Category Archives: breeding

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January 2, 2022

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breeding, mating, Native birds, nesting, raptors

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When too much (raptor) sex is barely enough

Sparrowhawk lurking in the liquidambar

Over the last couple of months I’ve upped my bird nerd quotient a notch.  Having already distressed my teenagers by revealing that the jolly bird calls they were hearing each morning were the sounds of our resident raptors in flagrante, I have taken my prurient interest in the intimate lives of avians one step further.  At last I have some good pictures of sparrowhawk sex.  If you don’t want to see them, look away now.

Sparrowhawk sex
It’s chatty

In my defense, our resident pair were at it relentlessly for three months. When I say relentlessly, I mean at least four or five times a day.  Not so much morning noon and night, more early morning, morning, morning, morning and occasionally late afternoon.  It was hard to ignore, although I found my colleagues less intrigued than I expected when I drew their attention to the ambient sounds of bird sex in the middle of zoom meetings.

Because I’m a worrier, even before living through a pandemic, hearing avian coupling for month after month ended up making me feel quite anxious about the reproductive systems of our pair. Why so much sex?  One of my Gen X pals suggested drily that perhaps they were very young.  Had they failed to produce eggs and were keeping at it until something happened?  Or were they just enjoying themselves??  Are sparrowhawks the bonobos of the raptor scene?  Strangely, the published literature has failed to help me with this question.

This unrestrained mating duet somehow suggests an element of enjoyment but I’m no doubt anthropomorphising.

A typical “bout” as D.H.Lawrence might have put it, would usually start with the female sitting high in my neighbour’s pine tree calling for her mate. Often she was in possession of some prey, and demonstrated a bit of multitasking by intermittently ripping out its entrails between summons.

Female sparrowhawk calling the male

Sparrowhawk tearing prey

Eventually the male would turn up, perch on a nearby branch and then hop over to engage in some avian sexual congress.  My attention during this period was directly primarily towards the snacks.  Would the female share a hunk of flesh as a bit of a “thank you” to her partner for, as it were, coming on command?

Sparrowhawk pair after mating

It appeared not.  I watched the whole sequence of activities a few times, and while the male would lurk nearby for a while, possibly eyeing up the gobbets of LBB flesh in the claws of its mate, I never once saw the female share the spoils.

Female sparrowhawk with food

On this occasion the female sparrowhawk flew off with a large chunk of uneaten prey (mostly, as you can see, legs).  At the time, I was hoping she might be heading toward the nest to feed some hungry chicks.

With no post-coital snacks on offer, the male often ended these encounters by gathering material to renovate the nest.  Trying to work out what was going on, I struggled to imagine him somehow inserting these liquidambar leaves around some eggs or wriggly, begging chicks.  I began to suspect this pair did not quite know what they were doing.

Sparrowhawk with nesting materials

Despite neighbourhood excitement every time one of the pair flew towards the nest with some prey, it seems that this year there won’t be any sparrowhawk fledglings doing yoga in the trees or playing by the swimming pool.  Throughout this cool and rainy La Nina spring, there was mating and there was nest building, but nothing came of it.  Perhaps the nest blew away in one of this year’s storms. Perhaps the late appearance of the cicadas meant fewer easy snacks.  Perhaps the pair just simply didn’t produce any fertile eggs.  All I can say is, they certainly tried.

Come back next year, my lovelies.  I might even give you more privacy this time.

 

More raptor tales from our Berowra backyard

Death and sibling rivalry

The very big fish

Crested hawks for Christmas

Motherhood on a windy day

An eagle in suburbia

The battle of the baby birds

Cartwheels and company: the young eagles

Loves and leaves

Sex, nests and dogfighting

Encounters with eagles

 

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August 8, 2021

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breeding, national parks, Native birds, nesting, waterways

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Warbling in lockdown

Kayak on still river water at dawn with reflections showing the sky

Six weeks into a Sydney lockdown.  Everyone confined to their homes with occasional outings for food and exercise no more than a few ks away.  I feel super lucky that this bit of Dyarrubbin still falls within the 10 k radius I’m allowed to stray from my house. Berowra Creek, at the end of my street, is super quiet at the moment, the houseboats rocking empty at their moorings, jet-skis banished – only the locals heading out in ones or twos for some fresh air.

It seems fitting that the “feature wildlife” of my escape to the river last weekend was also a local – Sydney’s only endemic bird, origma solitaria, the rockwarbler.

Sydney’s only endemic bird – the rock warbler

These little birds are only found within 250 km of Sydney, hopping around mostly on Hawkesbury sandstone, though I’ve hear they also pop up on the limestone and granite, where it is to be found.  Their range on the coast extends from Mollymook  to Raymond Terrace, and they can be found as far west as Orange and in the north can be found up in the beautiful Coolah Tops National Park, according to the CSIRO Australian bird guide favouring “exposed, dissected rock outcrops…from coast (including sea cliffs) to high plateaus  of the ranges” (2017, 340).

Rockwarbler on a mossy rock

Rockwarblers are not uncommon – despite their restricted range they’re flagged as of least concern, conservation-wise – though they don’t appear to inhabit cities like Newcastle, Sydney or even Wollongong or Nowra.  On my noodling 12 k paddle last weekend I spotted one pair busily feeding and nestbuilding on rocks by the waterside, and then, having tuned my ear to their high pitched calls, spotted another pair doing much the same, on the return journey.

I don’t see them on every trip out but I’ve observed them behind golden beaches on Cowan Water and in rocky bays near Dangar Island, and even in one of the spots  at Berowra Creek with the most foot traffic, at Washpool Creek where the Great North Walk meets the estuary.

The rockwarbler is an unremarkable looking little bird – “a small, plump, dark brown-grey bird with a cinnamon-tinged face and forehead, a dull white throat speckled black, reddish-brown underparts”, almost the definition of the LBB – but has some interesting habits.  It makes pendulous domed nests that hang in darkened overhangs and caves in the rocky terrain it prefers – apparently its common name used to be “hanging dick”.  Who says all folk wisdom  needs to be kept alive, eh?

I spotted my first rockwarbler for the day collecting what looked like nest material – roots and possibly spider webs  in the exposed root system of toppled trees on the shoreline. She flew off intermittently into a group of boulders behind some casuarina trees – I couldn’t get a clear shot of the crevice she seemed to be returning to, so no photo of a hanging dick, for which you might well be grateful.

Despite all this, I’d like to get a glimpse of a nest – the description in Birdlife’s online site have a hard core goth appeal:

Made from grasses and plant fibres and coated with spider webs, [the nest] is attached to a rocky overhang or roof of a cave by spider webs, which the bird hammers into place with its bill. They are then covered with saliva to hold them in place

You can see in these pictures that the spot I saw my first pair of rockwarblers has been a important place for humans as well as non-human animals for thousands of years.  The soil here is thick with oystershells, left by the custodians of this country over the centuries, and now woven into the earth in scores of places right along the shores of Berowra Creek.  Everywhere you look around here there’s a midden.

Rockwarblers look a little bit like northern hemisphere robins and seem to have a similar outgoing personality – “confiding” in the words of the CSIRO blue bird book.  This bird and its mate, that soon arrived on the scene, didn’t seem particularly disturbed by a kayaker loitering nearby with a camera, and I managed to drift quite close while they scoured the rocky shore for largely invisible food.

I’ve read that rockwarblers are primarily insect eaters although Carol Probert has reported seeing nectar drinking in some she watched in the Blue Mountains. No evidence of this here but there seemed to be plenty to eat.  This pair traversed the rocks briskly, picking mysterious things from amongst the moss, and even dipping beaks into the little bowls comprised of previously-opened mollusc shells on the rocks.  I’m not sure  if the rockwarblers were scrounging for critters that had found a home in these tiny rockpools.

A second pair of rock warblers looking for food together

There were plenty of insects about in the lee of the rocks, but i didn’t see any of the birds I watched that morning snatching a snack from the air, despite the temptation.

What I did see – once with each pair of birds – was what I think were nuptial gifts – one bird feeding the other snack, perhaps with romantic intentions.  I stress I did not witness any subsequent feathered intimacies but with birds you blink and you’ll miss it, so that doesn’t necessarily mean a lot!

Here’s pair number one, coming beak to beak.

And the second pair

I think I can see a insect leg sticking out from the crumb in the beak of the bird with the tuft of feathers on its back.  I guess these scenes could have been adults feeding juveniles, which look similar to the grown-up rock warblers, only paler in colour, but I didn’t hear any pitiful calls from the recipients and given the time of year – roundabout the beginning of breeding season for many birds – a romantic gesture seems a bit more likely.

Rockwarbler happily feeding

The rockwarblers were pretty friendly to me but also to the other little birds hopping around the nest area, particularly a family of variegated fairywrens that seemed to follow them as they hopped about round the edge of the water.  The warblers kept their feet mostly on rock, the wrens mostly flitting from twig to twig in undergrowth nearby. If there’s dietary competition between these little birds, it’s a very friendly one.

In fact, I suspect this was more like the mixed-flock foraging that have been noticed in many parts of the world in wintertime, when different species of small insectivous birds move around feeding as a group.  Maybe the rockwarblers’ hopping stirred up some flying insects for the wrens to eat?  Some researchers have found that variegated wrens, sometimes hang out with “friends” from other species whose territory overlaps with their own, sharing the defense of that territory, travelling and foraging together. This benefited the wrens a lot – they “spent more time foraging, were less vigilant [and] had greater first-nest fledging success” (Johnson, 2018, 821).  I wonder if the wrens were as friendly as this with my rockwarblers?

Male variegated fairywren
jenny variegated fairywren
silvereye in the casuarinas

The atmos not so friendly amongst the waterbirds feeding nearby.  I watched a whitefaced heron repeatedly asserting dominance over a striated heron on a sequence of estuarine patches, as I trekked back the put-in.  Berowra’s ubiquitous waders are higher up the pecking order than ubiquitous lurkers it seems.

Striated heron irked enough to walk away
Striated heron finally gives up on this patch of shoreline

And then, just as I turned the corner to the marina, high over all, the alpha local of these lands.   A wedgie soaring silently, surveying its domain.

 

References

Davis, William M and Recier, Harry “Winter mixed species foraging flocks in acacia woodland of Western Australia” Corella, 2002, 26 (3), 74-79
Menkhorst, Peter; Rogers, Danny; Clarke, Rohan; Davies, Jeff; Marsack, Peter; Franklin, Kim The Australian Bird Guide, 2017 CSIRO Publishing
Probets, Carol ; Palmer, Grant ; Fitzsimons, James “Nectarivory in the Rockwarbler ‘origma solitaria’ Australian field ornithology, January 2019, Vol.36, p.34-35
Smith, Peter ; Smith, Judy “Re-use of a rockwarbler ‘origma solitaria’ nest over a 13-year period” Australian field ornithology, 2012-06-01, Vol.29 (2), p.77-82
Other locals in our backyard
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December 31, 2020

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Backyard birds, breeding, cicadas, competition, Insects, mating, nesting, predation, raptors, territoriality

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Crested hawks for Christmas

Every birdwatcher has a list of sightings they dream about (if that sighting is accompanied by a National Geographic front-cover-worthy picture all the better).  For the cognoscenti – sophisticated, proper twitchers – this list seems to feature rare, endangered or hard to spot critters, that may or may not be kind of boring to look at.  But for the crass newbie like myself, bling is important. Flashy, that’s how I like my bucket list birds.

For a long time, a decent look at the gloriously multi-coloured (but annoyingly canopy dwelling) spotted pardelote was top of the list.  A camping trip to the fabulous Wolgan Valley a couple of years back ticked that box.  Worth sweating my way up a hill to look down on the magic of the diamond-bird.

Spotted pardelote

Obviously rainbow bee eaters were on also on the list, until my parents moved to Bingara in on the northern slopes of NSW, a town where grey nomads and bird nerds duke it out for dominance in the local economy.

Pair of rainbow bee eaters

Since then, my top two have both been raptors.  There’s the black shouldered kite with its glorious red eye and hauntingly regular presence along highways. I see it often on long road trips, hanging out near boggy pasture land, but getting a photograph seems to require a willingness to pull the hand brake on at high speed in the middle of a major road.  I’m not saying I won’t do that, but I’m still working myself up to it.  And then there’s the absurdly excellent Pacific Baza.

Stunning golden eye – tick.  Dramatic black-and-white belly stripes – tick.  Elegant flight, even acrobatic during the mating season – tick again.

And, absurdly, a crest – its nickname is the “crested hawk”.  Does it get any better than that?  I think not.

I was hugely excited when I spotted what I thought was a baza in our neck of the woods a few weeks ago – zipping past and disappearing into the leafy top of a liquidambar tree.  Birds seem to be attracted by a pheromone released by amateur photographers who are not carrying a camera.  Certainly that was the case on this occasion.  Lacking any visual evidence of the encounter, I figured it was a wish fulfilment sighting.  Probably one of the collared sparrowhawks, also stripy chested canopy dwellers.   They’ve been back on the scene at our place over the last month or two, hanging out in the top of the neighbour’s pine tree, bragging about their kills and having brief and frustratingly hard to photograph sexual encounters first thing in the morning.

Collared sparrowhawk hiding in the foliage of a liquidambar

But this week – a late Christmas present.  My outstanding neighbours Laura and Steve texted to say that the mysterious bird they had previously seen lurking in a melaleuca tree had made at a guest appearance by another neighbour’s pool, and been IDed.  It was a Pacific baza.

It’s a miracle that I didn’t get hit crossing the road as I raced over to their place.

Adult Pacific baza

The trip to casualty that could have ensued would have kept my from not just a single baza but a little family – a pair (I think) and a large and whiny fledged chick.  Naturally, they were lurking in the very top of the tree, and of course, my skill-set with my flash new camera meant that my career as a natural history photographer is not going to take any great leaps forward.

Adult Pacific baza avoiding eye contact with a juvenile

Blurry as it is, I interpret the body language of the parent here as indicating an unwillingness to provide further snacks.  We saw both adults make a few short flights, and at least once definitely offer the youngster some prey.  The juvenile whined without interruption, inching along the branch towards the adults, ducking its head and restively half-opening its wings.  This parent avoided eye contact and eventually flapped off to a separate spot in the tree.   A couple of weeks after they leave the nest, apparently,  juvenile bazas stop getting food provided by their parents, so I guess this was what was playing out here.  Baby Baza was certainly less than happy.

Juvenile baza (I think) in a huff

To say I was ecstatic to see the family of bazas within 100 metres of my front door would be to underestimate my degree of excitement. But then a troubling thought struck me… would the presence of the bazas harsh the buzz of the sparrowhawk pair that I’d seen canoodling on my side of the street?  The pair appeared soon after a fierce storm that tore some big branches in our backyard and might well have trashed a nest somewhere down the road.  Would the appearance of the bazas spoil the chance of a late-breaking bit of nest building?

Juvenile baza showing crest and aggro

Like Pacific bazas, sparrowhawks spend a lot of time in the treetops.  They’re ambush hunters, lurking in amongst the leaves ready to burst out and pluck small birds from the sky.

Looking for prey
Sparrowhawk hunting from a pine tree
Sparrowhawk ignoring dregs of its last meal

They’ll take sparrows (perhaps unsurprisingly), mynahs and miners, mudlarks and wattlebirds, even birds as big as crested pigeons or crimson rosellas. Here’s a pic I took recently of a sparrowhawk trying to choke down the remnants of a leg of a bird.  See the toes poking out of its beak?  I watched it pacing up and down on the branch, wiping its beak repeatedly and generally looking a bit agitated.  I note that the left over leg remained untouched and I can kind of understand why.

When something gets stuck on the way down

Maybe its not surprising after this kind of experience that a sparrowhawk might want to ring the changes, diet wise.  And in fact, sparrowhawks won’t say no to a bug or two.  A Canberra study found half of sparrowhawks’ prey, by the numbers, were snails, spiders or insects, with Christmas beetles and cicadas a particular feature.  All those insects weren’t too filling – they made up only 2% of the biomass.  But still, that interest in insects could them into competition with bazas, which eat fruit, frogs, lizards and snakes, grabbed from the foliage at the tops of trees, but especially like stick insects.

Yet another thing to inspire delight in bazas – an eccentric specialist diet.  When I was looking at this critter in the Berowra train station, I wasn’t thinking “if only I ripped that to bits it would make a toothsome snack for my children”.  But if I was a baza, I would have been.

Stick insect

However, larger insects are a favourite of Pacific bazas, while sparrowhawks seem to go for nothing bigger than a huntsman or a cicada.

Disappointingly, the bazas have disappeared from the paperbark in Steve and Laura’s drive, for all its proximity to a refreshing backyard pool and ample opportunities for hunting in the tops of tall trees, undisturbed by competition for their favourite phasmids.  They’ll probably be nearby – these raptors aren’t migratory and Berowra sounds pretty close to their ideal habitat:

tropical and sub-tropical forests and woodlands, largely within 300km of the coast. In the breeding season they frequent tree-lined watercourses, rainforest, sclerophyll forest and tall woodland, but range widely following nesting to lower ground, when they may visit urban parks and gardens.

One birdwatcher in Queensland followed the reproductive fortunes of a pair of bazas as they nested in a series of different trees within a couple of hundred metres of his house on his property for a decade.   So, no National Geographic cover photo as yet but I remain hopeful.  2020 really was a dud year but with the crested hawk in town, who knows what fine things could be in store for us in our backyard next year.

No, don’t look back to 2020 sparrowhawk! Forward, always forward.

Raptor encounters in our neighbourhood

Sex, nests and dogfighting – sparrowhawks set up house in our local pinetrees

Sparrowhawk sibling rivalry – baby serial killers learn to hunt

An eagle in suburbia – a wedgetail on Berowra Creek

The very big fish – sea eagle vs mulloway

 

References

  • Briggs, Allan (2018) “Breeding biology and behaviour of a pair of Pacific Bazas ‘Aviceda subcristata’ in central-coastal Queensland over 10 years”. Australian Field Ornithology, Vol. 35, 2018: doi: http://dx.doi.org/10.20938/afo35095101.
  • James, P. (2004). The breeding cycle of a pair of Pacific Bazas Aviceda subcristata in south-eastern Queensland. Australian Field Ornithology 21, 133–140
  • Olsen, Jerry, Judge, David, Trost, Susan and Stephen Debus (2018) “Diets of breeding Brown Goshawks Accipiter fasciatus and Collared Sparrowhawks A. cirrocephalus near Canberra, Australia and comparisons with other regions and raptors” Corella, 42
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December 17, 2018

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Motherhood on a windy day

Kid with mum distant 2 wide crop

Last year two collared sparrowhawk fledglings made it out of the nest high in our neighbour’s pine tree.  This year it was just one.  It’s been a lot quieter around here.  No squabbling over snacks.  No shuffling along branches side by side or pratfalls high in the canopy.  No hightailing it after a sibling chasing a feed.

There’s been more adult and parent bonding, though. I rarely saw the adults and offspring together last year.  But a few weeks ago, in windy weather, I got to see them hanging out low in the trees by our drive, sheltering from the tossing branches.

Juvenile against bark close crop

The juvenile looked, by turns, absurdly sleek and adult, and fluffy and completely gormless.  Mum (or dad) seemed to be wrestling with the same conceptual problem – how grown up is this chick really?

Typically when the sparrowhawks catch a juicy white-faced honey eater or wattlebird chick, they call out, over and over again.  I’m not sure if this the dinner bell for partner or offspring, or just triumphant territory claiming.  They swiftly pluck the small bird they’ve caught and then gorily and fairly rapidly consume it.

But on this particular day, the adult hawk sat very still, prey gripped tightly, not taking even a bite.  The youngster lurked awkwardly nearby, apparently not sure what to do next.

Kid with mum lower

Eventually mum (or dad), probably irked by the local amateur photographer, flew to a higher perch in the trees.  But her prey, plucked, pink and gleaming, was still untouched.

Mum with prey 2

She was waiting. Eventually Junior flew up to join her.

He still seemed clueless about what she wanted him to do – as indeed I was.  I’m willing to have a guess, though.

Adult sparrowhawks start by feeding their young little shreds of meat – the avian equivalent of pulled pork, I guess.  I have heard the adults teach the fledglings to catch little birds mid air by dropping little snippets of prepared flesh to them on the wing.  This youngster was definitely not in possession of that skillset.

Mum and kid with prey high 3

But I think dad (or mum) was trying to give the not-so-little little one a low-stakes chance to prep the dish for her (or him)self.  But it certainly wasn’t happening on this occasion.  Young blood had a good look, then stumbled past and took off, not even having a tiny go at flesh-tearing.

Juvenile from behind looking over shoulder crop

To be honest, I’m really pretty worried about this young one.  I’ve been working from home a lot lately, and every morning, I hear sparrowhawk calls, and I race up the drive with my camera.

But it’s just the adult I see, calling and calling and calling.

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

 

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…?

Our sparrowhawk summer

The teenagers start hunting for themselves… Sibling rivalry amongst the young serial killers….

Sex, nests and dogfighting

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December 19, 2017

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breeding, Death, egg laying, Garden trees, nesting, raptors

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Sparrowhawk summer

Adult sparrowhawk telling the kids that dinner is on its way

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.

A juvenile sparrowhawk watching the demolition work with interest
Cockies in retreat

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.

Juvenile ripping a small bird to bits
… but keeping an eye on me at the same time
Fledgling sparrowhawk still aspiring to elegance

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.

Oops. Failure to land.

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.

Red wattlebird in times gone by.
The usual bird visitors enjoying sunset over Sam’s creek

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.

Young sparrowhawk in hunting position
Adult sparrowhawk hiding in the canopy ready to pounce

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….

 

 

 

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November 12, 2017

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Biodiversity, breeding, Brush turkeys, Death, egg laying, mating, Native birds, nesting, predation, raptors

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Battle of the baby birds

Male sparrowhawk taking off with prey. Photo by Josh Matthews.

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.

Female sparrowhawk getting stuck in
“Beak? Yuk” – see above the hawk’s head
Dead wattlebird being sized up

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.

Sparrowhawk calling for his mate
Mid-meal call

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.

Currawong after the sparrowhawk nest
Collared sparrowhaw about to fly

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.

Pair of channel billed cuckoos

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.

Baby brushturkey in the backyard

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.

Baby brush turkey hanging out with baby Winter the Leghorn
Baby brush turkey being liberated from the laundry

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.

Baby brushturkey on an early flight
Dad and mound
Eight hours into the vigil on the windowsill
Much mourney Treasure the Sussex and an entourage of brush turkeys
Just a few of the even dozen visiting in the last few years

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!