Tag Archives: collared sparrowhawks

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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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October 16, 2021

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predation, Predators, raptors, Satin bowerbirds

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The butchers and the flower eaters

Closeup of sparrowhawk with prey against background of bark

Collared sparrowhawk with prey

The crowd of noisy miners  squabbling right outside my window had me jumping straight out of bed and reaching for my camera.  More than the usual disputes for territory with the “house” little wattlebirds, this had the distinct vibe of a predator in action.  And sure enough there was one of our collared sparrowhawks, perched on a low branch less than 5 metres from my front door, wrapping its laughing gear around what looked like one of the miners.  They weren’t taking the dismemberment of one of their own lying down.  The sparrowhawk stayed very very still while a crowd of miners scolded and divebombed  it. But eventually it was time to do some butchery.

After a certain amount of viscera had been hurled around, the miners obviously decided that Bob wasn’t looking likely to rejoin the flock.  While I was watching, one hold-out had a final swoop – the sparrowhawk ducked and called out repeatedly for moral support.

Sparrowhawk calling for its mate

Calling for moral support

I’m not sure if it was the male (smaller, more bomb-able) or the female (generally chattier) calling for help.  Male and female sparrowhawks really  similar, even though when you see them side by side the females are distinctly larger.

A pair of collared sparrowhawks, showing the female is much larger than the male

Sparrowhawk pair

No chance of comparing sizes on this occasions – calls for help were completely ignored. Eventually this most belligerent miner of the group wandered off to harass some less aggressive passers-by.

I’ve been a vegetarian for over thirty years but this kind of gory scene doesn’t bother me one little bit.

Sparrowhawk with prey

Especially when it’s a noisy miner biting the dust.  I had a look in my files to see if I had any good pictures of miners but nada.  I’m not even that keen on their cousins the more elusive bellbirds – despite the atmospheric calls, like their cousins they’re colonial, driving other bird species out of their patch.  Groups of bell miners can even, somehow, execute the trees they inhabit.

I’ve been a bit surprised at the distaste of lots of bird lovers for scenes of raptor butchery, when I’ve definitely smelt the smoke of barbecues drifting from their backyards.  Where’s the solidarity with other top predators?  Plenty of people seem to be fond of cats.

Thinning out the noisy miners is  not the only environmental service provided by the local birdlife.  The wattlebirds make short work of the window spiders, hovering like hummingbirds and plucking them from the tangled webs, that according to my kids, “make it look like Halloween at our place the whole year round”.  The chooks clean up ticks and fruit fly larvae.  And I captured a juvenile satin bowerbird earlier in the year making a dent in the local caterpillar population, with the help of mum.

Adult female bowerbird feeding juvenile with caterpillar

I don’t mind when the bowerbirds do some tip pruning on my liquidambar tree.

Bowerbird silhouette in the top of a liquidambar tree

But I’m a bit less keen on the scarlet blooms of my “running postman“, few and far between, getting munched, even if that means the local bowerbirds are subscribing, like me, to a plant based diet

Because they’re so famous for their decorative skills, whenever you see male satin bowerbirds collecting pretty stuff, you expect them to be thinking about their bowers.  Like this visitor who I’m pretty sure was sussing out the “bowerbird blue” backyard tennis pole.

But I’m pretty confident that the Kennedia rubicuns flowers this bowerbird was collecting were for snacks, not for interior decor.  How do I know?  Well, some researchers got satin bowerbirds to choose their favourite colour of Froot Loop.  Turns out, even though bowerbirds prefer blue and violet things as decorations in their love-shacks, given a choice of Froot Loop for a snack (not something that happens a lot, admittedly), they’d rather eat red and yellow ones.

Why, you might ask, were scientists trying to goad satin bowerbirds into eating Froot Loops?  Well, it was all about the evolution of preferences for a blue-hued bower.  Researchers were testing whether male bowerbirds evolved to decorate their bowerbirds with blue things because female bowerbirds liked blue snacks (Borgia 1987).  Presumably they came up with this idea in a study with rump steaks, potato wedges and steamed broccoli framed and hung on the walls.

A black male satinbowerbird sitting on a branch looks curiously at the camera

These researchers already had a pretty good idea that they wouldn’t find red Froot Loops in bowers – I know this because of a series of experiments that seem to me to essentially be an interspecies wind-up.  One of these tests involved goading male birds by trashing one half of their bowers and seeing what would happen.  Another, capitalising the “intense dislike for red objects at their bowers”, involved “a clear container over three red objects and quantif[ying]the time for each male to remove the container” and “super-glue[ing] a red square tile to a long screw and fix[ing] the tile into the bower platform and ground below so that it could not be physically removed” (Keagey 2011 1064).  They also recorded the male bower-birds’ come-on lines – their mimicry of other birds – and spied on them to see if they got lucky. I don’t want to perpetuate any stereotypes, but is it a coincidence that the guy running this lab sports the name “Borgia”?

Juvenile satin bowerbird perched in a tree seen in profile with a background of green leaves

Turns out being smart improves your chances of getting lucky (if you’re a male satin bowerbird, anyway) but being very worried about red things in your bower not so much.  Also, bowerbirds are capable of making a clear distinction between decorative items and food.

Somehow this doesn’t seem so odd to me. It’s humans, it seems to me, who don’t seem to be able to adequately categorise their Froot Loops.

A sparrowhawk in flight against a blue sky

References

Jason Keagy, Jean-François Savard, Gerald Borgia (2011) “Complex relationship between multiple measures of cognitive ability and male mating success in satin bowerbirds, Ptilonorhynchus violaceus” Animal Behaviour 81 1063-1070

Gerald Borgia, Ingrid M. Kaatz & Richard Condit (1987) “Flower choice and bower decoration in the satin bowerbird
Ptilonorhynchus violaceus: a test of hypotheses for the evolution of male display” Animal Behaviour, 35, 1129 1139

Matthew Mo (2016) “Diet of the Satin Bowerbird Ptilonorhynchus violaceus in the Illawarra Region, New South Wales, Australia” Corella 40(2)

 

More stories about the sparrowhawks in our backyard

Death and sibling rivalry

Motherhood on a windy day

The battle of the baby birds

Loves and leaves: our sparrowhawks do some nestbuilding

Sex, nests and dogfighting

 

And more about our bowerbirds

The bowerbird bachelors

R2D2 in black and white

Gymnastic bees, virgin fruit and the birds that ate spring

 

Adult female bowerbird feeding juvenile red berry

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August 22, 2021

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Backyard birds, national parks, Native birds, nesting, Plants that attract wildlife, raptors, territoriality

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Loves and leaves

Burn-off sunset.

Yet more lock-down luck.  Company, space, a rambling garden desperately requiring attention, three national parks in walking distance and enough devices to make home learning while working full time quasi-feasible – I already have plenty to be grateful for.  And now, the collared sparrowhawks are back, getting friendly in the neighbour’s pine tree.  They have perfect timing.  It’s just at that point in the lockdown – eight weeks in – when even the most avid homebody/hoarder is running out of distractions.  I’m not saying that trying to get a photograph of the local raptors having sex is my only reason to get out of bed in the morning, but it is a reason.

Sparrowhawk in profile

Morning does seem to be the time for it.  No pictures – this is a family-friendly blog, after all (nothing to do with me being slow on the draw with the zoom lens).  When the sparrowhawks are around, we usually hear them soon after sunrise.  There’s relentless calling from near the top of a tree – mostly, I think from the female.  The male perches, in a diffident kind of way, in a nearby branch.  Then they’re at it, with a brief distinctive flurry of calls.  Afterward, the male shuffles or flaps a distance away on the branch, studiously avoiding eye contact.

Sparrowhawk demanding attention

The one time I managed to watch the process from go to whoa, afterwards the female chilled out in more or less the same spot high in the pine tree, catching the morning rays, and keeping an eye out for small bird snacks.

Meanwhile, what I think was the male (though this might be a gender stereotype), started attempting some DIY.  Collared sparrowhawks build a shallow nest of stick, high in the canopy, and line it with fresh leaves each year.   This pair seem to be using the same spot in the very top of the neighbour’s tree, notable for its inconvenient lack of a line of sight from my place.

Watching the male gathering construction materials, I’m once again reminded of the limitations of the sparrowhawk’s modest beak and  delicate legs for this kind of building work.  The bird seemed to spend a lot of time eyeing up flimsy looking twigs and then flailing around with its wings in an attempt, mostly unsuccessful, to break some bits off.

Sparrowhawk with wings out on a delicate branch
Sparrowhawk in profile in the dead branches of a pine tree

 

As you can see, this bird had a red-hot go at getting some twigs from dead branches on one of the usual pine trees.  Eventually, however, the nest-building one of the pair got a bit experimental.  The liquidambar in our front yard – stripped of its leaves by winter, and not so good for ambush hunting – got a visit, solely for construction purposes.

Sparrowhawk trying to grab some twigs for the nest

However, some of the neighbour’s shrubs with thin whippy stems and fine needle-like leaves and seemed to be nest-material of choice.

The bush of choice for sparrowhawks but not bird photographers

Even so, the process was neither dignified nor ubiquitously successful.  These photographs are both fails.  Photographic fail – frustrated nest builders crashing around in the shrubbery are not an easy capture.  Also, nest building fail – neither of these twigs made it back to home base.  I did, however, see more success on another round of visits to this same bit of greenery the next day.

Failure to launch with this one
Reaching down for a twig

And they’ve kept at it, with occasional success.

Sparrowhawk with stick
Sparrowhawk taking off with nestbuilding materials

Watching the nest-reno in action has made me reflect on our luck in having these gorgeous critters hanging out nearby – and  on what kinds of habitat create that kind of luck.  Sparrowhawks need tall trees to nest in. This pair (assuming it’s the same one returning each year) nest in one pine tree, and use a sequence of three others nearby as regular hunting spots.  Thanks to lots of greenery, we have loads of undemanding smallish birds on the premises of the right size for raptor snacks – little and red wattlebirds, chicks of the ubiquitous brush turkeys and, of course, loads of bloody noisy miners.

Little wattlebird facing off with a kookaburra
Red wattlebird in autumn leaves

I’ve definitely seen the sparrowhawks devouring birds that we don’t see at our place though – I’m sure they hunt in the national park that’s 500 metres down the hill.  Here’s one of the fledglings from a couple of years ago, chowing down on what I think is a white cheeked honeyeater – I’ve never seen one at our place, but they’re pretty common in the bush not far away.

Juvenile sparrowhawk protecting its prey
Fledglings eating a new holland honeyeater

In the two seasons when they successfully raised chicks, the fledglings seemed to practice short hop flights from one pine to another.  The liquidambar in our yard is an occasionally hunting spot in summer, and I do wonder if the cicadas that appear to feed on its sap in mid-summer offer useful meals for the chicks.

And then there’s the necessity for nest-lining trees with appropriately flimsy branches.

Sparrowhawks are generalists and live all over the place – everywhere except the most arid regions of Australia.  So they’re obviously not too fussy about the finer details of their immediate environment.   They’re pretty low key around people and don’t seem to mind suburbia.  I wonder how much they need the bushland I’m finding so sustaining in lock-down.

The sparrowhawk pair isn’t the only birds aware of the value of this bit of floristic real estate, though.  I’m pretty sure currawongs took some of the sparrowhawk’s nestlings in previous clutches, and I wonder whether the presence of these smart and social predators has kept the pair away for the last three years.  But yesterday a bit of argy-bargy with another of the locals – a family of kookaburras.  I’ve been seeing them around a bit more than usual this winter, surveying the scene from our dawn redwood and the remnants of our long-dead pine trees.

Yesterday I wandered up the drive to see if I could capture any trysts or DIY activity, and there was a cheeky kookaburra in the exact  spot I saw the sparrowhawk chilling in the day before.  And another, on a second favoured hunting perch, further up the tree.  The sparrowhawks were in the vicinity, but as soon as one landed in that pine, the kookas were after it.

Here’s a deeply discombobulated sparrowhawk, catching its breath a few metres away.  A minute later, the kookaburras were back and the pair of raptors hightailed it into the distance.

Sparrowhawk recouping after being chased by a kookaburra

I feel stupidly anxious about this, for some reason.  Every year about this time, we hear the sparrowhawks and I’m always hoping they’ll hang around and try to raise some chicks again.  For the last couple of seasons we’ve been disappointed.  But this year, silly as it seems, it feels a bit more high-stakes, and not just because we’re stuck at home with near-infinite opportunities for bird watching.  It feels symbolic even.  If this avian couple’s romance and nestbuilding comes to fruition, somehow it signifies that my little family will stay safe here too, safe and sane and together.  And if not… these things somehow seem less assured.

But of course, that’s a nonsense.  Birdwatcher magical thinking.  If the sparrowhawks find a better place to nest, and our trees get a different set of inhabitants, there’ll still be things to do, birds to listen out for, a different family to get to know.

Kookaburra family resemblances

The previous adventures of our local sparrowhawks

Sex, nests and dogfighting

Collared sparrowhawks vs Pacific bazas

Motherhood on a windy day – the sparrowhawk chick grows up

Death and sibling rivalry

Sparrowhawk summer

Battle of the baby birds

Welcome beautiful stranger

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January 26, 2018

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Backyard birds, Biodiversity, Brush turkeys, Climate change, Death, national parks, nesting, predation, raptors, Seasons

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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.

Clamorous reed warbler with nesting material
Male musk duck – a resident here
Moorhen family
The campsite at night
White faced heron hunting
One of many dragonflies

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.

One very hot white throated tree creeper
Eastern water dragon
Twerking wombat

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 order.  The 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.

Juvenile collared sparrowhawk with prey
Calling for the missing sibling

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.

Red wattlebird
Little wattlebird

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.

Eastern spinebill
Brown thornbill
Lewin’s honeyeater

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?

Spotted pardelote
New holland honeyeater

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