Black princes, redeyes and floury bakers

My brother the twitcher has taught me the secret of finding birds.  Tune into sound: let your mind move out from the place where you are standing, into the space above you and all around you and listen.

All this summer, I’ve been listening out for the sparrowhawks.  Even lying in bed or sitting on the sofa, we could hear them begging for food or squabbling with the local cockatoos.

But come mid December, white noise and static started interfering with Radio Sparrowhawk.  The cicadas had arrived.

This year’s a biggie for cicadas in Australia.  Over 350 species of cicada have been described here, though there could be many more – we’re a diversity hotspot for these charismatic insects.  And this summer, some of the biggest and noisiest species – the cherrynoses, the double drummers and the razorgrinders – have appeared en masse around Sydney.  After maybe five or six years of living metres underground sucking on the tree-sap, the cicada instars crawl out of the earth and shed their exoskeletons for a short and noisy month or so as adults.   It doesn’t happen every year.  2013 was a big year for cicadas in Sydney, and before that 2010.  And now it’s on again.

Black prince 1 closeup nice background

Black Prince on a casuarina tree by the edge of Berowra Creek

No-one knows quite what triggers the horde of insects.  In fact, no-one knows much about cicadas at all, despite their presence on every continent except Antarctica and their impossible to ignore, earsplitting calls.  That long and decidedly boring youth, and the uncertainty about when they’ll re-emerge, makes researching them tricky.  Imagine deciding to study the periodic cicadas of North America and then realising your three years as a PhD student would be over long before the seventeen years the critters spend underground was up?

An ex cicada thanks to the local orb spiders

One theory is that by appearing so infrequently and irregularly cicadas could avoid the predators – bird, bats, all sorts of mammals – keen to feast on the insect bounty.  Very weird recent work from the US suggests that numbers of predating bird species start to drop around twelve years after the last cicada boom.  Could it be that these devious insects are manipulating the beasts far higher up the food chain?

In some ways, despite its wealth of cicadas, Berowra is less interesting for researchers than bits of Sydney not surrounded by national parks.  Australia cities are unusual, it seems, in that they still have cicada species in the heart of suburbia.  Silver princesses and green grocers survive in quite urban areas on the east coast. A local researcher (plants by day, cicadas by night) Dr Nathan Emery has been trying to work out how these species have survived, and whether there are others that can cope with city life. He’s set up the Great Cicada Blitz, a citizen science project crowd-sourcing information about when and where various species of cicadas can be found.

I’ve had a great time over the last month wandering around recording the din in our neighbourhood and trying without a lot of success to spot the earbleedingly loud cicadas to add to the Blitz database.  The male cicadas’ strategy to collectively produce a chorus so loud it hurts the ears of birds works on humans too, even those with the advantage of being partially deaf already. Apparently even the males cicadas “switch off” the equivalent of their ears (their tympana) to save their own hearing.

Thanks to helpful tips from the experts as they confirm my dodgy IDs, I’m slowly learning how to identify the common species around these parts.  Nathan Emery’s nifty little book A Photo Guide to the Common Cicadas of the Sydney Region has been really handy too. It has a lovely introduction from (and is dedicated to) Dr Emery’s scientist dad who took him and his siblings out cicada spotting as kids – inspiration to continue tormenting my offspring with my nerdy passions.  And who wouldn’t be nerdy about cicadas – an animal whose wings has in-built nanostructures that literally rip bacteria apart…

Graphical abstract

Graphical abstract for Aaron Elbourne, Russell Crawford and Elena Ivanova’s 2017 article “Nano-structured antimicrobial surfaces: From nature to synthetic
analogues” Journal of Colloid and Interface Science 508 603-616.
Shouldn’t EVERYTHING have a graphical abstract?

I should also thank the popularity of the big liquidambar in our front yard with the local insects for the chance to improve my cicada identification skills.  Adult cicadas like to latch onto thin-barked natives, but if push comes to shove they will feed on introduced trees, and liquidambars seem to be a favourite, of our local population of redeyes at least, although I think I’ve also heard calls from local tibouchina and robinia trees, as well as the local Sydney red and blue gums.

Though some cicadas don’t seem to be too fussy about the trees they sup from, you have to worry for the next generation.  In the last year, 15,000 trees – 3% of the tree cover on private land in Hornsby Shire – disappeared, thanks to a rash of tower buildings replacing the old fibros with rambling jungly backyards that used to hug the railway line.  Next gen cicadas popping out about 2023 may find nothing taller than a cordyline to sing from and property developers taking over their traditional role local bloodsucker.

Rough barked tree with cicada shell bettersquare

An exoskeleton clinging to the bark of a tall tree in a local school

I’ve not seen any green grocers or yellow mondays or silver princesses around here.  There are double-drummers in the national parks down the road – they don’t do so well in back gardens, needing an expanse of acreage or bushland to survive.  And so far we’ve heard at least four species around our yard: razorgrinders, black princes, floury bakers and the locally ubiquitous redeyes.

One of a whole bunch of redeyes high up in a Sydney red gum raining down excess tree sap on me

How do I know the red eyes are one of the most common cicadas around these parts, even before I started collecting photos and audio?  Well, that’s the gossip from the local kids.

Cicadas weren’t a feature of my childhood, growing up by the River Murray in South Australia.  But they’re a big part of children’s lives around here.  Even the common names of the local species are courtesy of kids, which explains why they are named after colours or days of the week and not dead white European men as per normal service!

My younger daughter (Anonymous Bob as she wants to be known) gave me the low down on what Berowra kids know about cicadas:

“At school in the cicada season, when the teachers aren’t looking, people climb the trees to try to catch cicadas. They climb the big thick trees because that’s where you find them. The main cicada zone is the little mossy grove next to the library. We treat them like exotic pets and look after them, until they want to be free or they die.

Once, there was a little boy. An older boy gave him a cicada to look after – it was sort of like an adoption. But the little boy decided to let him go so he could be free.

Another time, a bunch of kindies robbed a guy of his cicada. It was freshly caught and it had one leg missing, so he was desperate to protect it. They wanted to call it Princess and he wanted to call it Jeffie. They threw a ball at it while it was clinging to his shirt. It nearly fell off and died. And then the kindies started chasing the guy saying “Princess! Princess!” and then they had an attempted robbery but then a teacher came.”

Jeffrey Princess

“It’s fun to look after the cicadas. They’re kinda cute. Most cicada collectors try to find other species because in our school the redeyes are the most common. We find what they eat and take care of them. The cicadas cling onto your clothes which makes them pretty portable pets.”

Red eye cicada

Red eye at our place

“A while ago we did a thing where we would prank the teacher with cicada shells.   At first it was just a joke and then it became a whole fiesta. It became a game and a compulsory activity. Not that the teacher said it was a compulsory activity, we just made it one.

Originally it was just seven cicada shells a day but it ended up with many many many shells from each person. We gathered cicada shells, and every day we would leave cicada shells around the classroom and she would have to find them.”

Many cicada shells

A very popular grapefruit tree in my neighbour’s garden

“We found the cicada shells everywhere – on plants, on trees, on everything. A few boys were the main gatherers. They did it at school, home, everywhere. They came in with huge plastic bags full: they were the main source of our cicada shells. Sometimes we used white out and sharpies to paint war paint onto the cicada shell to make them unique.

Cicada on key ring

Graphical abstract of cicada exoskeleton on teacher’s key ri

You know how cicada shells have a slit? We slipped that onto the teacher’s key ring and when she found it, she was like “Not again!”. We started making a joke that she was cursed by the demon of cicadas.

At the very end of the year a few of the boys laid the cicada shells in a big love heart on the carpet and put a huge pile of chocolates in the middle and wrote their names on a card with love to the teacher.”

 

Cicada love heart

The love for a teacher expressed in the language of cicadas

Maybe there’s another project to be done on cicadas – a children’s natural history of these rowdy, charismatic insects…

Do you have any stories of childhood exploits with cicadas, in Australia or further afield?  I’d love to hear them!

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

 

 

 

 

 

 

Beekeeping without pain

“Do you still want that hive of stingless bees?”

Are there people out there who say no to the offer of a thousand tiny flying pets?  Perhaps there are, but I’m not one of them.

So when my marvellous friend Laura decided to divide her hive of native bees – Tetragonula carbonaria, the variety of Australia’s 11 species of stingless bees most commonly kept in backyards – I was certainly not going to look a gift bee in the mouth.  Even if I was able to inspect the teeny mouths of these diminutive 4mm long critters.

Laura was able to share the joy because about every 18 months a healthy hive of these highly social bees doubles in size and can be divided to create a new colony. There’s no worries about finding a queen for each of the two new hives.  European honey bee queens sting their rivals to death, but in a charmingly democratic process, the queen for the new colony of native stingless bees is selected by the workers from the emerging virgin queenlets hanging around waiting for their moment. This thought pleases me almost as much as the factoid acquired from my new bible, Tim Heard’s (2016) The Australian Native Bee Book, that bees are kind of like wasps that evolved to become vegetarians. My new pets are a vego workers’ collective.

Splitting hives is how Kuring-gai Council’s WildThings bee programme (that, via Laura’s benificence, has made us beekeepers) has distributed 900 hives around NSW.  And it’s how the number of meliponists – the appealingly pretentious name for keepers of stingless bees – tripled between 1998 and 2010.  Carbonaria are opportunistic snackers and seem to like it in the suburbs, with their mishmash of local and introduced flowering plants.

There are around 1600 types of native bee in Australia.  We’ve put up a lovely poster by Gina Cranson of some of the locals on our back door to try to improve our bee-spotting skills.  But of the highly social Australian stingless bees T.Carbonaria is the one that copes best with a temperate climate, with a range that extends from the Daintree to the NSW South Coast.

Here in Sydney it’s getting on the chilly side for them, so we won’t be able to harvest sugarbag from our hive.  Our bees will need the pots of honey they stash around the beautiful and distinctive spiral shaped brood comb, along with their surprisingly large reserve of pollen, to make it through the cooler months.  Stingless bees produce a lot less  than European bees anyway – a kilo or so a year, compared to up to up to 75 kilos – although sugarbag is apparently delicious.

We can’t steal sweet treats from them, but our tiny pets won’t be idle.  Native bees don’t seem to be vulnerable to varroa virus, the nasty bug threatening bee health the world over that may spread to Australia any day now.  So I can be sure that my mango, macadamia and avocado trees will have pollinators in the eventuality of a bee-pocolypse… assuming I don’t succeed in killing the trees (or the bees) first.  Happily, however, given my patchy track record as a farmer, our new friends will happily roam up to 500 metres away, well beyond our wonky fence line in search of tucker.

You don’t have to walk bees, desex them, groom them, clip their nails or pick up their poo (although in winter the “house bees” can’t be bothered carrying the dunny can too far from the nest, so if you choose to keep stingless bees on your verandah and you are the sort of person who is troubled by piles of barely visible dung you might need to invest in a nano pooper scooper).  But of course, despite that, I have managed to find something to worry about.

Stingless bees don’t like spells of frosty weather or very very hot days.  If it’s over 42 degrees inside the hive the whole damn lot of them can die.  So I was a bit antsy when Sydney had a couple of sizzlers in our first week as bee keepers.  The spot we’ve picked out for them is shaded by vines and protected from the afternoon sun, as well as catching the morning rays in winter time.  And our hive is wrapped in a polystyrene cover to insulate the colony against temperature extremes.  Once we’ve had them for a year or two we might take Laura’s approach: “tough love”.  But because we don’t really want to execute our bees (to be referred to collectively, the kids have decided, as Bob) before we even get to know them, this time we rigged up a bit of extra shelter and some evaporative airconditioning.

The only trouble with polystyrene is, as all chicken keepers know, it’s like crack to birds.  They don’t have too many taste buds and for some reason they can’t get enough of that squeaky mouth feel.  The gaggle of teenaged brush turkeys that loiter in our backyard hoping for leftovers from the chooks obviously decided that bees with a side-order of synthetic aromatic polymer would make a refreshing after-dinner snack.

Maybe I’ll come to regret the peace loving nature of the vegan commune in the backyard.