s only pure white raptor.

I know our beautiful visitor in 2015 was a sparrowhawk and not the very similar looking brown goshawk, having been schooled on the key differences.  Brown goshawks are slightly grumpier and more threatening looking, with a beetle brow and chunkier legs.  Both species, it is said, waggle their tail on landing, but the sparrowhawk does it a tiny bit more rapidly.  As my brother, a much more expert bird watcher than I am, points out, this has to be the most arcane and pointless advice for distinguishing two very similar looking birds.  “Sorry lads, the video of your tail waggling was slightly out of focus.  Can you just circle round and land side by side on that branch again?”

Collared sparrowhawks also have another feature – the absurdly long middle toe of the collared sparrowhawk, used to grip its prey while it systematically plucks them (starting at the vent) and then devours them.  It’s moments like these you’re grateful not to be a sparrow or a silvereye, isn’t it?

But is that enough to tell the difference between a goshawk and a sparrowhawk?  Both apparently have these long middle toes – the sparrowhawks’ toes are just longer and more delicate.

There are other differences too.  Goshawks have a rounded tail, and a smaller eye.  So is it welcome back stranger… or good to see you, lifer?

Both the collared sparrowhawk and the brown goshawk are widespread through their range in Australia and New Guinea – they can be found in arid areas as well as woodlands and suburbia.  They are one of the few raptors that will perch and hunt in gardens, as I saw today.  The fact that they’re partial to a snack on introduced birds like sparrows, starlings and newly hatched chickens (gulp!) may be one reason why they’re considered “of least concern” to people who worry about the current mass extinction event.

But still, they’re not exactly common. Numbers declined from the 1940s through to the 1980s thanks to DDT, although the effect of this insecticide – thinning the shells of eggs – seems to have been less dramatic for them than peregrines and some other raptors.  Loss of habitat for the small birds that sparrowhawks like to eat and competition from pied currawongs that will (somewhat implausibly to my mind) attack both adults and chicks are other threats.

It’s been a long couple of years since that last wonderful visit.

But over the last few days there’s been a new sound from the decrepit pine trees that stand (or should I say lean) between our place and our neighbours’.  At first I thought it was a whiny juvenile wattlebird begging for a feed – the call was a kind of feeble high pitched kik-kik-kik-kik.  And then I saw a creamy coloured bird with wide striped wings and a blunt head, superficially like the “green” satin bowerbirds that hang around here all year round scrounging off my chilli bushes and demolishing my bean plants.

But there’s something distinct and decisive about the way raptors fly.  I eventually got a good look as the bird chilled out in the trees, waiting to ambush passing little passerines, which they catch on the wing.  I’m really hoping they have a taste for noisy miners.

good sideways distant crop wide

These really are very low-key birds.  “Often lives unnoticed in mature-treed suburban parks and gardens” one ornithology site comments about sparrowhawks… “easily overlooked”.  Having spent quite a bit of today staring slightly hopelessly into the naked branches for an immobile, unconcerned and well camoflaged bird of prey I can confirm this.   “Trusting and approachable“, the Peregrine Trust’s turn of phrase for a collared sparrowhawk, seems like a slightly embarrassing description for a predator.

Sparrowhawk profile crop tighter still

A gorgeous profile on display.  One very chilled out bird.

The grumpy reputation of Brown Goshawk is apparently not just a consequence of their Resting Bitch Face.  They’re also apparently quite aggro around the nest.  True to form, sparrowhawks are said to be calmer.

Perhaps this parental behaviour will be the solution to my ID problem.  There’s a nest made of sticks high in the neighbour’s pine tree, a spot I saw the sparrowhawk returning to several times today.  If there’s anything better than grown up raptors in your backyard, it’s a clutch of baby raptors.

nest rop

Could this be a sparrowhawk nest?