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….

 

 

 

Battle of the baby birds

There’s a festival of death going on in our neighbourhood at the moment.

Several times a day, amongst the robotic clicks of the bower birds and the squawks of the wattlebirds, there’s an insistent high pitched chittering call, often accompanied by the din of freaked out noisy miners.  I’m not 100% sure of its ethological or evolutionary significance, but as far as I’m concerned it’s a signal for me to drop everything and dart up our drive with my camera.  One of the resident pair of collared sparrowhawks – probably the male – has caught some small clueless bird and is perched in our neighbour’s radiata pine steadily eviscerating it.

He rips off the feathers and flings away less tasty bits (check out the beak mid-air above) all the while, often with his mouth full, calling out “Dinner’s up!” to his mate.

For the last few weeks she’s been spending much of her time in a the nest at the very top of another decrepit pine tree in the yard of next house along the way.  Sometimes he flies up to the nest with tasty chunks of flayed bird flesh in his claws, but I’ve also seen her fly in to the designated “disembowling” perch to join him a few times.  Occasionally, she seems to sneak away to do a little light hunting herself.  Risky, though, leaving the nest unattended.

There’s the pied currawong I saw hopping surreptitiously through the branches, warily inching towards the nest, until it was chased off by the indignant parents as it was virtually peeping over the side.  And the pair of cacophonous channel billed cuckoos I caught flapping around the neighbour’s garden a few weeks ago – apparently they sometimes parasitise collared sparrowhawk nests.

But I will be deeply unimpressed if the chicks that come out of that nest are bloody channel billed cuckoos, for all my secret admiration of those giant hornbill beaks and strapping crucifix silhouettes.

Because the sparrowhawks seem to have rid our garden of the plague of baby brush turkeys.

A whipbird seems to have taken up residence this spring.  Needless to say, I don’t have a photograph despite being nearly eye to eye with the noisy bugger once or twice.  So, tiptoeing round my backyard trying to catch a clear shot, I heard a scrabbling in the leaf litter.  “Ah, a baby brushturkey” I thought sagely.

And then it struck me… I haven’t seen a single baby turkey in our backyard this year.  Not one!  Last year, they were sleeping on top of the predator proof cage or standing outside in the daytime, gazing longingly at our flock of little baby chooks.  The year before one wandered into our pocketsized laundry and spent eight hours pacing the two foot long windowsill, failing to notice and thus escape through through the wide open door.  But this year… nada.

Collared sparrowhawks (unlike their lookalikes brown goshawks – so similar that it’s altogether possible they could be our resident raptors) catch most of their prey in flight, bursting out of their lurking places in the foliage to grab little birds on the wing.  But the baby brush turkeys that previously haunted our place do fly, right from the day they dig themselves out of their hatching place in their father’s mound of decomposing leaf litter, and start their life of unnaturally early independence.

So maybe the sparrowhawks have been catching them on those very first short flights from mound to chicken yard.

I don’t hate brush turkeys, but I do hate a having dozen brush turkeys hanging out in my backyard, sexually assaulting my chickens, nicking their food and, given half the chance, eating their eggs.  So the idea of generations of sparrowhawks breeding happily in the neighbour’s trees and keeping the local population to manageable levels is extremely appealing.

I’m starting to wonder if there’s a connection between the familiar sound of chainsaws and the plague populations of brush turkeys in Brisbane and the northern suburbs of Sydney over the last few years.  No dingoes, fewer foxes foxes thanks to baiting, and nowhere much for the local raptors to nest in suburbia these days, the tallest trees victims of fears about bushfires and death-dealing or at least car-damaging falling branches.

But today my endless blurry photos of the neighbourhood raptor nest brought good news: what seems to be a creamy ball of fluff snuggling up to its mum in the distant collection of sticks that is the sparrowhawk’s nest.  Bring on the next generation of brush turkey assassins!