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.

 

Cracking the whip in a messy garden

Typical whipbird picture crop tighter

This is a fairly typical photo of an eastern whipbird.  Thanks to its cracking call, you know with absolute certainty that the bugger’s there somewhere, darting from bug to evasive bug.  But up until recently all of my pics of them were abstract impressionist in style – an suspicion of a smear in the undergrowth.

Which is a pity, because even aside from their excellent call, these are fine looking birds.  I am a fool for anything with a crest, no matter how run of the mill.

But my days of cursing invisible whipbirds are officially over.  Because we now have a  resident pair in our the garden.

My efforts at growing food in surburbia, or at least food for human consumption, have been largely in vain.  Every now and then we get a few bananas or kiwifruit, tamarillos or jerusalem artichokes before the local possums, bowerbirds, cockies, bats and rats figure out they make good eating.

If I have singularly failed to feed us, I have been fairly successful in turning the garden into a tangled mess riddled with trip hazards.  In other words, top drawer whipbird habitat.

And now they’re here, there’s a decent chance they’ll stay.  Whipbird pairs are territorial, usually nesting each year within a few metres of last year’s spot.  And it seems after their chicks are raised, they stick around.

I’ve certainly seen our pair doing their best to defend their territory by seeing off the impudent rivals they spotted in the mirror in the bottom of the garden. Judging from the time they spend singing into it, that mirror has had far more impact on the whipbirds than the horde of male brush turkeys it was intended to discombobulate.

Whipbird midbath calling clear crop long

Eastern whipbird having a lovely sing in the bath

Something I didn’t realise until recently is that the distinctive call of the whipbird is an “antiphonal duet”, just like the call of the koels (or “those bloody koels!” as they are known locally).  The male of the pair produces the whipcrack, followed seamlessly by a “chew chew!” from its female partner.  This kind of singing is usually done by established pairs.

Tactful ornithologists describe whipbirds as “socially monogamous” (a bit like National Party MPs?).  Whipbird researcher Amy Rogers comments that, in general, duetting birds like these have “very low divorce rates” compared to non-duetting birds (Rogers 2004 433).

Juvenile koel calling long

A juvenile bloody koel

Having spent years crouched in the undergrowth surreptitiously observing the sex lives of South Australian whipbirds, Rogers has has concluded that duetting is “acoustic mate guarding” – a way for females to keep close tabs on their other half. In the nests she tracked, twice as many female birds were born as males.  Consequently spots with attractively tangled undergrowth were awash with unattached lady whipbirds seeking a mate and territory.

Whipbirds blokes seem to be a good catch, fetching plenty of food for nestlings, even if they don’t help incubate eggs.  After the youngsters leave the nest, each parent exclusively feeds just one of the fledglings. You can only imagine young whipbirds end up spending a fortune in therapy.

So once a female has hooked up with a male and they’ve nabbed some decent territory, she keep tabs on him by finishing his sentences, as it were.

Female whipbird in vine

I reckon our place, with its undisciplined shrubbery, snake-friendly piles of sticks and vines that loop their way through the trees at perfect garotting height would be damn desirable breeding grounds. I’ve certainly seen the whipbirds gleefully leaping around our carport picking off the window spiders (3/5 for toxicity in the “deadly critters of Australia” book I gave my Scottish spouse to help him settle in when he first arrived).

It may be cockroach infested deathtrap but the whipbirds and the lizards seem to like it here.  I’m not complaining either.

Skink with giant cockroach crop

You’ve got to admire the ambition

References

Frith, C.B. (1992) “Eastern whipbird psophodes Olivaceus listens to fruits for insect prey” Sunbird 22 (2)

Guppy, Michael, Guppy, Sarah, Marchant, Richard, Priddel, David, Carlile, Nicholas and Fullagar, Peter (2017) “Nest predation of woodland birds in south-east Australia: importance of unexpected predators” Emu- Austral Ornithology Vol 117 Issue 1

Mennill, Daniel and Rogers, Amy (2006) “Whip It Good! Geographic Consistency in Male Songs and Variability in Female Songs of the Duetting Eastern Whipbird Psophodes olivaceus” Journal of Avian Biology, Vol. 37, No. 1 (Jan., 2006), pp. 93-100

Rogers, Amy C. and Mulder, Raoul A. (2004) “Breeding ecology and social behaviour of an antiphonal duetter, the eastern whipbird” Australian Journal of Zoology Vol 52 Issue 4 417-435

Rogers, Amy, Langmore, Naomi and Muldera, Raoul (2007)  “Function of pair duets in the eastern whipbird: cooperative defense or sexual conflict?” Behavioural Ecology Volume 18, Issue 1, Pages 182–188

Toon, Alicia, Joseph, Leo and Burbridge, Alan H (2013) “Genetic analysis of the Australian whipbirds and wedgebills illuminates the evolution of their plumage and vocal diversity” Emu – Austral Ornithology Vol 113 Issue 4

More birds to be found in our backyard

A family of collared sparrowhawks – bickering as siblings do

Chilli loving satin bowerbirds, and migratory friends

Mimicking magpies

Female eastern koels, battling over a bloke

Ageing romantic sulphur crested cockatoos

A gorgeous grey goshawk

Bold bug eating birds

Whipbird 5 splashing crop

Poor lost souls

koel-mouth-open-cropped

There’s new sound in the garden just now.  A plaintive relentless cheeping.  But not the tiny piping tones of a naked, newly hatched chick.  No, it’s the muscular alto plea of the ginormous eastern koel chick to its diminutive red wattle bird parent.

And the wattlebirds are desperate.  I eyeballed the juvenile koel, lounging comfortably high in the canopy. Meanwhile its parent wheeled and fluttered in frenzied manner, perching here and pecking there, apparently driven to madness by the insatiable appetite of its parasitic offspring.

koel-and-mum-with-bent-neck-for-crop-amended-small

No sooner was the mega-chick fed than it returned to its incessant harping, as if unloved and cruelly abandoned.

koel-curved-neck-crop-real-crop

As I crashed around trying to get a clear shot of the elusive ear-splitting koel, I saw, at the top of the very same tree, something I’d never seen here before, something genuinely sad and alone.

flying-fox-illuminated-ears-cropped

A flying fox all by itself, a good twenty kilometres from the nearest bat camp way down the Pacific Highway at Gordon.

Flying foxes are very mobile, travelling up to 120 kilometres a night to feed.  We often hear them around our place on summer evenings, squealing and hurling fruit around.  During the year they migrate long distances following the peripatetic flowering seasons of eucalypts, melaleucas and rainforest trees, pollinating as they go.  Just like giant warm blooded bees, they carry pollen on their fur from one fragment of forest to another.  Flying foxes have been tracked moving as far as two thousand kilometres over the course of nine months and bat encampments have been described as more like railway stations or youth hostels than places of permanent residence.

But mega bats are sociable creatures and finding one on its own in the daytime like this is not a good sign.  I realised later I should have called the local WIRES group so someone with more expertise and a better head for heights than me could shin up its extremely tall tree to check it wasn’t injured by any of the usual suspects – barbed wire, open weave fruit netting or a dog bite.  But by the time I worked that out, it was the next morning, and the bat was gone – back to its digs in the local “Batpackers”, I hope.

I know some people feel about flying foxes the way I do about brush turkeys.  If you’re a fruit grower in NSW it is still possible to get a licence to shoot them to protect your orchards, although the mega bats actually prefer pollen and nectar as a food source – and  tightly secured, finely woven netting (one you can’t poke a finger through) protects crops better than a shotgun anyway.  In my backyard, the bats would be at the back of a very long queue for the ripe fruit anyway.  Ahead of me, of course, but behind the cockies and the possums for sure.

Deforestation means that there’s more conflict between flying foxes and humans these days, as the bats move into  the leafy suburbs where the fruiting and flowering plants are diverse and well watered.  They’re chatty critters with some “interesting” habits – urinating on themselves and then fanning their wings to cool down for one – which some people living nearby can find a hard to take (not to mention a couple of rare but deadly bat-borne diseases).

But the visibility of flying foxes in east coast Australian cities conceals the fact that (unlike brush turkeys) their numbers are in major decline.  One article suggests that at current rates, the grey headed flying fox, the type I found in my backyard, will be extinct by 2070.

The mega bats are particularly susceptible to high temperatures.  They start to “melt from the inside” in the words of a scientist, at just about the same temperature that is unsupportable for stingless bees, 43 degrees C.  A couple of years ago in Queensland,  45,000 megabats, mostly the tropical black flying fox, died in one day during a heat wave.  But high temperatures may just be the final straw when bats are short of food anyway.

Over the last couple of weeks, there have been scores of baby grey-headed bats found dead in parks along the east coast.  Both habitat loss and the aftermath of an El Nino, according to researcher Peggy Eby, have led to a food shortage.

“The mothers are going through a difficult nutritional phase, and they’re reducing the amount of milk they’re producing and the young starve.  They hang on to the females for the first several weeks of life, when she flies from the roost at night, and they simply would lose the strength that they need to hold on.”

I’m not sure why this stray found its way to our yard.  I hope it wasn’t injured here.  We don’t have a dog or barbed wire and we use veggie nets to keeps the bowerbirds and the brush turkeys off the fig trees (or if we’re feeling cheap, old trampoline netting from the side of the road).  But we still haven’t raised the cash to chop down the nasty cocos palm that is so appealing and yet so dangerous to flying foxes.

I hope the neighbours’ pool gave was a spot for a cooling bellydip and the jungle at the bottom of the yard gave it somewhere to recoup, recalibrate its GPS and get ready to head back to its pals at base camp.  Lovely as it was to have the chance to take his photo, I hope we hear him but don’t see him again.

Fly in, fly out

The first asparagus is up.  The greenflies are sucking the life out of the few broad beans plants that survived the gnashers of the garden’s winter visitors.  The bowerbirds are brutalising the new growth on the liquidambar, in a jaunty colourised style that makes me think we have a flock of Calamity Janes in the canopy.  Spring is here!

But what about the spring birds?  I haven’t heard the first koel of the season, but the channel billed cuckoos have squawked their way into our dreams.  And in the last week, a new rolling trill in the trees: the olive backed orioles have returned.  We rarely see them around here, but according to Michael Moorcroft’s “Birds of Australia” as “common”.  The emergent twitcher in me sighs.

I met a charming French skin specialist once, and asked her why she moved to Sydney.  “We have melanoma in France of course” she said “But really, if you are interested in skin cancer, Australia is the place to be”.

On the other hand, if you long for the sight of that first feathered visitor arriving from a epic transcontinental journey, you’re better off in the Northern hemisphere.  All the ocean in the southern half of the globe, moderating seasonal temperatures; barriers of forest and ocean; a less icy past; uncertain rainfall and an often arid climate; and (somewhat unconvincingly) weirdly, lots of  “V” shaped continents; all reasons I’ve come across to explain why we have so few migrating birds around here (Someille et al 2013; Dingle 2008).

Back home, two thirds of my French oncologist’s local birdlife would be part time residents.  But in Sydney, it’s maybe one in five.  In the outback there are nomads, roaming around trying to find things to eat in an arid landscape, but there are hardly any regular migrants at all.

silver-eye-chestnut-4-crop-larger

Tasmanian silvereye mid-migration, Zosterops lateralis lateralis

What we do have lots of in Australia are “partial migrants”.  Somewhere between a third and a half of bird species have some sedentary individuals while others take off in the colder weather (Chan, 2001).  Most silvereyes, for instance, stay put, but many Tassie birds – chunky numbers with chestnut sides, like the one above – fly across the Bass Strait in winter, possibly island-hopping as they make their way to Victoria, NSW and Queensland.  On my way to work the other day, I was was befuddled by the strange appearance of a crew of migrants – on their way home, perhaps – milling around happily in the company a bunch of plain-brand silvereyes.

Hard working bird lovers have been tagging silvereyes for 30 years (Chan, 2001), so we know what these guys are up to.  But in general, partial migrants are tricky customers – figuring which of the identical birds you see are interstate visitor and which are locals is mostly pretty hard to do.

After reading a bit about research on bird internal navigation systems, I’m starting to think this kind of deviousness may be payback.

One set of experiments involved keeping captive birds and observing what corner of their cage they batter themselves against, driven by migration-restlessness or Zugunruhe (one of those cool German words for which there is no English equivalent).  Researchers messed with the heads of these captive birds, using mirrors to shift the apparent direction of the sun so they could see what new quadrant of their cage they try to escape through.  Other experiments placed caged birds inside a magnetic coil to warp their sense of direction – a research activity truly worth of evil genius from X-Men. Although I do find the thought of a bunch of 1940s songbirds flooding into a planetarium – another early experiment – quite charming (Burton 1992).

 

dawn-moon-best-tight-crop

If you do see a trans-continental migrant in Australia, it will probably be a shorebird.  About 35 beach loving species migrate here (Dingle, 2008).  On a paddle up Mooney Mooney Creek last weekend, I was really happy to see one of them: an eastern curlew, its absurdly long beak mucky after joyously feasting on the mud-flat crabs off Spectacle Island.  Flying from Siberia will take it out of you. Between the bloody photographers, the houseboats and the jet skiiers, it’s not hard to see why these guys are classed as critically endangered around here.

 

 

References

Burton, Robert (1992) Bird Migration, London: Aurum Press

Chan, Ken (2001) “Partial migration in Australian landbirds: a review” Emu, 2001, 101, 281–292

Dingle, Hugh (2008) “Bird migration in the southern hemisphere:
a review comparing continents” Emu  (108), 341-59

Somveille M, Manica A, Butchart SHM, Rodrigues ASL (2013) Mapping Global Diversity Patterns for Migratory Birds. PLoS ONE 8(8): e70907. doi:10.1371/
journal.pone.0070907

Going cuckoo

You’re suddenly awake.  It’s very very early in the morning.  There’s an loud, insistent two-note call right outside your bedroom window.  It goes on and on and on, each time inching up in pitch, getting more and more desperate until it’s pretty much a hysterical squeak.  Just when you think the bird’s going to start outright screaming or explode, abruptly it stops.  You settle down in bed.  And then it starts again.

Or it’s the middle of the night.  Somewhere in the darkness, there seems to be a huge, angry and deeply confused seagull, belligerently squawking in disgruntlement and disgust: “Where the hell’s the beach??! And where are my chips!!!?”

It’s spring and they’re back.  Koels with their plaintively annoying round-the-clock cries, and channel billed cuckoos, raging at midnight (and during the day as well).

I heard my first koel, bang on time, the day after the vernal equinox; a raucous channel billed cuckoo interrupted one of my classes a few days before.  They’ve flown in from the north in time for the breeding season.  Sydney: it’s officially spring.

Despite their loud voices I have only ever eyeballed koels a couple of times.  On both occasions it was a whining juvenile that got my attention.  Down the bottom of the garden a year or two, I watched a great galumphing teenager begging for takeaway from a  motherly if diminutive wattlebird. We’re still working on installing LBB (little brown bird) habitat around here.  In the meantime wattlebirds rule the roost, along with magpies, kookaburras, rainbow lorikeets, cockies, brush turkeys – the usual self-confident generalists and anthropophiles (is that even a word?).  Which suits the koels fine, since red wattlebirds seem to make great parents.

Channel billed cuckoos prefer currawongs and occasionally magpies as babysitters, and since a mob of maggies has been hanging out at our place over the winter, I wonder if we might get an in-situ “fig hawks” or two as well.  My dad spotted a mega-cuckoo at the top of the drive last weekend, so it just might happen. Surprisingly, considering its deafening cries and outlandish hornbird-esque appearance,  no-one knows much about what the channel billed cuckoos get up to in their spare time.   So, go, backyard birdwatchers, go! Do that citizen science thing!

For all the mystery, it seems these guys, like the brown cuckoo doves, cooing outside the kitchen window in a more decorous and paradigmatically cuckooish way, are some of the winners of the anthropocene.  They like us and our tasty fruit-bearing trees.  And they favour the parenting style of the other birds that enjoy the buffet. Currawongs have come down from the mountains in the last forty years to snack on Sydney’s privet and lantana, and the visiting cuckoos are pretty happy about it.

Reflecting on how much these birds seem to enjoy our company, I’m tempted by a “humans-as-brood-parasites” line of thinking.  Begging for food from our animal compatriots, all the while chucking their babies out of the nest. Terminating the blood lines of the things that came before us in a flash and replacing them with more and more of our own offspring.  Bigger, noisier and more devious than the critters that feed us and house us.

But let’s not go there.  It’s a nasty thought, and whatever we might say about humans, cuckoos just aren’t that bad.