A day out at the pool with the kids

During most of spring we woke up every morning to the sound of sparrowhawks shagging.  But for the last couple of months the alarm clock has been the crack of a whip.

An eastern whipbird pair have been whiling away time in our garden, offering their distinctive antiphonal duet – the male first with his whipcrack, followed up by his mate with a “chu chu”.  But they’ve had an extra with them this year – a youngster, with a kind of squelchy call that reminds me a bit of the red-crowned toadlets that I’ve been hearing on the fire trails throughout this soggy soggy summer.

Recently fledged juvenile whipbird

The whipbirds have some interesting child-rearing habits, according to researchers Amy Rogers and Raoul Mulder.  They usually lay a couple of eggs.  Once the chicks fledge, the parents divide the task of looking after the kids quite formally between them.  Each parent looks after one of the fledglings exclusively.  You can imagine the therapy bills .  There’s an exception – if only one chick survives, then it’s mum who’s in charge.  So I guess it’s maternal care we’ve seen as we’ve watched the adult and juvenile slipping in and out of sight around the garden.  There’s definitely a whip-cracking male around, but all thee have only been spotted together in the garden once – and I wasn’t there with my camera to catch it, so I question if it ever really happened.

Whipbird chicks spend about six weeks with their parents after fledging, sometimes even hanging around until the next season, and it’s been interesting watching the adult and its offspring interacting, as the young one slowly morphs from its slighty fluffy, brown “I just came out of the nest” look to something more like an adult appearance.

Adult whipbird with a juvenile following it

I think one reason the whipbirds make such regular appearances in our yard is the frightful mess it’s in.  We’re not path sweepers or lawn groomers.  More stick-pilers, fungus-harbourers and ignorers-of-organic-detritus.  My efforts to promote biodiversity are not solely confined to a failure to rake, however.  I’ve sunk the value of at least one of the kids’ kidneys into shrubs, vines and groundcovers, some of which have survived.  While I have regularly seen the whipbirds in our kiwifruit arbor and the youngster has been spotted leaping about in a demented way amongst the ferns and vines outside our kitchen window, the native violets, which are threatening to overrun the house during this wettest summer in 30 years, seem to be a favoured spot.

Here we see chick watching mum head down bum up in the viola hederacea (you can just see the tail in the lower half of the first picture).  Next it’s little one that has its butt in the air, retrieving something invisible but presumably tasty.

Juvenile whipbird watching adult hunting for food

 

Despite their furtive habits and preference for the undergrowth, it turns out whipbirds can be pretty assertive under the right circumstances.  I was impressed by the use of eye contact in a  show-down with one of our many resident brush turkeys over a bird bath.

Eastern whipbird and brush turkey eye to eye

Showdown at the bird bath

The best time to spot two generations of whipbirds is around lunchtime, at the birdbath.  Mum arrives first, has a wash and then a bit of a groom, perched above on some wonga wonga vines.

Whipbird mum having a wash

Having a splash

If the coast is clear, the youngster appears.

Juvenile whipbird perched on a bird bath

Juvenile whipbird taking its turn in the birdbath

Juvenile whipbird and mum nose to nose 2 crop amended small

Juvenile whipbird and mum beak to beak

Awwwwww.

Having watched this scene of filial affection unfolding around the birdbath at home, I was quite delighted to catch what I thought were some similarly touching moments at a pool in a more natural setting.

Brown thornbill in a banksia serrata

Brown thornbill in a banksia serrata

Eastern yellow robin

Spinebill feeding from a banksia serrata

Grey fantail - perhaps a young 'un with a bit of brown on the breast

Grey fantail – perhaps a young ‘un with a bit of brown on the breast

Lewin’s honeyeater in a banksia serrata

Juvenile spinebill hanging

As a devoted parent, I’m always happy to drive my kids to music lessons… especially if the music teacher’s home happens to be right next to a national park.  On a sunny late afternoon during one of these high-speed twitching sessions, I spotted some action high up in a Sydney red gum.

A hollow on top of a horizonal branch seemed to have formed a natural pool which was evidently a magnet for the local birdlife.

Two juvenile spinebills near the natural pool in the angophora tree

Two juvenile spinebills near the natural pool in the angophora tree

Juvenile spinebills playing, fighting or perhaps play fighting

Juvenile spinebills playing, fighting or perhaps play fighting

I could see that there were some juvenile spinebills about, and some adults too.  Squinting through my lens I wasn’t quite sure what kind of pool side action was going on up there in the canopy.  Perhaps adults giving a tour to youngsters of all the best places to drink and bathe in their forest home? Showing them the ropes in this lofty aquatic environment – explaining the avian equivalent to those “no petting” “no bombing” rules perhaps?

When I got home and had a good look at the photos I found out otherwise.

Adult whipbird shirtfronting a juvenile by the angophora pool

Adult whipbird shirtfronting a juvenile by the angophora pool

Adult spinebill after a celebratory bathe

Adult spinebill after a celebratory bathe in the treetop pool

These poolside antics give “competitive dad” a whole new meaning.

Apparently, spinebills can have up to 5 clutches of eggs each year – almost as soon as one clutch are fledged, the parents start making a new nest ready, driving the older juveniles away.  And no free pass for the pool it seems!

Much as I love the gorgeous spinebills, for human Sydneysiders with our eyewatering real estate market and clutches of offspring near at hand, somehow the parenting style of the whipbirds feels closer to home.

Adult male eastern spinebill in a hibiscus tree

Adult male eastern spinebill in a hibiscus tree

More birds in our backyard

Cracking the whip in a messy yard

Blood feud in the dawn redwood

Death and sibling rivalry

Growing up is hard to swallow

Blue eyes and biteys

 

References

K. A. Wood (1996) “Bird Assemblages in a Small Public Reserve and Adjacent Residential Area at Wollongong, New South Wales Wildlife Research, 23, 605-20

Amy Rogers and Raoul Mulder (1996) “Breeding ecology and social behaviour of an antiphonal duetter, the eastern whipbird” Wildlife Research, 1996,23, 605-20

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

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 violaceusAnimal 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

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

Growing up is hard to swallow

It’s all about the young koels in our yard at the moment.  We have at least two of them hanging around the back yard, begging for food and slowly destroying the mental health of their red wattlebird adoptive parents.  Well, I hope for their sake there are more than one set of parents doing the provisioning.

While I’m still hearing koels begging endlessly, I have a suspicion that the parents are trying to  back off from supplying food. As a parent of teenagers I can certainly empathise.  Wattlebirds normally feed fledgelings for two or three weeks after leaving the nest.  The soundscape of our yard started to be dominated by the pleas of the koel youngsters around mid-January, so I think the parents’ patience is starting to wear pretty thin. I’m pretty sure that the koels are trying to push that envelope though.

I watched this rather grown-up looking chick sitting on a branch to beg relentlessly for at least half an hour without attention.  It whined and shuffled, whined and groomed.

It seemed to despair of getting any attention at one point and started rummaging around for its own tucker.   Clearly this flaccid flower didn’t cut the mustard.

Eventually the relentless moaning did result in a couple of snacks.

While waiting …. and waiting, and waiting… (I was almost as impatient as the koel for this fledgeling to get a feed…) I spotted a second youngster lurking nearby.  It looked a bit skinnier and its plumage a bit patchier and at first I wondered if it was a younger chick, hogging the attention of the exhausted parents.  But usually female koels only lays a single egg in a nest – which make sense since the chick heaves competitor eggs and hatchlings out.  Sometimes, it seems, koel females will return to lay an egg in a sequence of different nests so perhaps this second youngster was being fed by a different harried parent.  I feel kind of relieved on their behalf.

One way or another, all that whining seems to be getting less of a response this weather.  So our backyard koel chicks are having to forage for their own food. This nugget looks kind of unappealing, though perhaps no worse than the spider that I saw mum or dad retrieving a couple of weeks ago.

Our neighbour’s bangalow palm seems to be a favourite foraging ground.

Perhaps the temptations of the palms are a bit too great.  Last week, I watched a youngster beg from a branch near our back verandah for a while.  No parental attention was forthcoming, and I thought it had given up, as it went surprisingly silent for quite some time, hunching and looking pensive.  Then this happened:

I think this mysterious fruit must have been stashed in the bird’s crop, .  Certainly this same koel was stacking away the berries at an extraordinary rate on its visit to the bangalow palm, so the idea that it was tucking it away for a later snack seems pretty plausible.  Having read a bit about the way birds use crops – a muscular pouch in the oesophagus that stores food – I am now tremendously jealous.  What a terrific idea!  Why the hell don’t humans have one?  I suppose blokes can use beards, although that’s a visually disturbing alternative.

Koels – noisy, whiny parasites – get a bit of a bad rap around here, but I can’t help admire them – their chutzpah, their gorgeous feathers, and their admirable capacity to never, it seems, go hungry.

 

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

An ice storm, a flood and eight invisible fish: the fraught tale of a frog pond

hailstones in hand crop long

Water features have everywhere in Berowra this last year.  With half the suburb’s roofs smashed to bits by golfball sized hailstones just before Christmas, an ice-storm followed an hour or so later by torrential rain, lots of those water features were indoors and distinctly unwelcome.  In a suburb that has come to be known over the months of waiting for insurers to come to the party, as “Tarpaulin Heights” we got off relatively lightly, with our indoor water feature making only a cameo one-time appearance.

Inundation was the origin of our new outdoor water feature as well.  Thanks to topography and a inexplicably ruptured stormwater drain – I did fear at one time it was an inexplicably ruptured sewer, so I’m thankful for small mercies – when the rain comes down in Berowra, most of it seems to come through our backyard.

The weather pattern in Australia now, even here on the coastal fringe where the trees are still alive and there is grass, which is sometimes even green, seems to be long dry months punctuated by occasional periods of quasi-apocalyptic rainfall.  So catching some of the run off and making some use of it seemed like a good idea.  And then there’s my fantasies about frogs.

So in December last year, I dug a big hole, downhill from the stormwater drain and uphill from my veggie garden.  Deep holes are not easy to dig on Hawkesbury sandstone.  I was aiming for a depth of no more than 30cm, since I really didn’t want to have to fence my pond, but even 30 cm was a push. I rationalised the shallowness of the hole with reference to the gently sloping edges that would allow the amphibians of my dreams to rest comfortably on the edge of the pond.  Not a very convincing excuse to avoid further shovel work.

releasing fish

I lined the hole with a few centimetres of sand from the local garden centre.  Carpet underlay is sometimes recommended for a layer underneath pond liner but I went an old trampoline mat, since that’s the kind of thing I have lying around in my shed.  Retrospectively I’m not sure that was a great idea.  On top of that I put down rubber pond liner – quite a lot more expensive than vinyl, but not plastic and, in a household full of underused bikes, I figured, quite patchable.  In theory.  Underneath that footlingly small pond is six square metres of heavy duty rubber.

lily leaves late Jan

Nymphoides montana. I think.

Sensible guides to pond making recommend that you set up your fountains and filters properly, then add native plants, give it a week or so and then add fish.   However, a couple of days after setting up the pond with a solar powered aerator, native grasses (Carex fascularis and Schoenoplectus Mucronatus) and pond plants (Marsilea mutica, and if memory serves, Nymphoides montana) I spotted a huge number of wrigglers frisking gaily around their new habitat, and decided we would need to go fish shopping.

Our neighbours had demonstrated their true commitment to biodiversity by not just accepting but actively welcoming the idea of frog mating calls 24-7 outside their bedroom windows.  However, we thought adding a vast number of mosquitoes to the local ecosystem might not necessarily go do down equally well.  We decided to buy two pairs of pacific blue eyes to populate our pond, while we waited for other insect eaters – frogs and dragonfly larvae and the like – to arrive.

Pacific blue eyes are small fish – less than 8 cm in length and usually much smaller – that are keen mozzie eaters but not big enough to devour frog spawn.  They’re locals all up and down the East Coast, inhabiting both fresh waters and estuaries, so not too fussy about water quality.  Our local aquarium shop had a stock of them, though the staff were pretty clueless about which fish were native and which were not, offering us white cloud minnows (originating in China) as a possible alternative.  We took our two pairs of tiny, quasi transparent fish home and Ms 12 and good friend and frog lover from next door carefully introduced them to the pond, taking time to equalise the temperature of the water to minimise shock.

Fish introduction 2 before flood crop

All that happened around midday on December 20, the day of the hail storm and subsequent torrential downpour.  Within hours of settling our blue eyes carefully into our little pond, our backyard looked like this:

Ms 12 was desperately trying to block the exit from the pond, but I think realistically the Pacific blue eyes were halfway to Berowra Creek by this point.  There was much weeping and gnashing off teeth, counterbalanced, on my part at least, by a certain smugness that I hadn’t bought white cloud minnows or gambezi fish or something else that you wouldn’t want to end up in your local waterway.

Of course, what with the water being murky and the fish being small, shy and in essence invisible, we weren’t quite sure if we still had pacific blue eyes or not. Rather than waiting for the mosquito murmuration that would tell us that we didn’t, and with an eye to diminishing the level of weeping, we went back to the aquarium shop for yet another couple of pairs.

That was a nearly a year ago now, and there have been no further sightings of the fish.  The solar powered bubbler carked it in another downpour, along with the rainbow nardoo which I accidentally ripped out while clearing out excess algae during winter months.   But the wriggler count has stayed low and the pond has done pretty well as a habitat.  Not to mention the fabulous opportunity it’s given me to buy new plants (full list at the bottom of the blog)

On the down-side, I’ve been surprised how often I have to top the pond up with water.  Either it has a surprisingly high level of evaporation for a pond in shade much of the day or the logs and rocks I dragged around the yard to make a naturalistic edging have punctured the rubber lining in some mysterious but annoying way.  Perhaps there’s a reason people don’t recommend using old trampoline mats underneath your pond.

One way or another, I have become a pond slave.  I’m constantly ruminating on where I’m going to get my next hit of  non-chlorinated water. The many many hail-holes in our gutters all have a bucket underneath them and I usually have a bucket of tap water off-gassing somewhere around the yard. I have heard rumours there may be better ways of collecting rainwater than this.  Working on it.

Blue banded bee in flight cropped

Blue banded bee on Artenema fimbriatum (koala bells)

It was lovely to see the blue banded bees the visiting koala bells and dragonflies hovering over the water, but we’ve had to be patient with the frogs. The approach you take to getting a frog is a bit like the approach 1950s women had to take to getting a boyfriend – make yourself appealing and wait.  Chytrid fungus is devastating frog populations across the world and if you go and collect frogspawn or tadpoles you can help it spread.  So we waited.

Skinks by the pond closeup

A few months back I heard the distinctive pock of a striped marsh frog in amongst the waterside foliage. I was beside myself with excitement, but after I let the chooks out to freerange for the afternoon, the marshie disappeared.  Troubling. It seemed like having both chickens and frogs might be an impossible dream.

Apricot by the pond 2 crop

Apricot nibbling at the microlaena stipodes lawn.  And possibly frogs.

But by the end of winter, another striped marsh frog was in situ, vamping the local females with the alluring noise of a loudly dripping tap.  Perhaps this male was too large to be wolfed down by the chooks on their visits to the pond for a drink and an insect snack.

And, glory be, last week we spotted a couple of handfuls of tadpoles, huddling at the bottom of the pond near some algae.  I am now officially a frog mumma, as my daughter said.  But I’m not feeling too much eco-smugness.  According to the Australian Museum, the striped marsh frog is an unfussy beast – it likes a pond but even a polluted ditch will do.  Apparently they’ve been found breeding in dog’s drinking bowls.

So no pressure.  The bar has been set low for us as aspiring frog parents. Let’s see how low we can limbo.

Pond in Nov 19

Native plants in and around our pond.

Artenema fimbriatum (koala bells) – blue or pink flowers in summer.

Bacopa monnieri (Brahmi, memory herb) – small white flowers.  Grows in and near water – edible plant.

Carex fascularis (tassel sedge).  Grows in moist to wet soils in part shade, up to a metre high.

Centella asiatica (Gotu kola, pennywort).  Edible plant.  Grows in part shade in moist soils.

Cissus Antarctica (kangaroo vine)    Planted in the drier area around the pond.

Doodia aspera (prickly rasp fern).  Grows in moist areas, nice pink new growth.

Finicia nodosa

Hibbertia scandens (guinea flower)   Flowers in shade,

Isolepsis cernua (Live wire) – low growing grass with interesting bright seed heads.

Juncus flavidus (billabong rush)

Libertia paniculata – in moist areas near pond in shade, alongside ferns. White flowers in early spring.

Lythrum salicaria (purple loosestrife)- growing in drier areas near pond.  Dark purple flowers in autumn.  Dies down in winter.

Marsilea mutica (rainbow nardoo) – pond plant.  Beautiful patterned leaves.

Microlaena stipoides (weeping grass) – grass surrounding pond.  Grows well in shade in damp or dry conditions.

Mazus pumlio (swamp mazus) – grows in moist soil.  White flowers in autumn.

Nymphoides montana – pond plant with beautiful yellow flowers.

Peperomia (native) – native succulent that grows well in shade.

Poa labillardiere (tussock grass) – grown in drier areas around the pond

Schoenoplectus Mucronatus – rush growing in the pond.  Interesting spiky seed pods.

Tetragonia tetragonoides (warrigal greens) – edible plant. Grows very well in damp or dry soil in part shade. Delicious to humans and also chickens.

Tripladeua cunninghamii (bush lily) – grows well in part shade, pink flowers in spring. I  killed it.

Dragonfly dark later

Murder, imprisonment and native grasses

This blog starts and ends calmly and peaceful as we consider lush grass growing.  In the middle there’s some horrifying interspecies violence – I’ll tell you before it happens so you can look away if you need to.

When we first into our place nearly a decade ago, there was plenty of grass in the backyard.  Note, I don’t say lawn.  Which is fine by me, since an array of weeds offer much better nutritional resources for chickens than a monocultural sward.

So a sequence of domestic fowl have enjoyed the delicious mix of trad, ehrharta, buffalo grass, couch, and a plethora of other greens as a supplement to their laying mash and scratch mix.   The trad went first.  Chickens absolutely love this horrid weed and have scratched out every shred, producing the fabulously golden yolk that are a definitive feature of your happy free-range egg. For a while the other grasses held on, but, over a few dry winters, as our flock grew to six chooks and an apparently infinite number of semi-resident brush turkeys, the greenery eventually lost the fight.

Sequence of brush turkeys crop

Peak brush turkey

Perhaps not surprisingly, I don’t have a lot of pictures of the muddy home farm during this “trench warfare” period.  And I have absolutely no pictures of the traumatic events that followed.  It’s taken me nearly a year to get up the gumption to write about it.

Baby brush turkey astonished

Very cute baby brush turkey hanging out with our chicks a couple of years back

Until November last year, the many brush turkeys hanging around the backyard were an annoyance but nothing more: scratching up seedlings, stealing eggs and making free with the chickens’ dinner.  The baby brush turkeys liked to huddle up to our newly hatched little chicks.  The older turkeys also seemed to like hanging out with the flock but were easily spooked by them.  It only took boss chook Treasure giving a funny look to have the brush turkeys scatter or even flap away. But that all changed last spring.

A large male brush turkey started hanging around, pursuing and doing his best to mount the chickens.  One day we noticed that several of the girls’ combs were bloodied, and concluded it was the work of this nasty animal. The neighbours had spotted the sex predator too. There were rumours of pet birds being attacked all up and down the street.

Concerned, we decided to keep the girls in Colditz, the steel-framed predator-proof cage for a day or two, rather than letting them roam the yard as usual.  The next day I was working from home, and by the afternoon, seeing no signs of the turkey and feeling sorry for the poor chooks pacing up and down in their constrained night quarters, like Steve McQueen in the Great Escape, I decided to let them out for a few hours.  I went back to my computer.

If you are easily upset, now is the time to look away.

Brush turkey wattle closeup.jpg

Male brush turkey extreme closeup

Late that afternoon I heard a pitiful squawking and rushing down to the yard.  All of the chooks were bleeding copiously from their scalps and two of our poor girls were mortally wounded, with huge slashes through their backs and terrible gouges to their heads.  Then we heard pitiful sounds from the last of our neighbour’s free-range chooks.  We jumped across the fence to rescue it, but too late – its eye had been pecked out. All three birds died soon after.

Needless to say I was inconsolable.

The only way I could atone my guilt was to make the surviving chickens a safe place to stay.  So that Saturday, in a frenzy, I pulled together an implausible collection of wire, wood from futon bases, half an aviary, parts of a picket fence, innumerable pieces of bamboo and that old standby, trampoline netting, to make a 8 square metre covered run adjacent to Colditz. The run featured Palm Beach as an elevated hangout zone and egg laying area, perches at a range of heights and diameters and its own personal orange tree.

The chooks were safe, and over the next few weeks slowly recovered from their head wounds.  But they weren’t happy.

So over the festive season, I had another crack, making an extension the same size again, which admittedly did involved purchasing a couple of steel droppers and a box of screws.  Otherwise, I was extraordinarily pleased I was able to make the “outdoor room” entirely from rubbish I scrounged from the side of the road.

Chook run extension

The outdoor room, featuring cot railing and an indoor clothes hanger feeding hatch

Now the chooks were secure in their generous run, an unworthy thought came to me.  The scorched earth of the backyard, without a single blade of grass and denuded of  every remaining seed, was now perfectly prepared for something I’d long aspired to have – a backyard full of native grass. The kids had started expressing a longing for a little bit of soft lawn to walk on, and I was keen to take on the challenge.  Buffalo, kikuyu and ehrharta outcompete native grasses, but thanks to the chooks, I doubted there was a single weed seed left on the premises.

It was time.

I decided to mostly use microlaena stipoides, weeping grass, a fine bladed grass that tolerates shade and enriched soils and, once established, copes with minimal watering.  I ordered a couple of hundred grams of a hybrid microlaena called Griffin weeping grass, a low growing variety bred by the Department of Botany at the University of New England.

My first sowing was in early summer – the best time for this variety – warm enough for a speedy germination and not so hot it’s impossible to keep the seed bed moist.  I raked in the seeds – they shouldn’t be buried more than 1 and a half centimetres deep – and covered them with the veggie nets that I usually use to protect seedlings from bowerbirds, chickens and possums that aren’t trying too hard.

The Great Berowra Storm of Christmas 2018 treated us relatively kindly ( two broken skylights is a pretty good outcome from golf ball sized hail) but did significantly undermine my efforts to even distribute those rather expensive grass  seeds.  But I guess the torrent saved me watering for a few days, as well as reminding me why we needed grasses and their root systems to stop our topsoil flowing away on those occasions when our yard becomes a tributary to Berowra Creek.  On hot days when we didn’t experience a climatic apocalypse, I did get out the hose for the first month or two – microlaena needs to be kept moist until its root system is sorted.

In the light of its inpropitious beginnings, the microlaena has done pretty well, coping with the chooks snacking on it a couple of days a week.  That brutish brush turkey has never returned (I suspect foul play given his cruel behaviour to most of the hens in the street) but we like to let them roam when we can keep an eye on them.  And the native grass has remained beautifully green through yet another very dry winter.  In the picture above, alongside the weeping grass, you can see my low-skill terracing with fallen wood and another native grass, poa labillardiere. The aim is to redirect any storm water into our new pond (more on that another day)

So after two days of drenching rain,  I decided this afternoon to sow another packet of griffin weeping grass, filling the gaps scoured by last December’s floods.  Yet more trampoline netting has been hauled out of the shed to protect the newly spread seed from the chooks on their weekend perambulations.

Even if I’m slightly nervous of what they might do to my baby grasses, I’m grateful to our girls.  Without their commitment to scratching and salad, we would never have got this far, and certainly not without reaching for roundup or something equally scary.   I hope I can return the favour by keeping them safe (if not always happy) and feeding them plenty of greens.

Microlaena and stepping stones

More stories of life, death and gardening from our backyard

Night of the living mulch: cover crops for the zombie apocalypse

Andy Ninja’s great escape

Chicken TV: the make-over show

DIY by subtraction: the kiwifruit arbor

The phantom egg eater: caught in the act

The singing and the sea

Bute with shiny landscape tidiedWhen you put your boat in at Cowan Creek, you know you’re paddling in the sea.  Yes, there are rocky slopes on every side, and eucalypts and banksias lean over the shoreline.  The rows of hot pink bells of epacris longifolia dangle amazingly close to the waves.

But look over the side of your boat, especially in this big dry, and your gaze falls metres deep into into the crystal clear green water.  It might be called a “creek” but there’s no murky river water here.  Further downstream, where Cowan Creek meets the Hawkesbury proper at Broken Bay, the Pacific meets the horizon and you really know you are in the ocean.

Fishing boat and west head little boy

Fishermen off Flint and Steel Point

Cormorant with fish

Cormorant off Juno Point having a snack

But far above the official mouth of the river – the limit of “flat water sailing” drawn between Juno Head and Flint and Steel Bay – the water is briny.  The tide rolls up the Hawkesbury as far as the Grose River Valley, 138 kilometres from the sea, taking a wedge of salty water upstream.  If Broken Bay, where these pictures were taken, is essentially a marine environment, Cowan Creek is not too much different.

Pixellated yachts

Yachts off Cottage Point

Because of course, the Hawkesbury is a drowned river valley.   The river channel that once wound its way twenty five kilometres to the east, across the continent shelf, has long ago disappeared two hundred metres or more beneath the ocean.  The late Quaternary Marine Transgression that drowned the Hawkesbury started 18,000 years ago and went on for 10,000 years, with the water level peaking just a metre or two above current sea levels.

Paul Boon, in his fascinating history of the Hawkesbury, reports that during that time, sea level rose at perhaps 8-10 metres every millennium, at some times as 40 metres in a thousand years (Boon, 2017, Chapter 3). It‘s hard to imagine what that must have been like for the first people here, the Guringai and Dharug people, moving again and again ahead of the rising tide, away from the coastal flat lands to the hills of the Hornsby plateau.

Side illuminated trees for crop

On the way to Stingray Bay

Even more mindboggling to think, as Boon quietly points out, that over the last few decades sea level has been creeping up by around three millimetres a year. If the CSIRO scientists are right, and I for one don’t doubt they are, sea levels are changing as worryingly fast, if not as fast as the speediest rises in the Flandrian Transgression. On the bright side if I live long enough, there’ll be far more of the upper reaches of Cowan Creek to explore, in an admittedly sweaty and decrepit manner, in my kayak

Pink cloud and cowan creek

Sunrise sky near Cotton Tree Bay

Last weekend’s paddle reminded me of what a special place the Hawkesbury is, a drowned river valley where, after rain, waterfalls tumble off the sandstone straight into the sea.  I was coming back from a jaunt to Smith’s Creek when, heading into a bay to avoid a plague of water skiiers, I heard a lyrebird going for broke.

According to Birdlife Australia, superb lyrebirds are inhabitants of moist forests. I’m sure the one I heard scratching around in the undergrowth by the shore, would soon be heading back to the gullies and the treetops.  But in its distant melange of calls – of satin bowerbirds, kookaburras, currawongs, red wattlebirds and other things I just can’t recognise – was a sound I’d never heard a lyrebird make before.  I’m sure I heard an impression of that paradigmatic bird of the beach – the silver gull.

And that’s the soundtrack of the Hawkesbury estuary, right there,

 

What are your bird call spotting skills like, dear reader?  Can you recognise any other shore birds in this estuarine lyrebird’s song?  If you can spot any extra calls, please let me know!

Other stories from Cowan Creek and thereabouts

A glimpse of a peregrine falcon hunting: death and good fortune in Cowan Creek

Old hands: how Smith’s Creek was nearly Canberra

Stingray Bay – lost and found

The Hawkesbury in winter: the shortest days and how to use them

Broken Bay at low ebb: the troubled history of Hawkesbury oysters

Around the point 2

A winter morning in Cowan Creek

The one-eyed butcherbird

Butcherbird in tree good eye gleaming 2

We had an unusual visitor this weekend – a cocky grey butcherbird, turning up first in the branches of the Japanese maple that reaches up to our back deck, and then hopping boldly onto the balustrade.

BB profile horizon corrected cropped

Our butcherbird showing off his hooked beak

Butcherbirds are just the kind of generalists – like fellow “corvoids”, magpies and currawongs – that do really well in urban areas.  But we’re rarely had them turn up at our place before.

And this lovely lad (or lass – they look too similar for an amateur like me to distinguish) was notable in another way, too – it had only one fully functioning eye.

Looking side on you could see a glimmer of a right eyeball, but it was sunk back into the feathers of the head – on a front view only his inquiring left eye was visible.

Butcherbird on ground looking at me frontallycrop

Our one-eyed butcherbird

The wounded eye seemed to have healed long ago – this guy was distinctly perky and healthy looking, if a little edgy.  And this was an adult bird – no sign of the brown and buff colours of a juvenile (like this one spotted at Narrabeen Lake a few years ago).  So whether it had been injured as a chick or as an adult, it seems to have been getting along okay for quite some time.

Juvenile grey butcherbird crop long

Juvenile grey butcherbird

In the past, animal rescue organisations assumed that birds with serious injuries to an eye wouldn’t make it if they were released from captivity.  Usually birds found wounded in this way were euthanised.  But in Germany and the US, researchers and birdwatchers have reported hunting birds like owls and eagles surviving for years in the wild – and even successfully breeding and raising chicks – with only one functional eye.

On a first glance, it seems obvious that binocular vision would be important for judging distances when flying.  An early twentieth century ornithologist proposed that “a bird is a wing guided by an eye” but it seems there’s a lot more to eyesight in birds than navigating through the air.

Researchers think that binocular vision is more about being able to see what you’re doing with your beak than getting around on the wing. Birds that have to do tricky things with their bills – cormorants making sure the fins of the fish they’ve just caught are in the right position to slide nicely down their throats, for instance – need to see what they’re doing.  Having your eyes at the front of your head means you’re less likely to spot a predator from behind, but it’s worth it for the tucker.

It was interesting to watch our visitor managing life with a limited visual field.  He could certainly fly, and RB saw him successfully catch something that was scuttling around on the deck.  That said, when we (naughtily) fed him a few pieces of meat, he seemed to struggle a little to get a handle on it.

He was also pretty twitchy, reacting to every sound, looking regularly over his shoulder so he could keep tabs on his surroundings with his good left eye.  Butcherbirds usually dive down on prey from above, and as he looked out for tasty treats below, he kept his head cocked to maximise his vision.  As a someone with only one “good” ear, I recognise the advantages of that head tilt!

Butcherbird facial closeup good

Our one-eyed bird keeping an tabs on surroundings with his one good eye

Our visitor also seemed to understand the possibilities of humans as a resource.  At one point he flew right up to where I was sitting by the balustrade, looked me in the face and “spoke” to me in a mildly demanding way familiar to me from my teenaged childen.  Later on, I went inside, leaving the sliding door was open, just a bit. The butcherbird hopped up to the door,  and after a few moments of hesitation, continued straight through into the house.

Butcherbirds are smart and excellent problem solvers.  They’re also creative, as my colleague, the violinist and composer Hollis Taylor found, when she started analysing their marvellous improvisational music making.  Was our butcherbird visitor just curious, and yearning to see our interior decor?  No matter how clever these guys are, that seems unlikely.

Butcherbird on chair looking at me blind eye visible crop tighter.jpg

I suspect that this guy was looking for friends.  Perhaps some local folks who regularly fed him – maybe in a room with a sliding door, just off a deck?  Did his human buddies take care of him after his eye was injured?  I don’t know but I can say for sure he expected good things from us, and our kind.

BB inside head cocked cropped

Grey butcherbird expecting good things from humans

References

Brown, Matthews (2016) Clever crows: Investigating behaviour and learning in wild
Torresian crows (Corvus orru) and related Cracticids in a suburban environment, Doctoral thesis, Griffith University.

Hegemann, A, Hegemann, ED, Krone, O. (2007) “Successful rehabilitation and release with subsequently brood of a one-eyed Eagle Owl (Bubo bubo)” Berliner und Münchener tierärztliche Wochenschrift 120(5-6):1

Martin, Graham (2017) “What drives bird vision? Bill control and predator detection overshadow flight” Frontiers in Neuroscience 11

Tyrrell,Luke and Fernandez-Jericic, Esteban (2017) “Avian binocular vision: It’s not just about what birds can see, its also about what they can’t” PLOS One, Mar 29.