Hot property, water views

It’s been a good season for NSW’s floral emblem. The terrible fires of 2019-20 put some species of waratahs under threat.  Others, subject to fires of lesser intensity, have regrown from the massive underground lignotubers, up to half a tonne in weight, that allow them to regenerate after a burn.  2021 was the first year when botanists predicted a big flush of flowers – and it happened between August and October this year.  And people were out in the bush to appreciate them, thanks to the east coast lockdowns which meant that one of the few activities people could legally and safely do was bushwalk.  Appreciate them and sadly, steal them.  The floristry industry grows its own waratahs but last year so many flowers went missing thanks to visitors to national parks close to suburbia that rangers took to daubing the flowers with blue paint.  Around my way there is much proprietorial concern about the local waratahs.  Pictures of flowers and advice on walks to take to see them appeared on the local facebook group and there was much angst about stolen blooms.  If the flowers are picked, waratas don’t produce seedpods.  The high carb content of waratah seeds, making them a tasty snack for critters means its pretty unlikely they’ll find a spot so well hidden that they get a chance to grow anyway, but if the flower is sitting in a vase on someone’s sideboard, that’s certainly not going to happen.

The flowering season is over now, but waratahs are still hot property as far as the local birdlife is concerned.

Over the summer, I’ve been wandering regularly down to a nearby creek (perhaps rivulet is a better word) to spy on LBBs.  Under the twisted  limbs of the angophoras, the little birds frolic through waist-high shrubs, and nest in the stands of saplings along the creek edge.  It’s a little bit magical.  I’ve been lured along that path by a bold grey strike thrush, who hopped along in front of me the whole way; watched the variegated fairywren blokes get hassle from their female companions; been serenaded by golden whistlers and caught one of the ubiquitous new holland honeyeaters sipping nectar from a mountain devil.  Not to mention regular encounters with the local dragons.

Little waterdragon that hangs out on the rocks by the creek

Male variegated fairywren being sat on by females in his group

A particular spot where the path crosses the creek has been my go-to since late last year, when I spent an hour watching a parade of little birds quarrelling over bathing rights in the shallows.  It was so delightful I keep going back hoping for more.

Brown thornbill

So a couple of weeks ago, to stretch my legs after a day staring at screens, I headed down there.  I spotted the construction in the waratah bush right away.  A nest – exciting in itself, but there was movement.  A live one!

New Holland Honeyeater standing on a nest in a shrub and peeping at the photographer

New Holland honeyeater peeping at the photographer

New holland honeyeater sitting in a waratah bush

New holland honeyeater snug in a nest

This new holland honeyeater seemed so at home, rummaging around in the bottom of the nest, and then sitting in the classic “bird in a nest” position, I assumed I’d met the author of this structure.  But, apparently not.

Red browed finch arriving with nest building materials to find it is occupied by a honeyeater

I would love to hear the inner monologue of this red browed finch.

The finch took a pit stop in another branch of the waratah to recover itself.

Red browed finch with nesting material waits to eject the honeyeater in its nest.

Honeyeater in denial.

I was distracted by a passing dollarbird, and by the time I looked back things were looking very different.

Once the nest was reclaimed, the finch and its partner kept on with the nest building.

A few days later, I went back to check out this waterfront property after the builders were done.  No signs of the pair of finches.  Perhaps they were tucked up inside?  I hope they hadn’t miscalculated in picking this nest site, so close to a footpath.

What was this honeyeater interloper was up to?  While brood parasites like koels and channel billed cuckoos (obviously) lay eggs in other birds’ nests, to the best of my knowledge stealing a nest from another bird isn’t a common thing, at least amongst smaller birds – although, dear reader, I’d be happy to be corrected on this.  My favourite example of nest reuse (more accurately “protective nesting) is the story of various little birds – sparrows, swallows and starlings – finding spots to lay their eggs in the 3 metre pile of sticks that ospreys accumulate as they return to the same nest over the years. The raptors and their squatters seemed to breed happily side by side, with the insect eaters snaffling critters attracted to the rotting fish corpses in the osprey nest, using osprey feathers for nest lining and getting some protection from predators by cohabiting with great big raptors.

Nonetheless, even reusing your own nest from a previous season’s nest has some downsides.  They often get a bit nasty, hoaching with fleas and other ectoparasites.  Predators also get to know the location. Things are different when nest sites are hard to come by – hollows are often reused again and again – and there’s evidence of the same cliff side peregrine scrape in Tasmania being used for 13 thousand years.

If he wasn’t trying to steal the nest, perhaps the honeyeater was lost?? The red-browed finches’ nest at the time he popped by was a similar shape to the cupped nests that honeyeaters make.  They’re fidgety birds that look like they have a short attention span but it seems a little bit unlikely.

new holland honeyeater perched on a twig

More likely he dropped in to filch some nest materials, a habit lots of birds have.  Looking back at my pictures, it looks like he started out on the hunt for materials and then just settled in and got comfy.
I’ll be back to the creek to keep tabs on this waterfront hot property – from a respectful distance, of course.  The red splash of a waratah in spring is a rare treat but the red baby redbrowed finch or two would be a wonderful consolation prize.
red browed finch in profile
Birdwatching moments down the road from our Berowra backyard

When too much (raptor) sex is barely enough

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.

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

 

Loves and leaves

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.

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.

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.

 

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.

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

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.

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

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.

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.

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.

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.

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

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.

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).

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.

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.

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?

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.

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

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.

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.

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.

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.

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?

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.

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.

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.

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.

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

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

Into the matrix

Gerogone profile distance for crop wide

A busy day at the bullrushes by Terry’s Creek for this brown gerygone.  It really got into  a frenzy as it threw itself around trying to tug away the requisite materials for nestbuilding.

Although they’re quite common up and down the east coast from far north Queensland, down to Victoria, where they’re actually expanding their range, this is the only place I’ve seen gerygones.  Half-way through my daily commute along busy Epping Road in suburban Sydney, in line of scrubby woodland only a couple of hundred metres wide flanking a malodorous creek  in a valley awash with weeds.  But there’s plenty of cover, a water source, and the bushland stretches maybe three kilometres along the creek, all the way down to Lane Cove National Park.

Gerygones are the kind of little insectivorous bird that do okay in quite small patches of suburban reserve, but absolutely don’t make the leap, in the words of Patricia Hodgson and Richard Major “into the matrix”.  The urban matrix, that is.  Some of the other birds I see regularly at Terry’s Creek – the white browed scrubwren and the red-browed finch – are quite happy hanging out in the scungy waste ground next to railway lines or dank weedy gullies, but are less keen on suburbia.

For some reason, silver-eyes are an exception – they’ve taken the blue and the red pill.  You find them both in and out of the urban matrix in “almost any woodland habitat“.  This one and his gang blithely flew in to have a nibble on a riverside pittosporum as I stomped around only an armslength away.

Silver eye and flower squarer

Silvereye in pittosporum

Some of the other locals at Terry’s Creek do sometimes visit gardens and backyards, but not ours (sniff).  I’m pretty sure our “house birds”, the resident red and little wattlebirds, keep them away. This week I’ve seen the little wattlebirds have a go at putting the frighteners on some much heftier residents.

Satin bowerbird at drink with wattlebird good crop

Head to head between a male satin bowerbird and a little wattlebird

Satin bowerbird scaring off little wattlebird crop larger.jpg

And it’s on!

Kooka and wattlebird 2 crop and amend

Just before the wattlebird bit the kookaburra on the bum!

And we’ve worked out why the wattlebirds are so aggro this weather.  Only a couple of metres from our backdoor, at eye level, right beside the path to the chook run and the washing-line, there’s a nest in the middle of one of our banana trees.

If you made an extensive search around the yard to try to find a place more exposed to human influence you’d be hard pressed to find one.  Tobacco fumes constantly waft around the nest from the chain-smoker on the back verandah, and children run past shouting maybe ten times a day.  More often, now we’ve spotted the nest and the two brown speckled eggs inside it.

The incubating female has a genuinely terrible approach to camouflage.  Whenever human is nearby, popping into the laundry or watering the herb garden, she points her beak to the sky and stays very still.  She’s pretending to be a stick, I think.  A surprisingly bird shaped stick with a beady, watchful eye.

Wattlebird on nest in banana tree mid

Female wattlebird incubating eggs in our banana tree

Wattlebird tail and banana crop

The tail’s a bit of a give-away as well.

Initially I figured that the wattlebirds picked this impropitious spot to raise their young because they were, frankly, a bit dim.  But then I thought back to last year’s summer of the sparrowhawks – the sheer number of chicks I saw eviscerated and the dramatic drop in local wattlebirds population at that time.

Now, the collared sparrowhawks seem pretty laid back about humans, spending more energy guarding their nest from raids by currawongs and channel-billed cuckoos than worrying about our comings and goings. But even so, I’ve never seen them perching on the back step or checking out the laundry.  So maybe the wattlebirds aren’t so stupid. Perhaps they’ve figured its safer to raise your young around the slow-moving noisy bipedal predators than the airborne ambush-hunting ones.  They’re not just surviving in the matrix – they know how to hide there.

Sparrowhawk light on beak crop

Collared sparrowhawk on the look-out for prey

References

Woods, K.A. 1996 “Bird assemblages in a small public reserve and adjacent residential area at Wollongong, New South Wales” Wildlife Research 23 605-20

Hodgson, Patricia, French, Kristine and Major, Richard E. 2007 “Avian movement across abrupt ecological edges: differential responses to housing density in an urban matrix” Landscape and Urban Planning Vol 79 Issues 3-4, pp.266-272

 

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

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….