Verandah renovations — Fire-tailed Resin Bees (Part 2)

Four years ago I wrote about Fire-tailed Resin Bees (Megachile mystacaena) making sticky resin nest chambers in gaps between the weatherboards on our old verandah (see here).

Over the last two months I’ve been sanding and painting this part of the house. Simple job? No, typically for me this has been an epic struggle that, due to all sorts of problems, has expanded to fill endless weekends. Having sanded and painted over a red base coat that seemed solid, I discovered that as the new dark top coats of paint heated up in the afternoon summer sun, the old base coat (possibly enamel or lead-based paint dating back many decades) would apparently release a vapour that caused the newly dried top coat to blister.

Weekends of re-sanding and re-painting, on mild mornings and sun-blasted afternoons, followed. The entire time, the constant buzzing of native Fire-tailed Resin Bees, arriving and departing around me, formed a sonic backdrop to my endeavours. We became well acquainted, and my fascination with these tiny lodgers grew in parallel with my frustration over my painting abilities.

Verandah before

Dodgy photo of dodgy verandah renovations by dodgy renovator, plus small dog. All photos, except where otherwise credited, by Robert Ashdown.

A buzzing announces the arrival of another flight from the world beyond.

Out of my way human, I’m on a mission.

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Heading for an appealing gap in the timber.

Hover for a bit, then lurch forward into a space. Note the delicate hairs that cover these charming insects.

Touch-down!

Time to get to work on messing up my fresh paint. Good spot this, thanks.

There are about 2,000 species of native bees in Australia. They are extremely diverse in terms of size, shape and colour. Our bees are classified into five families, three of which are known as ‘short-tongued’ and two as ‘long-tongued’. The ‘tongue’ is actually a flexible hairy extension of the proboscis used for lapping up nectar and for applying secretions during nest-building.

Some other native bees I’ve encountered (above). Click on a thumbnail for a larger image.

Most of our native bees, including the Fire-tailed Resin Bees, are also lumped into a group known as the ‘solitary bees’. Solitary bees do not have queens, workers and drones, and so do not share a nest like European Honey Bees. However, I’ve discovered that they aren’t entirely ‘solitary’, as they do like to build nests for their young in the same great spots as others of their species. My verandah is apparently one of these prime bits of real estate.

Female bees mate and then seek tunnels or cracks in just about anything for their nests. The tunnel is lined with resin and is filled with some pollen, nectar and a single egg.

In solitary native bee species, the adult bees generally only fly during the warm months and die before the winter. Immature bees remain sealed in their cells inside the nests during the winter. They develop into adults and emerge when the warm weather returns.

On the verandah, bees (all females as I now knew) arrived constantly, carrying plant material in their mouths or with abdomens covered in pollen. Some air-traffic control was sorely needed. I witnessed mid-air crashes and bees wrestling with each other over the best spaces. I’d have them crash into me or over-fly and end up lost inside the house. They drove the dog nuts. Carrying heavy loads of plant material, some would skitter about on the new wall paint trying to get a grip before slipping and falling toward the floor, coming around for another go at speed.

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On several occasions I’d put a paintbrush down and place a finger carefully under a slipping bee so it could get a foothold. My wife suggested sanding the new paint near the nest hollows, and this seemed to help them land. Clearly, these bees were becoming a serious distraction.

Trying hard to get a grip on slippery new dried paint.

Plenty of hollows for everyone …

… unless two bees like the look of one space.  I reckon one bee here is clearing out, or cutting through, the work of another.

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Grrr… trouble, trouble. The girls are grumpy. Or maybe not … possibly sharing a space? Sounds ‘social’ to me.

Crash-landing, luckily (this time at least) onto unpainted part of the verandah floor.

Oblivious to my expensive wet paint, the bees would throw out black crumbly resin, which of course got stuck in the new paint. Ants would be attracted to it, and then they’d get stuck. There are no workshops on coping with this at Bunnings, Mitre 10 or Masters.

Busy, busy bee.

A day’s building waste litters my newly painted floor.

I’d have to apply new paint to the edges of the bees’ nest sites in the cooler mornings, before the bees got active. Otherwise they’d get paint all over themselves, which then stressed them (and me) out.

While painting the floor one morning, a bee, with its ‘weight-to-lift ratio’ ruined by paint on delicate wings and backside, crash-landed on its back and became stuck to the floor. Carrying the bee carefully in a small decorative Christmas bowl with some water, I sat on the back steps and washed paint off the bee with a tiny paint brush as the dog looked on jealously. She hates bees, which are irritating and need to be dominated, since they are in her domain and should be under her control (like us). Helpfully, my long-suffering wife remarked that “My Christmas bowl is not meant for washing paint off bee bottoms!” Possibly accurate.

Eventually, the bee dried off and took off skywards. Returning to the front verandah with paint brush, I spied another resin-laden bee just barely clearing the wet-paint floor. The dog immediately took umbrage, zooming past me and chasing the bee all over the verandah, before running back through the house with paint-covered feet! My shouts further convinced my already suspicious family that my fragile sanity was crumbling. This was becoming a debacle, a combination of my renovational incompetence and the demands of my insect tenants. There was only one solution — give up painting, pick up a camera and attempt some more bee photos.

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Luckily, resin sticks to Dulux Weathershield paint. Maybe I should let the company know that their products are native-bee certified.

I think this particular bee is dusted with pollen. Spectacular.

Watching these insects, I ended up with some OK photos and a lot of questions, some of which I’ve listed here, with tentative answers.

Are these all male or female bees? How long do they live? Some bees spend the night in their nest chambers — where do the others go after dark?

Male bees play no part in nest construction or brood care, they just spend their time looking for females to fertilise. They usually do this by patrolling the flowers or the nesting areas. Competition for females can be intense and males may fight each other to gain access to females. Territorial behaviour is quite common where males defend a patch of habitat, often containing forage flowers, and drive off rival males and any other flying insects.

Males of many species apparently gather at night in one place. I’d seen this once with another species of native bees — Nomia Bees.

Male Nomia Bees cluster together for the night. Toombul, Brisbane.

Middle of the night. All is quiet on the verandah, some bees asleep in their nest spots.

What exactly are they doing out of sight in the wall cavity?

It seems that the plan is something like this:

  1. Gather pollen and/or nectar from the garden.
  2. Bring back resin from a  source somewhere out there.
  3. Avoid the wet paint, dog and amateur renovator.
  4. Line the walls of the chamber with resin.
  5. Deposit some food material for their larvae in the chamber.
  6. Lay an egg in the chamber with the food.
  7. Seal off the chamber completely.

The Western Australian Museum reports that while both sexes of resin bees feed on nectar, females usually thicken it into honey before taking it back to their nests. They do this by regurgitating the nectar onto their mouthparts, exposing it to the air to evaporate excess water. They alternately regurgitate and re-swallow droplets of nectar until it reaches the required consistency.

Females of most kinds of bees carry their pollen loads on specialized sets of hairs (termed ‘scopae’) on either the hind legs or the underside of the abdomen. Such pollen loads immediately distinguish the insects as bees. Bees in the family Megachilidae carry pollen on the underside of their abdomen. Unlike honeybees, they do not have pollen baskets on their hind legs.

Out in the world away from the verandah, a fire-tail obtains nectar from a flower. This beautiful photo courtesy of Erica Siegel.

These bees have strong mouth-parts for chewing up plant material and fashioning stylish resin nests.

A bee approaches — abdomen conspicuously coated with bright yellow pollen.

Pollen and honey are usually combined in the nest to form the larval food, either as a solid, rounded mass or as a fluid or semi-fluid paste. Either way, the egg is deposited on top of the completed provision. Each brood cell is a cavity providing a protective environment for the development of a single individual; it is stocked with sufficient food to enable development from egg to adult and is sealed once it receives an egg.

I noticed that several bees sometimes seem to use the same chamber — is more than one egg laid in a chamber by different bees?

Where does the resin come from?

The resin they are using at my place is a deep red/purple colour. They are reported to use resin from eucalypt species, but there are not too many gum trees in our suburban block now. The nearest resin or sap I’ve seen is leaking out of local camphor laurel trees, and some pine trees, in a local park about 500 metres away — I wonder if they use resin from these exotic species?

The purple colour of the resin can be seen on this completed cell.

Some bee-keepers have reported resin bees hanging around stingless bee hives, trying to ‘borrow’ a little resin for their nests. They have been seen ‘balling up’ the resin with their front  legs, although the bees bringing resin back to our place seem to be carrying it in chunks. They appear to work it into place with their jaws, and I’ve also watched them rubbing their abdomens on the resin. Are they secreting something to help work it into shape? Some species have also been recorded chewing leaves to add to the mix.

A bee approaches the wall with a prize chunk of resin firmly gripped in the mouth.

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Working the resin into place.

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In the USA, researchers have investigated native resin bees, from the same genus as our fire-tailed species, incorporating pieces of plastic shopping bags into their nests in addition to the usual leaves, as well as sealing the nest cavity with plastic-based sealants, including caulk.

The study offers another example of how animals adapt to human-dominated environments. “There will always be those that have adaptive traits or enough flexibility in their behavior to persist in a disturbed landscape,” they report (see link below).

What happens to the larvae?

Once hatched, the eggs progress through larval stages and subsequently will overwinter as pupae. Young bees must bore their way out of their cells and find their way to freedom. Bees that nest in hollow stems and borer holes construct a series of cells, end to end along the galleries.

I’d sometimes discover tiny bee larvae on the verandah floor in the morning. One was still alive so I attempted to get it back in a nest chamber. I can only assume that some bees remove the larvae of other bees at night as they compete for the best nesting hollows.

They face some dangers. The Western Australian Museum reports that bees’ worst enemies are mould, mites and parasitic insects — certain wasps, flies and beetles.

I sometimes observed other flying insects hovering around near the bees and finally managed a (bad) photo of one on my phone. I think this is a parasitic wasp of the Chalcididae family. These attempt to break into the bees’ freshly completed brood cells to deposit their eggs. The wasp or parasitic bee larvae, upon hatching, destroy the host egg or young larva and take over the food store.

Look out bees! A predatory wasp looks to lay an egg on bee larvae. Danger! Danger!

Bad news for a bee. Parasitic wasp on the prowl.

Are native bees important pollinators, and how are they going in general?

Native bees are important and efficient pollinators of a wide range of plant species — including crops and native species. They are also in trouble. Wild and native bees the world over are declining in numbers or disappearing completely.

While it is true that native bees are not experiencing ‘colony collapse disorder’, they suffer from many of the same problems that the more ‘glamorous’ animals are experiencing. Chief among these are loss of habitat and habitat fragmentation. And when the habitat is lost, native food sources and nesting environments vanish as well.

Native bees are also subject to the pesticides. All types of pesticides have been found to harm bees, including fungicides, herbicides, acaricides, rodenticides, and of course the ubiquitous insecticides. Since native bees are closely tied to their food source, anything that destroys the food source—whether it’s a herbicide, a freeway, or a housing development—destroys the native insects that were dependent upon it.

A park here, a field there, and a garden down the road are not enough to maintain populations in the long term. Habitat fragmentation destroys the ability of populations to freely intermingle, and soon the genetic pool becomes small and lacks diversity. This is a major step on the road to local extinction. Add enough local extinctions together and a global extinction will follow.

— Native Bee Conservancy

Russell Zabel outlines the known reasons for declines in populations of Australian native stingless bees, and these reasons would surely apply to many species of Australian native bee:

Native Bees are found in the hollows of dead or damaged trees. There are a number of reasons for their reducing population:

a. Land owners generally do not leave trees to grow old and die, therefore hollow trees are scarce.
b. Dead trees are considered a danger to livestock breeders and are therefore removed.
c. There is a possibility that poisons used for rural applications are killing out these delicate little insects.
d. Land developers are using the technique called ‘Selective Clearing’ to improve the sale potential of their allotments. Consequently, we see the trees containing native bees dozed into a heap and just burnt.

At the same time it’s clear that, as with so many components of our biodiversity, we don’t even have the full picture about what’s out there. New species of insects, including bees, are being discovered all the time. For example, in September 2015, four new native bee species were found in the Pilbara region of northern Australia. Three of these new species have special narrow heads and unusually long mouth-parts that allow them to feed on the slender flowers found on emu bush, a hardy native of the Australian desert.

Talking about resin bees to a bunch of fellow naturalists at the November meeting of the Toowoomba Branch of the Wildlife Preservation Society of Queensland.

By late January, there are nine separate nest chambers either finished or under way on our verandah. Some of the bees have tattered wings, a sure sign of a long, hot nesting season. Perhaps their short life spans are running down. I have huge admiration for these fearless builders.

It’s now mid February and the mornings and evenings are slowly getting cooler. The verandah is finished, and so are the bee’s resin nest chambers. There is no sign of any visiting bees — perhaps their short adult lives have come to an end. While we sit and enjoy the revamped verandah, the next generation of resin bees are slowly growing inside the walls. I hope we’ll see them around again next Summer.

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A verandah just isn’t complete without ornamental orange bees.

LINKS

Thanks to Erica Siegel and Russell Zabel.

Chasing dragonflies

Dragonflies are a lot of fun to watch, but tricky to photograph. Lots of patience is needed. Here are some images from an afternoon trip to Murphy Bridge, at Iredale in the Lockyer Valley.

I was messing about with an old Nikon MF zoom lens on my Olympus OMD EM1. The results aren’t perfect, but you get the idea. Such wonderful insects!

Click on the top-right blue icon for a larger slide show.

Stormy skies

Summer storms, dramatic skies. Photos by Mike Peisley and Rob Ashdown.

[Click on images for closer look.]

Storm heading east over Boonah, from Toowoomba escarpment. Photo R. Ashdown.

Moreton Bay storms brew, from Shorncliffe. Photo M. Peisley.

A storm sweeps north-east near Injune, central Queensland. Photo R. Ashdown.

Moreton Bay, from Shorncliffe. Photo M. Peisley.

Storm over Moreton Bay, from Shorncliffe. Photo M. Peisley.

Stormy sunset skies, Toowoomba. Photo R. Ashdown.

Queens Park, Toowoomba. Photo R. Ashdown.

Lightning strikes the ocean, Moreton Bay. Photo M. Peisley.

Storm north of Injune. Photo R. Ashdown.

Storm heading east over Boonah, from Toowoomba escarpment. Photo R. Ashdown.

Jacarandas and stormwater., Toowoomba. Photo R. Ashdown.

Storm over Moreton Bay, from Shorncliffe. Photo M. Peisley.

After the storm, Toowoomba. Photo R. Ashdown.

The edge of the storm, north of Injune. Photo R. Ashdown

Wet powerlines reflect the setting sun, Toowoomba. Photo R. Ashdown.

Full moon and the sun’s last rays, looking east from Toowoomba, January 2016. Photo R. Ashdown.

Platypus of Carnarvon Gorge

I’ve been visiting Carnarvon Gorge (part of Carnarvon National Park), on work trips as part of my role with the Queensland Parks and Wildlife Service, for about 15 years. In all that time I’ve never just sat by Carnarvon Creek and taken a determined look for one of the park’s most iconic creatures — platypus.

I’ve seen them briefly while walking creek-side at Carnarvon, but it’s never been much more than a glimpse. My childhood memories of platypus are mixed. As a young lad, standing fairly close to David Fleay during one of his platypus shows at his West Burleigh reserve, I marvelled at the mysterious creature that moved into view in the concrete display tank. Unfortunately, the memory is scarred by the recollection of either my brother or I accidentally kicking an empty coke bottle across the floor, not long after Mr Fleay reminded all of the utmost need for quiet and even no finger pointing. The scornful glance of the legendary naturalist was memorable.

So, on another recent quick work trip to Carnarvon, I headed down to the creek about 4.30am to see if these things really existed. If lucky, I’d get to see one, and maybe I could capture a photograph or two of the mysterious beasties. I had no hope for anything too successful photo-wise, as I’d no intention of using a flash on such shy creatures and platypus are well known for not being photogenic in the wild (like any sensible animal).

First crossing at Carnarvon Creek. A calm place at 4.30am. Click on images for a closer look. All photos R. Ashdown unless otherwise credited.

I took up a spot above the bank and sat quietly in the grass, scanning the slowly brightening waters of this marvellous creek.

Carnarvon Creek is a magical place. The water always flows, part of a process that has endlessly and relentlessly carved through basalt and sandstone to create one of Australia’s most wondrous gorges.

Multi-hued and sun-dappled creekside vegetation, as well as towering sandstone cliffs and woodland perched high above the gorge floor, are reflected in the creek’s waters. The icing on the cake is the array of animals, of which surely the platypus is the most elusive and mysterious, that call this creek home.

A quiet stretch of water. The perfect place to seek a platypus.

After a short time just sitting, a movement caught my eye. A wake was spreading out behind a moving brown lump. It was a platypus, motoring across the surface of the creek. I held my breath and tried not to kick any coke bottles.

Over the next hour, and again the next morning with a colleague (Raelene Neilson, some of whose photos are included below), I followed the progress of two platypus as they worked their way around a large, still part of the creek, not far from the visitor area.

A platypus morning seems to be spent drifting and motoring about like a tiny barge, interspersed with frequent diving and searching in the sediment for yabbies and other food. A trail of bubbles tells of a platypus searching for food on the bottom of the creek.

A swirl of bubbles indicates a platypus is grubbing about in the sediment below seeking breakfast.

Platypus are found along the east coast of Australia as far north as Cairns, down to the bottom of Tasmania and as far west as Adelaide. They are one of two monotremes (egg-laying mammals) found in Australia, the other being the Short-beaked Echidna.

Platypus live for up to 12 years in the wild and approximately 20 years in captivity because there are no predators or seasonal changes. Their tunnels, in the bank of the creek, can be from 15 to 30 metres long, and there is usually more than one entrance just above the water line. The burrows are a tight fit so that water is squeezed off their fur when a platypus enters the tunnel. Platypus have a high amount of haemoglobin in their blood, which allows them to make better use of available oxygen, so they can survive high levels of CO2 in their tunnels.

Platypus are venomous. The males have a poisonous spur on each hind ankle, which is capable of causing severe pain in humans. The female’s spurs fall off at the juvenile stage. Platypus at Carnarvon Gorge apparently only grow to around 30 cm long, possibly due to the small size of the creek, and the number of platypus living in it.

A platypus diet consists of shrimps, larvae and some insects. They find food by rummaging through the creek bed with their bill. Platypus usually feed for 10 to l7 hours a day, depending on how much food is about.

During winter and early spring females start consuming larger quantities of food and use the tail as a fat storage area to be used in the breeding season, as the female fasts for about a week after the eggs are laid.

Platypus usually mate from July to September. After conception there is a gestation period of four weeks and then three eggs are laid. The eggs are oval, light brown in colour and smaller than a twenty-cent piece. They are soft and laid in a sticky substance which allows the eggs to stick to the mother's underside for incubation. The mother stays in the burrow, which is lined with leaves and grass, for approximately seven days and after this period only goes out to defecate. During the whole process the female has the tunnel blocked off, keeping predators out and humidity high. Each time the platypus exits the nesting burrow she takes down the wall and rebuilds it. The young are incubated for 10 days and once the eggs hatch they are drawn to a milk secretion area between the mothers front and hind leg enabling the young to ingest milk. The young are fed for three to four months at which time they begin to emerge from the burrow. Photograph by Raelene Neilson.

Platypus usually mate from July to September. After conception there is a gestation period of four weeks and then three eggs are laid. The eggs are oval, light brown in colour and smaller than a twenty-cent piece. They are soft and laid in a sticky substance which allows the eggs to stick to the mother’s underside for incubation. The mother stays in the burrow, which is lined with leaves and grass, for approximately seven days and after this period only goes out to defecate. During the whole process the female has the tunnel blocked off, keeping predators out and humidity high. Each time the platypus exits the nesting burrow she takes down the wall and rebuilds it. Photo by Raelene Neilson.

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The young are incubated for 10 days and once the eggs hatch they are drawn to a milk secretion area between the mothers front and hind leg enabling the young to ingest milk. The young are fed for three to four months at which time they begin to emerge from the burrow. Photograph by Raelene Neilson.

 Messing about in the water ... or something. Photo by Raelene Neilson.

Messing about in the water … or something. Photo by Raelene Neilson.

Checking out the humans — total weirdos. Photo by Raelene Neilson.

Checking out the humans — total weirdos. Photo by Raelene Neilson.

Platypus tend to share areas and tunnels. The adult males are fairly territorial and only meet to fight over females during mating season, but females and juveniles will feed through a range of territories and generally rest in the burrow that’s closest. Colonies of platypuses keep at a fairly set level, and if conditions are not able to support the juveniles, they are forced to move on.

Carnarvon Creek reflections (click on image for closer look)

It’s a serene body of water — usually. However, as the rangers working here know, this quietly flowing creek has a wild side. Every now and then, floodwaters rage down the gorge system in an immense, turbulent  show of power, tearing out creek-side trees and rolling huge boulders.

A flooded Carnarvon Creek, January 1976. Photo by Bill Morley, QPWS.

A worn and battered creek boulder bears evidence of the power of a 2012 flood.

Ranger Erin Witten is dwarfed by piled up debris from another flood, 2007. Photo QPWS.

How do platypus survive such times?

Surely some of them are killed. Perhaps they are able to wait things out in their burrows, but it’s hard to imagine how they’d do this when the floodwaters can last for days. Or perhaps they sense the approaching floodwaters and quietly head away from the creek, returning when water levels  subside.

We have very few photographs of Carnarvon platypus on our QPWS files. One of them bears the caption “After the floods, the platypus come out”. I’d assume that this platypus has been photographed in the calmer creek waters not long after a flood.

Tom Grant, in The Platypus, a Unique Mammal recounts  that in the first five years of a 20-year study of platypus in the upper Shoalhaven River in New South Wales, seven floods occurred, all of which changed the river from its normal series of deep pools with connecting rapids into a raging mass of brown water with no distinction between pool and rapid. Their study found that while some platypus are killed, most were not even displaced from their home ranges by the floods.

As platypus have occupied the rivers of Australia for at least 50,000 years, they have presumably evolved strategies to cope with flooding, However, it is still unknown how they ride out floods. Early naturalists suggested that they occupy rabbit burrows and hollow logs away from the river, returning later. Some recent radio-tracking work has shown that platypus of the Goulburn River avoid high flows associated with the release of water from the Eildon Weir for irrigation used a backwater area to avoid the faster-flowing water. They even found that the animals would still enter the river to feed, paddling against the current. However, it would be hard to imagine them being able to feed easily during the raging Carnarvon Creek floods, at least during the wilder periods of flooding.

The Australian Platypus Conservancy reports how damage to creek banks and burrows happens with floods:

In theory, depending on their magnitude and duration, floods could have either a positive or negative impact on platypus populations. The effect of minor flooding is likely to be relatively benign and could even improve the quality of platypus habitat, for example by flushing accumulated silt from pools.

By comparison, severe flooding is much more likely to affect platypus populations adversely. The animals may drown, contract pneumonia after inhaling water, or be swept downstream and have to find their way back through unfamiliar terrain. Their burrows may also be inundated for a substantial period of time and food supplies badly depleted due to invertebrates being washed away.

Flooding can also degrade the quality of platypus habitat if it causes banks to erode, pools to become filled with sediment, or in-stream woody habitat (logs and branches) to be deposited on land as flood waters recede.

A study conducted by the Australian Platypus Conservancy in mid-2008 examined how platypus populations in four Gippsland rivers were faring approximately 9–11 months after substantial floods occurred. In each case, flooding peaked at an estimated flow rate of more than 10,000 megalitres/day. In brief, the severity of flood-related habitat damage was inversely related to platypus population density and reproductive success: the river suffering the greatest damage had the lowest numbers of platypus and the smallest proportion of juveniles (none), whereas the least damaged area had the highest density of platypus and the largest proportion of juveniles. It was concluded that flood-related impacts can have a measurable adverse effect on platypus populations, particularly when (as was true in this study) the vegetation on adjoining slopes has recently been damaged by wildfire.

The fact that juvenile platypus are weaker and less accomplished swimmers than older animals suggests that they may be more likely to be killed by floods, particularly if these occur around the time that juveniles first emerge from the nesting burrow in summer. This is supported by the results of live-trapping surveys carried out in the Melbourne area after more than 120 millimetres of rain fell on the city in less than 24 hours in early February 2005 (the highest one-day total since weather records were first kept in 1855). The mean juvenile capture rate from February to June 2005 was less than 10% of the corresponding mean capture rate from 2001-2004. In contrast, the capture rate for adults and subadults occupying the same five water bodies from February to June 2005 was actually slightly higher than the corresponding mean capture rate from 2001–2004.

In his book Paradoxical Platypus — Hobnobbing with Duckbills, David Fleay describes the effects of floods on young platypus in south-eastern Queensland:

As a spin-off from my appointment as weekly Nature Columnist (1952-80) to the Brisbane Courier Mail, I was in touch with most platypus happenings in south-eastern Queensland. This proved not only invaluable but very instructive.

So in way or another, numerous duckbills passed through our hands, particularly those babes rescued from peril at the generally early south-eastern Queensland nest-leaving period (late December to early February).

At least four such inexperienced juveniles were actually flotsam in the mile–distant Pacific Ocean at the tail-end of cyclones. Naturally, sudden savage flooding takes victims by surprise and bears the unwary, willy-nilly into the sea.

Times of flood must bring turmoil to the quiet morning ritual that I was fortunate to observe at Carnarvon Creek.

While there is some evidence that platypus may be adapted to survive a natural event like a flood, the effects of humans on our waterways is far more detrimental to these mammals. Having survived hunting for pelts in the 19th century, platypus now face a far greater human threat — our impact on waterways due to agriculture, forestry, dam construction, mining and industrial activities. Illegal and inappropriate fishing practices, particularly the use of nets in creeks, also kill platypus. The health of platypus populations is inextricably linked to the health of our waterways, and our activities around these river systems. How we treat our creeks and rivers will determine how well platypus survive into the future.


I greatly enjoyed my brief time watching these unusual mammals. They were full of energy and life as they worked the creek in search of food, sometimes stopping to drift and seemingly take in what was going on around them.

The sense of privilege and wonder I felt while sitting next to that serene creek lingered. Back at my work desk, I paused from the cubicle chaos to think of the morning calm of Carnarvon Creek and its marvellous residents. I really hope they’ll be messing about there forever.

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Carnarvon Creek. An ever-flowing wonder in the heart of arid central Queensland. A joy for human visitors, a home for one of Australia’s most mysterious creatures.

Platypus below. Carnarvon Creek twists its way beneath the towering sandstone cliffs of Carnarvon Gorge for many kilometres. An ancient landscape full of surprises. Photo QPWS.

 

Links:

Arrowhead Rockmaster

A scorching summer day at Girraween National Park, and the dragonflies are everywhere. Some are sitting in the shade for a while, making photography of them a little easier.

Here’s a few photos of one of my favourites (actually a damselfly), the Arrowhead Rockmaster (Diphlebia nymphoides).

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Same place, different species. Rangers Karl, Jo and Neal on their lunch break explore a granite sink-hole, get in some band practice and attempt to stay cool for a few minutes by the creek.

In search of live Powerfuls

Along the moonpaths and under the stars, in fact, there is a world of intense and abiding interest known to few but open to all. — David Fleay

Not far from Toowoomba is a valley where  Powerful Owls have been hanging out for years. I recently went on a search for them with naturalists Rod Hobson and Bruce Thomson.

Unfortunately, dead Powerful Owls seem to be more common than live ones around here. While it’s always depressing to see how many animals are killed on our roads, you do get to find out what lives where (assuming there are some other living specimens in the area), and you sometimes get a close look at some animals that are difficult to see up close in the wild.

 An electrocuted Powerful Owl hangs from wires, Prince Henry Drive, Toowoomba.

An electrocuted Powerful Owl hangs from wires, Prince Henry Drive, Toowoomba.

 Rod Hobson with a road-killed juvenile Powerful owl, Toowoomba.

Rod Hobson with a road-killed Powerful owl, Toowoomba.

An adult Powerful Owl can be up to 650 mm in length. These shy birds live in pairs and keep to large, permanent territories of up to 1000 hectares. They roost by day in tall forest trees.

Powerful talons on a powerful bird. These birds prey on birds and mammals, including Greater Gliders, possums and flying foxes. They also eat rats, birds and young rabbits. Powerful Owls need to eat the equivalent of a large possum every two to three days to survive.

Our walk up the valley was enjoyable, and we saw and heard many birds (and other wildlife), while peering about for the elusive giant owls.

A curious juvenile Eastern Water Dragon observes our slow progress.

Eastern Yellow Robin.

A native bee seeks minerals or moisture from a clay creek bank.

Ah, now we were getting somewhere. What was that lurking in the shadows ahead? It’s one of the elusive owls, watching us closely.

Photo courtesy Bruce Thomson.

Later on, we spot another owl, hiding deep in the shadows.

Rod and Bruce owl-spotting.

Again, Bruce captures a terrific image (I won’t show any of my dodgy efforts).

Each pair of Powerful Owls has a number of roosting trees, and they roost in different trees on different days, not always together, but within calling distance from each other. Their call is a loud, mournful, far-carrying “wooo-hooo”. Photo courtesy Bruce Thomson.

While watching these birds, and recently when listening to one calling at night in the Lockyer Valley, I thought of David Fleay and his wonderful 1968 book Nightwatchman of Bush and Plain, in which he tells of many nights spent in Victorian forests pursuing these owls.

Says G. M. Ward in his 1969 review of the book in The Victorian Naturalist:

Here, deep in the Korweingeboora forest, began the prelude to forty-two years of patient and painstaking study of the Powerful Owl.

The reader tramps with the author over miles of rugged country; and spends both pleasant nights and nights of being cold, wet, muddy and miserable. But always there is an expectancy that the roosting site of the Powerful Owl is near.

Right through … the reader is constantly aware of David Fleay’s unflagging patience and determination to eventually breed captively, this wonderful and lordly bird.

LINKS

Mouse spider

When people come across a large black spider they often think they’ve encountered a Funnelweb Spider. However, not all large black spiders are necessarily Funnelwebs.

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I recently had the opportunity to photograph this spectacular Red-headed Mouse Spider (Missulena occatoria), dropped off to the QPWS office from Oakey, on the Darling Downs in south-eastern Queensland. This spider was a female — the males have a deep red head and royal blue abdomen.

Mouse spiders are related to Funnelwebs and Trapdoor Spiders. They are all members of a ‘primitive’ group of spiders, from the Infraorder Mygalomorphae. These are among the largest and longest-lived spiders, and one of the oldest groups of spiders found in the fossil record. They have remained almost unchanged for tens of millions of years.

One of the things that is so special about macro photography is the wonderful detail in the resulting photograph that was often missed with eyes alone, especially when you’re reluctant to get your face too close to the subject! I love the fine red-hairs and the colours in the leg joints of this fabulous arachnid.

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The Queensland Museum (QM) website is a great source of information on Queensland spiders. They report that three species of Mouse Spider have been recorded in Queensland:

  • Redheaded Mouse spiders (Missulena occatoria)
  • White-backed Mouse spiders (Missulena bradleyi)
  • Small Black Mouse Spider (Missulena dipsaca).

Mouse Spiders are often confused with Funnelweb Spiders. There are differences in their morphology, although to see this might require a fair bit of care and courage if you’re not particularly enamored of our eight-legged wildlife (“Sit still, I need to see where your eyes are!”).

When viewed from the side, the head of the mouse spiders appears as a step, strongly divided into two levels by a nearly vertical drop from the front half of the head. The eight tiny eyes are spread across the front of the upper section behind the very prominent chelicerae. In funnel-web and all other trapdoor spiders the eyes are grouped together on a mound at the centre front of the head and the head is not strongly divided. — QM

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Mouse Spiders are apparently quite common in many Queensland suburbs,  but not often seen. From the QM website again:

They make a very well concealed burrow in the lawn or open ground. Often the web tube flops onto the ground and is soil-encrusted and hence well-camouflaged. Burrows may be located in lawns after rain by looking for small pyramids of soil beside which is a very well concealed tube.

The spiders are often found while gardens are being dug or soil turned over. Males wander from late Summer and tend to peak in April-May and often fall into suburban swimming pools whilst searching for females. 

There is ongoing research into these spiders and just how venomous they are. A recent confirmed bite to a young girl from one of these spiders caused a severe reaction. However, the girl recovered after receiving Funnelweb antivenin.

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The Queensland Museum mentions the enigmatic nature of these spiders and what is known about their venomous nature.

The seriousness of the bite of Missulena was until recently the subject of serious disagreement. We had recorded several reports of uneventful bites from Missulena species both males and females. Two reports stand out. In one, a 7-year-old boy had a female Mouse spider attached bull-terrier style to his finger. The GP had to crush the spider to get the fangs out. The boy complained only of minor hunger pains as in the excitement, lunch had been missed!

The second case was of a paramedic whose earth basement was almost swarming with male Missulena bradleyi. He was bitten repeatedly by the males in his sleeves. The immediate pain soon passed and he had no problems until 36 hours later when a large infected area appeared on his arm. He applied an antibiotic powder and the wound healed and was barely noticeable when we saw it a week or so later.

The late Dr Struan Sutherland’s research showed that these spiders were potentially more toxic than Funnelwebs; thus, we were at odds. Inexplicably, the Gatton baby recovered quickly when given Funnelweb antivenom. Clearly, the Gatton bite was what Sutherland had predicted but why did some victims not react?

Dr David Wilson, then at the Department of Drug, Design & Development, University of Queensland looked at the question. When Funnelwebs disturbed, they quickly rise to the defence pose with a drop of venom on each fang tip. However, although Missulena also rises to the defence pose quickly, venom is rarely seen.

It seems that the Mouse Spider rarely needs or uses its much smaller reserve of venom; presumably most of the uneventful bites were dry, i.e., without venom.

A male red-headed Mouse Spider, Isla Gorge National Park. Photo R. Ashdown and R. Mancini.

Links:

… and some more frogs

I recently stayed one night at Girraween National Park while on a work trip, and it was a stormy summer night. Perfect, of course, for checking the frogs around Bald Rock Creek!

Bleating Tree Frog (Litoria dentata)

Emerald Spotted Tree frog (Litoria peronii)

Broad-palmed Rocket Frog (Litoria latopalmata)

Stony Creek Frog (Litoria wilcoxii)

Clikcing Froglet (Crinea signifera)

Ornate Burrowing Frog (Platyplectrum ornatum)

There’s one species of frog at Girraween that I’ve never seen — the New England Treefrog (Litoria subglandulosa). Classed as ‘vulnerable’, this fog is only found in a small area of wet sclerophyll and heath country in the granite country of the Queensland/New South Wales border.To see an image of this beautiful species, check out this great image on this wonderful website on Girraween National Park.

Meetings with remarkable frogs

Any little dam or pond on a summer’s night, as long as it has some water and a bit of vegetation around it, can be a magnet for the frog-photographer (yes, there is such a niche in photography).

On a weekend escape with the family, as we sit on the verandah of rented cabin enjoying the fading late-afternoon light, a chorus of weird noises drifts up from a small dam just out of view, on the edge of some bush. Frogs!

I’m instantly trying to identify the callers, a habit formed many years ago when summer nights were often spent in the somewhat eccentric pastime of lurking in a muddy, mozzie-ridden swamp trying to find some tiny frog, while clutching cameras, flashes, cables and other paraphernalia.

Eastern Grey Kangaroos, and a single Red-necked Wallaby , hanging out on a slowly-cooling afternoon, and probably trying to identify the species of frogs they can hear calling.

The sun sets on this particularly warm spring day. There’s a dam down there somewhere.

“Are you looking for frogs too?”

I’m travelling a bit lighter with camera gear these days. I grab my Olympus OMD-EM1, a 60mm macro, a single flash with off-camera cable and head down to the dam to take a look.

I’m soon reminded that it’s always harder to find frogs than I remember.

A racket of various sounds assails my ears as I approach the dam, which is surrounded by vegetation and covered in water-lilies. Where to start? I pick a weird little ‘riiiiiiik’ sound in the grass and sneak up on the culprit.

Of course the frog hears some monster with the sun strapped to its head approaching noisily and, sensibly for a small vulnerable amphibian, stops calling. It seeks a mate, not some huge predator, and has no desire to be the subject of a dodgy blog post by some nocturnal swamp-wandering weirdo.

I move on to the source of another of these sounds, only to have the same thing happen. Soon, I’m heading off to nowhere, no closer to finding the tiny frog. If a fellow frogologist, sorry, herpetologist, was present, we could triangulate and move to the meeting spot of pointed fingers. X marks the spot. A secret frog-finding technique I learned from the Frog Photography Guild in my local chapter of the Illuminati.

However, I’m on my own tonight, as there was no chance of convincing wife and teenage son to attach head-torches and help me. They’ve been there before, remembering epic all-night expeditions that started with an innocuous  “Can you help me find this frog?”. They are more interested in finishing a game of Simpsons Monopoly (yes, there is such a thing).

When you’re on your own, you soon realise that frogs are amazing ventriloquists. They are never where their calls seems to indicate. However, I persist, returning to the first caller, and eventually spot the lurking little character. He’s a member of the genus Uperoleia, a frog group known commonly as Toadlets or preferably to me, Gungans. There are currently ten known species of these small frogs in Queensland, and they are all hard to identify to species level. I think I’ve found a Uperoleia rugosa, the Wrinkled Toadlet or Chubby Gungan.

“Oh no, the swamp-wandering weirdo has found me!” Chubby Gungans are about 3cm long and are great ventriloquists.

There are other tiny things wandering about at night, including this colourful spider.

One of the dam-side calls is quite distinctive, It’s a loud, manic, descending cackle — the laughing call of the Emerald-spotted Tree Frog, Litoria peronii. This is one of my favourite animals, a true character. It always make me smile when I hear their ridiculous call.

Emerald-spotted Tree Frog (Litoria peronii).

Stanthorpe weekend escape with Allana and Harry. Litoria peronii

It’s a bit hard to see the bright green spots on this frog, but they are there. They have wonderful bright yellow and black markings inside their hind legs. This is one of three similar species in Queensland that have green spots.

A sudden movement catches my eye as a frog leaps through the air in front of me. I track it down. It’s a Broad-palmed Rocket Frog, Litoria latopalmata. This species makes a series of rapid ‘quacks’ that accelerate then slow down.

Broad-palmed Rocket Frog (Litoria latopalmata)

A loud ‘bonk’ sound leads me to another favourite frog — the Eastern Banjo Frog or Grey-bellied Pobblebonk, Limnodynastes dumerilli. Limnodynastes means something like ‘Lord of the Marshes’.

One frogologist describes their call as ‘reminiscent of PVC pipe being struck by a rubber thong’. How would you know that? I guess you’d have to try it. Eccentric lot indeed. Pobblebonk, their other common name, is a great interpretation of the sound a bunch of these make when calling at once.

Grey-bellied Pobblebonk (Limnodynastes dumerilli)

Stanthorpe dam -016The most persistent call in the froggy racket is an almost deafening rasping, rickety call. Small green and brown frogs cling to feeds or occupy lily pads. These are delightful Eastern Sedge Frogs, Litoria fallax. Each frog is slightly different, their colour various combinations of greens and browns. They are like tiny jewels. I like them a lot.

Eastern Sedge Frog (Litoria fallax).

There’s at least one other species calling. I’m pretty sure it’s a Clicking Froglet, Crinea signifera, or possibly a Beeping Froglet, Crinea parinsignifera. I’m too tired to catch it, so here’s a pic of a Beeping Froglet I found one night in a road-side swamp in Texas, southern Queensland. It’d look something like this from a prone position in the mud (how I met this one).

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As I sloshingly return to the Monopoly players (Homer has been rendered bankrupt by Margie apparently), and the calls of the unfazed frogs fade behind me, I reflect on the many memorable meetings I’ve had with these critters over the years.

It may indeed seem odd to some, but I’ve enjoyed the moments spent with such magic creatures in the bush at night and count myself lucky to have met them. Long may we have such wonderful things out there somewhere in the night.

Here’s a quick rogue’s gallery of some of the frogs I’ve tracked down over the last few decades.

Southern Orange-eyed Tree Frog (Litoria chloris). Lamington NP.

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Giant Barred Frog (Mixophyes iteratus). Sunshine Coast

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Copper-backed Brood Frog (Pseudophrene raveni). Bundaberg.

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Eastern Gungan (Uperoleia laevigata). Tingalpa.

Copper-backed Brood Frog (Pseudophrene raveni).

Tusked Frog (Adelotus brevis). Mt Moffatt NP.

Emerald-spotted Treefrog (Litoria peronii). Dalby.

Litoria caerulea, Tingalpa, Brisbane.

Green Tree Frog (Litoria caerulea), Tingalpa, Brisbane.

Naked/Purple/Red Tree Frog (Litoria rubella). Windorah.

Fleays Barred Frog (Mixophyes fleayi). Main Range NP.

Holy Cross Frog (Notaden bennetti). Barakula State Forest.

Water-holding Frog (Cyclorana platycephala), Windorah.

Scarlet-sided Pobblebonk (Limnodynastes terraereginae), Tingalpa.

Fletcher’s Frog (Limnodynastes fletcheri), Bungunya.

Wallum Froglet (Crinea tinnula), Lota.

Ornate Burrowing Frog (Platyplectrum ornatum). Lota.

Pearson’s Tree Frog (Litoria pearsoniana). Minyon. I got lost in Minyon State Forest, in northern New South Wales, for about five hours after I finished photographing this frog. Ah, good times!

Australian adders

Common Death Adder, Acanthophis antarcticus, Bruce Thomson.

Common Death Adder (Acanthophis antarcticus), Bringalily State Forest. Photo by Bruce Thomson.

The Death Adder is one of Australia’s more unusual snakes. This post presents some recent photos of this reptile from around Queensland and northern New South Wales.

Maree Cali from Mackay spotted one of these highly venomous elapids close to her campsite. Says Maree, “I was excited to accidentally set up camp over the Easter break next to this cool customer and was blown away by its laid back nature, camouflaging ability and beauty — and I’m not particularly into snakes.”

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A master of camouflage, waiting for a meal to pass by. Photograph by Maree Cali.

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On the move! Photograph by Maree Cali.

Gerry Swan and Steve Wilson give an overview of Death Adders in their book What Snake Is That?

Australia is the only continent with no vipers, family Viperidae. In their absence, some elapid snakes of the genus Acanthophis have evolved to fill a similar niche. These sluggish, well-camouflaged and sedentary snakes lie concealed in leaf litter or under low shrubs and grasses. Important features of this group are a short, thick body, a broad head distinct from the neck and an abruptly slender tail.

Their similarity to vipers was not lost on early settlers, who were reminded of the Adder (Vipera berus) from Britain and Europe. They named the Australian snakes ‘death adders’ because of the high mortality from bites before anti-venom became available. The corruption ‘deaf adders’ may derive from their reluctance to move away when disturbed.

Death Adders are ambush predators that feed on a variety of vertebrates. The slender tail has a segmented tip and soft spine, and they lie with this resting near the head, When prey is detected, the snake wriggles the tail convulsively, mimicking a grub or worm to lure the animal within striking distance. Its ability to strike so suddenly and with such mind-boggling speed is unnerving to witness, particularly considering the snake is slow moving and prone to lie motionless for days on end. The strike is accurate and lethal, as a powerful venom is injected deeply through long fangs.

Death adder, captive specimen.

Death Adder, with strikingly patterned head strategically positioned near its tail (aka caudal lure!). Captive specimen, photograph R. Ashdown.

Common Death Adder. From The Snakes of Australia, by Gerard Krefft, 1869. Death Adders are not true ‘adders’, belonging instead to the same family as other venomous Australian snakes, the elapids. Their similarity to adders, which are actually members of the viper family, has evolved in response to the species’ environment and their ‘sit and wait’ style of life, which does not require a snake to be long and agile but short and muscular for a quick strike when necessary.

Kate Steel encountered a Death Adder near her back verandah of her house in northern New South Wales. Kate relocated the snake in a sack, grabbing a few photos on the way. She posted on Facebook, “Just caught this slithery under the verandah, there was a Willy Wagtail giving warning and then Lyly the alarm dog. Hope the photos are not too shaky cos my hand is!”

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A Death Adder being relocated from near the back verandah to somewhere less likely to be trodden on by bare feet. Photo by Kate Steel.

Queensland Parks and Wildlife Service (QPWS) Rangers often encounter snakes as part of their daily work. Ranger Stuart Fyfe took the following photos of a Northern Death Adder (Acanthophis praelongus) in far northern Queensland.

“I found this Death Adder pretty late one night outside the barracks common room, (around 11pm), so took a few photos then put him in a bucket to relocate him in the morning. We have a couple of families on base with small kids, so we tend to relocate these guys down the track.

When I first found him he was quite docile, and didn’t puff up even when I put him in the bucket, but when I released him in the morning he was all fired up — they tend to puff up like that when they are being defensive. He must not have liked being in the bucket overnight.”

Photo by Stuart Fyfe.

Death Adder scale patterns. Photo Stuart Fyfe.

Death Adder scale patterns. Photo Stuart Fyfe.

Death Adder moving out of grass to escape a controlled burn on national park. “This was one of the biggest we’ve seen up here. Based on the width of the Rake Hoe I estimate he was about 42cm long.” — Stuart Fyfe. Photo by David Delahoy, QPWS.

How dangerous are death adders to humans? From a Wikipedia article that lists details of deaths due to ‘unprovoked bites by snakes’ in Australia:

The estimated incidence of snakebites annually in Australia is between 3 and 18 per 100,000 with an average mortality rate of 0.03 per 100,000 per year. Between 1979 and 1998 there were 53 deaths from snakes, according to data obtained from the Australian Bureau of Statistics.

Between 1942 and 1950 there were 56 deaths from snakebite recorded in Australia. Of 28 deaths in the 1945-49 period, 18 occurred in Queensland, 6 in New South Wales, 3 in Western Australia and 1 in Tasmania. The majority of snake bites occur when people handle snakes in an attempt to relocate or kill them.

Australia is the only continent where venomous snakes constitute the majority of species. Snake bites in Australia that cause deaths are less common than they once were, because of increased medical knowledge and anti-venom that is better and more available. Around half of all deaths from snakebites are thought to be caused by brown snakes, perhaps as many as 60% of deaths caused by snakebite.

Unlike other snakes that flee from approaching humans crashing through the undergrowth, common death adders are more likely to sit tight and risk being stepped on, making them potentially more dangerous to the unwary bushwalker.

However, they are reported to be reluctant to bite. Richard Shine, in Australian Snakes, a Natural History, describes this apparent reticence:

There are many stories testifying to this docility, perhaps the most famous being of two men cutting sugarcane in a paddock. They spent the day working at the job, carrying loads of the crop frequently out of the gate to their nearby truck. It was late in the day that one of the workers noticed a large Death Adder coiled in  the dust in the middle of the path, right beside the gate, The dust showed hundreds of footprints from their bare feet within a few centimetres of the snake’s head.

Ranger Andrew Young recalls a family Death Adder encounter when  he was a lad growing up on the family farm at Stanwell, west of Rockhampton, in the 1960s. He remembers lots of yelling, and dancing about, associated with this particular snake sighting.

“My Dad had sent the farm-hand out to our other property at Ridgelands where he was to plough up some paddocks for planting sorghum.  When he was finished he drove the tractor back to our Stanwell farm for some more work we had there.  The farms were about 40 minutes drive apart by car so a good couple of hours by tractor.

When he arrived home that evening we all went to meet him and hear how he went.  During the discussion, he said, “Oh, and I found a great legless lizard today!”  He opened the tool box on the side of the tractor and hauled out this Death Adder!  Dad shouted “Drop it!” and we all leapt back — as you might imagine! I shall not recount the snake’s fate …

But I have always thought that the snake was indeed laid back as it didn’t bite when it was ploughed out of the soil nor when grabbed out of the tool box that it had been jiggling around in all day.”

Death Adder photographed in the Mount Moffatt section of Carnarvon National Park by QPWS Ranger Brent Tangey.

In its element. A Death Adder photographed in the Mount Moffatt section of Carnarvon National Park by QPWS Ranger Brent Tangey.

Many bites from Death Adders proved fatal before the introduction of antivenom.  Death Adder venom contains a type of neurotoxin which causes loss of motor and sensory function, including respiration, which can result in paralysis and death. Deaths from bites are still common in New Guinea.

How dangerous are humans to death adders in Australia? In reality, this snake is perhaps more endangered than dangerous. Despite being labelled ‘common’, the Common Death Adder is becoming increasingly less so. Gerry Swan and Steve Wilson write:

Death Adders have declined in many areas. They can be regarded as biological indicators of environmental quality as they appear extremely susceptible to degraded conditions. Weeds, altered fire regimes, introduced predators and toxic prey in the form of the introduced Cane Toad all play a part in the demise of these snakes from sites where they were once extremely common.

As Steve, who has pursued reptiles across the continent for decades, said to me when talking about Common Death Adders, “I defy anyone to call them ‘common’.”

Reptiles are beautiful and fascinating creatures. They are a fundamental part of Australia’s wonderful biodiversity — something that is under constant siege. Says Steve:

The loss of native vegetation has been the most substantial and urgent problem facing Queensland’s reptiles and other fauna. The estimated annual toll from broad-scale clearing between 1997 and 1999 was a staggering 89 million reptiles, a figure no doubt matched today as hundreds of thousands of the state’s extraordinarily complex natural heritage is bulldozed, heaped and burnt. Apart from the immediate individual casualties, the loss and fragmentation of habitat has implications at population and species levels. With the spectre of increased clearing for expanding coal and gas exports and the push for more northern development, it is critical that habitat continuity be prioritised.

I’m yet to encounter one of these snakes in the wild, but hope the chance to do so will be there for a while yet.

northern death adder, kuranda, north queensland HDR (Large)

There are five currently recognised species of Death Adder found in Queensland, though several distinct populations may prove to be valid new species. Between these species, Death Adders can be found over most of mainland Australia, except Victoria. All are live bearers, with litters of over 30 young recorded. This is a Northern Death Adder (Acanthophis praelongus). Photographer Greg Watson photographed this captive specimen at Kuranda (within the species’ range and of an animal with a size and the pattern consistent with the location).

Common Death Adder, Acanthophis antarcticus, Bruce Thomson.

Common Death Adder (Acanthophis antarcticus). Photographed on a QPWS fauna survey of Bringalily State Forest by Bruce Thomson.

A strikingly patterned Common Death Adder. Photo by Steve K Wilson.

A strikingly patterned Common Death Adder from central Queensland. Photo by Steve K Wilson.

For more information on the five Death Adder species found in Queensland, see A Field Guide to Reptiles of Queensland (second edition) by Steve K Wilson. The book contains some beautiful images of these snakes by Steve and fellow reptile photographers Angus Emmott and Gary Stephenson.

[Safety note: Death Adders are dangerously venomous. All photos on this post were taken at a safe distance. It’s not a good idea to test a Death Adder’s mood by touching one or getting too close with a  camera. Seek professional assistance in relocating a snake if you need to move one.]

Thanks to:

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Life on the edge

Grey Mangroves (Avicennia marina) at dawn, Lota, Brisbane.

Grey Mangroves (Avicennia marina) at dawn, Lota, Brisbane. All photographs Robert Ashdown.

One perceives a forest of jagged, gnarled trees protruding from the surface of the sea, roots anchored in deep, black mud, verdant crowns arching toward a blazing sun. Here is where land and sea intertwine, where the line dividing ocean and continent blurs.   — Klause Rutzler and Ilka C. Feller

If there are no mangroves, then the sea will have no meaning. It is like having a tree without roots, for the mangroves are the roots of the sea.   — Attributed to a fisherman from the Andaman Sea

The sun has just risen above Moreton Bay and the sky is catching fire. I’m standing in the incoming tide, in that edge zone where land meets sea. The waking suburbs are less than a kilometre away, but I can’t see or hear anyone. The rising sun doesn’t have my attention. I’m looking the opposite direction, back into a tangled mangrove forest, as the first rays of the sun hit the gnarled grey trunks. Everything in front of me has come together in a brief, quiet spectacle of light and shade, and I’m transfixed by the scene.

———

The edges of things are fascinating places to naturalists and photographers. Ecologists use the word ecotone to describe the edge zone between ecosystems. Landscape photographers revel in edges, the places where the land meets the sky, the ocean meets the shore — where lines draw the viewer into the scene.

Exploring the edge of land and bay. Amity, Stradbroke Island.

Exploring the edge of land and bay. Amity, Stradbroke Island.

With 125km of boundary (stretching from Caloundra to the Gold Coast), Moreton Bay has plenty of edges between land and water. These are diverse places, reflecting the bay’s beauty and contrasts — with mysterious mangrove forests, mud-flats full of life and sandy island beaches. Where the bay stops the growing city of Brisbane in its tracks, the human-built environment swallows these places in walls of concrete or canal estates.

Known as Quandamooka to Aboriginal people, Moreton Bay lies close to one of Australia’s largest cities.

Known as Quandamooka to Aboriginal people, Moreton Bay lies close to Brisbane, one of Australia’s largest cities.

Bushfires cloak the Glasshouse Mountains, at the northern end of Moreton Bay.

Bushfires cloak the Glasshouse Mountains, at the northern end of Moreton Bay.

Some of the bay’s natural edges have been replaced by the geometric patterns of canal estates. It is thought that about 20 per cent of the bay’s mangroves have been lost since European settlement.

Some of the bay’s gloriously ragged natural edges have been replaced by the geometric patterns of canal estates. It is thought that about 20 per cent of the bay’s mangroves have been lost since European settlement.

Luckily, there are places in Moreton Bay where the zone between sea and land is as it has been for millennia — blurred and hard to define. In 1799 Matthew Flinders couldn’t find the entrance to the Brisbane River because it was obscured by a wall of grey-green mangroves, plants which thrive in the shallow water and mud flats of this island-sheltered bay.

The word mangrove refers to a range of plants growing in the intertidal zone. This is an orange mangrove (Bruguiera gymnorrhiza), Coochiemudlo Island.

The word mangrove refers to a range of plants growing in the intertidal zone. Orange Mangrove (Bruguiera gymnorrhiza), Coochiemudlo Island.

Mangroves are, of course, important places — as home to marine life, crucial nurseries for the sea creatures our fisheries depend on, and buffer zones to storms and the power of the sea.

Important is a word that just doesn’t begin to cut it. It’s baffling then when we are reminded that some still seem to despise them, as when those who have claimed their patch of real estate by the bay see mangroves as an impediment to their view. Some even destroy them to improve their outlook, killing part of the thing they seek to enjoy, not understanding the basic truth that the bay is a vast living system, with many parts, not just some pretty vista captured within a window frame.

Australia is surrounded by approximately 11,000 km of mangrove-lined coast — around 18% of the coastline, and nearly half of this is found in Queensland. There are about 13,500 ha of mangroves on the edges of the Moreton Bay. Most are found near river mouths and in other areas protected from waves.

Australia is surrounded by approximately 11,000 km of mangrove-lined coast — around 18% of the coastline, and nearly half of this is found in Queensland. There are about 13,500 ha of mangroves on the edges of the Moreton Bay. Most are found near river mouths and in other areas protected from waves.

A grey mangrove seedling. Nearly 70 per cent of the prawns, crabs and fish we eat depend on the mangrove habitat for at least part of their lifecycle.

A grey mangrove seedling. Nearly 70 per cent of the prawns, crabs and fish we eat depend on the mangrove habitat for at least part of their lifecycle.

Many probably still see mangrove forests as smelly, horrible places crawling with mozzies, snakes, spiders and crocodiles. Explore one though, and light and time slip away. As the sounds of the land fade, other noises are heard — clicks, splashes, the clear piping of a mangrove kingfisher or the sweet, falling leaf call of a mangrove gerygone. There’s a gradual realisation that these muddy, shadowed places are full of life.

A Soldier Crab displays its maroon knees.

A Soldier Crab displays its maroon knees.

The highly venomous, but charmingly beautiful Blue-lined Octopus.

The highly venomous, but charmingly beautiful Blue-lined Octopus.

Blue swimmer, Moreton Bay.

Blue swimmer, Moreton Bay.

So where does the sea actually start or end in a mangrove zone? There’s no set spot of course, this is the intertidal zone, where the water ebbs and flows with the endless tides.

At low tide, old mangroves look like stranded, strange creatures, patterned by lichens and ringed by water-marks. They are partially consumed each day as the incoming tide pushes past them toward the land beyond. In king tides and storms the sea reaches beyond them to saltmarshes and samphire flats, sometimes even popping up in the drains and streets of bayside suburbs like some kind of unwelcome intruder.

Image 6_(c) Ashdown

Image 7_(c) Ashdown
On this morning I have waded out before dawn into the mangroves, carrying a camera and binoculars. I’m close to the suburbs but may as well be lost somewhere on Australia’s vast northern coastline, sent back in time to when there were no cities chewing up the bush beyond.
I’ve gone as far as I can, having pushed out beyond the edge of the mangroves.

As the sun rises and the first orange light hits the wall of mangroves, the wind drops and calm descends on the scene, allowing glowing reflections a brief window of life. Realising that this will only last a minute or two, I steady my camera on a shaky, mud-stuck tripod and capture one long exposure. Then, the wind rises, the moment vanishes, and a restless movement fills the mangrove forest as a new day takes over.

A dragonfly is warmed to life by the sun's first light. Lota Creek mangroves.

A dragonfly is warmed to life by the sun’s first light. Lota Creek mangroves.

Man, boat and pelicans, dawn, Wynnum.

Man, boat and pelicans, dawn, Wynnum.

Weeks later I get the developed slides back and realise that this single sunrise mangrove image (the first image on this blog post) will be a favourite photograph of mine, one that will have the power to transport me from the stress of busy life to the quiet wildness of the mangroves, still there I hope, greeting each day amid the endless rhythm of the tides, home to myriad creatures, important — and just being its mysterious, magical self.

Mangroves at dawn, Wynnum North boardwalk

Mangroves at dawn, Wynnum North boardwalk

A full moon rising over St Helena Island is framed by a grey mangrove.

A full moon rising over St Helena Island is framed by a Grey Mangrove. Wynnum North.

Wildlife of the Lockyer Valley calendar 2016

The Wildlife of the Upper Lockyer Valley calendar for 2016 is now available for ordering.

Burton’s Snake Lizard. Photo Robert Ashdown.

Proceeds from the sale of this calendar go toward The Citizens of the Lockyer Inc. This community group aims to increase awareness of the rich biodiversity to be found throughout the Lockyer Valley and to promote the adoption of sustainable lifestyles in this unique rural environment.

The calendar features some wonderful images from Bruce Thomson, Mike Peisley and Russell Jenkins (and a few from me), and includes information about the area’s wildlife from naturalist par-excellence Rod Hobson. Design was by the talented Rob and Terttu Mancini of Evergreen Design. The calendar was produced through an Community Environment grant from the Lockyer Valley Regional Council.

Graphic Flutterer. Photo by Bruce Thomson.

Wedge-tailed Eagle and Magpie. Photo by Russell Jenkins.

Scarlet Honeyeater. Photo by Mike Piesley.

Copies are $15 (+ postage) and can be ordered from Roxanne Blackley at bioearth@bigpond.com.

Brachychitons by night

My photographic exploration of these intriguing trees continues.

On a cool evening at Highwoods on the Darling Downs I watched the fading light soak into textured bark. As eerie silhouettes against a starlit sky, these trees seem otherworldly and ancient, reaching silently toward the Milky Way.

[Click on the images for a larger view]

Thanks to Martin, Rod and Mark. See also: Bottle Trees at Highwoods, Brachychiton survivors and Brachychitons Part 2.

The Simpson revisited

Simpson Desert, western Queensland.

The Simpson Desert. All photos in this post by Robert Ashdown.

The scene was awfully fearful, dear Charlotte. A kind of dread (and I am not subject to such feelings) came over me as I gazed upon it. It looked like the entrance into Hell.
[Explorer Charles Sturt on encountering the edge of the Simpson Desert, September 1845.]

In 1996 I spent some time on the edge of the Simpson Desert. Not much time, and not far into the desert, but it was a memorable adventure.

As an image I’d taken on that trip was recently chosen for the cover of a book on macroevolution (the evolutionary and ecological processes responsible for generating patterns of biodiversity), it seemed like a good opportunity to post some slide scans, accompanied by a few words written for an article published in the Summer 1996 edition of Wildlife Australia.

Looking west across the Simpson Desert as the light fades.

Looking west across the Simpson Desert as the light fades.

The Simpson Desert. To some the name may conjure images of lifeless sand dunes, of a stark and deadly landscape. To visiting naturalists, the Simpson is a place of subtlety, surprises, life, colour and great contrasts.

The Simpson Desert covers part of three states at the arid centre of Australia. More than 1,000 parallel sand ridges, often running unbroken for great distances, form a unique landscape. It is one of the world’s great sandy deserts.

Lobed Spinifex (Triodia basedowii) forms hummocks on dune crests. It provides refuge for many species of desert fauna.

Ctenotus pantherinus

Ctenotus pantherinus ,one of many species of beautiful reptiles that call this arid area home.

Parakeelya.

Parakeelya.

Central Military Dragon (Ctenophorus isolepis).

Canegrass dragon, Diporophora winneckei.

Canegrass dragon (Diporophora winneckei) playing dead.

Aboriginal people lived in this desert for countless generations, basing their lives around wells and an intimate contact with the desert plants and animals. Early Europeans saw it as a dead zone — devoid of flora and fauna of any real value.

Vegetation in the swale areas between sand ridges.

Vegetation in the swale areas between sand ridges.

Brown falcon.

Brown falcon.

"Desert

The Desert Grevillea (Grevillea juncifolia) is one of the many desert plants that can survive long periods without rain. I watched Black Honeyeaters coming over the sand ridges to land in them for a brief nectar refuel.

Ghost Gum and spinifex in afternoon light.

Ghost Gum and spinifex in afternoon light.

These notions faded as expeditions and surveys revealed an astonishing biodiversity. Far from being a monotonous and lifeless wasteland, the Simpson Desert encompasses a variety of constantly changing land-forms, each providing habitat for many superbly adapted plants and animals. New and exciting biological discoveries are continually being made.

To the visiting photographer, the Simpson is overwhelming. The vast, silent landscapes do not easily reveal their secrets. In a  dry creek bed between sand ridges, we share the midday shade with a host of birds.

Dry creek bed, Simpson Desert.

The dry bed of Gnallan-a-gea Creek, Simpson Desert.

Flowering bloodwood, Gnallan-a-gea Creek.

Flowering bloodwood, full of birds. Gnallan-a-gea Creek.

Tangled mulla mulla.

Tangled Mulla Mulla.

Grasshopper and desert sand.

Grasshopper and desert sand.

The change from afternoon into night is soft and magical. As the sun  sinks, the red sand on the ridges glows with a luminous intensity. The shadows of the wildflowers and other plants lengthen.

Silence returns and cloaks everything with a palpable intensity, The dome of the sky sweeps down to invade the ground as the twilight colours fade and the horizon vanishes, Another day in  this remarkable place has ended.

Ghost Gum and full moon.

QM photographer Jeff Wright looks after the campfire in dry creek bed.

Jeff Wright looks after the campfire in dry creek bed.

Varanus gilleni, a small species of goanna found wandering about the creek bed at night.

Gillens Moniter (Varanus gilleni), a species of small goanna. We found wandering about the creek bed at night.

And who ended up on the cover of that book? A character I’d been hoping to meet.

Thorny Devil tracks, with boot tracks of photographer seeking reptile.

Mysterious tiny tracks (on left), with the boot tracks of photographer in hot pursuit.

Thorny Devil (Moloch horridus)

Found! Thorny Devil (Moloch horridus) photographed  at last.

LINKS:

Tigers on the move

There’s always something to discover in a Queensland backyard if you’re into natural history, even if it’s a fairly ordinary one like ours.

Returning from an early Saturday morning walk, the dog and I were stopped in our tracks. Our flowering Ivory Curl Flower tree (Buckinghamia celsissima) was alive with a swirling mass of Blue Tiger butterflies.

With the recent rain and heat our desert-like yard evolved into a weedy suburban Amazon, and with the green came the insects. Lots of them. Bladder Cicadas deafened all at twilight, Garden Orb-weaver spiders made each trip to the bin at night an arm-waving obstacle course and Scarlet Percher dragonflies buzzed us in our dodgy inflatable pool.

Blue Tiger butterflies swirl about our Ivory Curl flower tree, a magical Saturday morning coincidence of flowers and migrating butterflies. Text and all photographs by Robert Ashdown. Click on an image for a larger version.

However, this swirling mass of butterflies was something else. Standing under the tree, I could see a stream of the fluttering insects doggedly heading toward our house from the south-west. As they neared the Ivory Curl Flower they’d drop immediately, landing and seeking nectar, oblivious to observers. Native stingless bees buzzed about dodging the butterflies as well as the tiny flower spiders seeking to capture a meal. A microcosm of insect activity centred on this one magnetic tree.

Blue tiger butterflies feed on certain plants to obtain pyrrolizidine alkaloids, chemicals that make them quite unpleasant to animals trying to eat them. They have also been observed drinking from moist sand in the dry season.

The Blue Tiger (Tirumala hamata) is one of the butterfly species that sometimes moves in enormous numbers across southern Queensland — others include the Caper White (Belenois java) and the Lemon Migrant (Catopsilia Pomona). The Blue Tiger is a member of the Danais group which includes many migratory butterflies, the most well-known of which is the Monarch. The Monarch undertakes huge regular migrations in America and even managed an overseas trip, arriving in Australia in the 1870s, possibly blown this way by cyclones or travelling as larvae stowed away on plants that subsequently became weed species here. Once established in Australia, the Monarch settled down to a more sedentary life, only undertaking less-ambitious journeys from inland areas to the coast as the temperature drops with winter.

Blue Tigers are also found in the Philippines, Indonesia, Solomon Islands, Fiji, Tonga and Samoa, In Australia, they breed in monsoon forest (vine thicket) and littoral rainforest in south-east Queensland, or around Darwin in the wet season when larval food plants produce new growth.

The introduced plant Lantana is a favourite source of nectar for many butterflies. Lockyer Valley.

Blue Tiger butterflies can be hard to spot during winter but large numbers can still sometimes be found. Winter is a tough time for butterflies as host plants are unable to offer fresh foliage for larvae to feed on and fewer nectar sources are available. Some Australian species, such as the Blue Tiger, have a survival strategy: they gather in large numbers and put their lives on hold for the winter. This dormancy, or ‘aestivation’ (also known as ‘overwintering’) buys adult butterflies time. In summer an adult may only live for one to two months; however, a butterfly that has overwintered can live as long as nine months. Those few extra months may mean that winter butterflies can make it through to the spring, a much more favourable breeding time. Blue Tigers have been found overwintering in vine forest in sandy gullies and creek banks, resting on branches or twigs close to the ground.

[CLICK ON IMAGES ABOVE FOR LARGER VIEW]

In spring and summer, they take to the air, often in huge numbers. Some claim that we are currently experiencing the highest number of butterflies seen in south-east Queensland for 40 years. When interviewed by the ABC, Queensland Museum curator Dr Christine Lambkin explained that the numbers were due to a combination of rain and heat providing perfect breeding conditions for these insects.

“We have had a long extended dry period that has been broken by good rains at the right time of the year,” she said. “So we have got the warmth as well as the rain and that is what has caused the adults to break the aestivation, which is the insect hibernation, and emerge in numbers. Some of them will be trying to mate and lay eggs so that the caterpillars are going to come up on that flush new growth (of butterfly food plants) from the rain.”

With numerous pale blue streaks and elongate spots, the blue tiger is an attractive insect. The pupa of this butterfly is a shiny green with gold spots that turn silver. The caterpillars are grey with black bands, orange lines and long filaments. They feed on vines found in dry rainforest scrub.

Are the Blue Tigers heading anywhere in particular? According to old mate Google, the online consensus appears to be that this species heads south from northern Queensland in spring and summer, moving through Brisbane (where they are normally not often seen) in large numbers. They have been recorded reaching as far south as Victoria. However, other observers have recorded them heading north, as seen at our place this year.

Queensland Parks and Wildlife Service ranger Rod Hobson recounts watching huge numbers of blue tigers “ … flying north into the never-never of blue off the end of Sandy Cape at Fraser Island to perish at sea. I used to find large numbers of dead blue tigers in the beach wrack for days after these events.” It’s hard to imagine what they were seeking in the Pacific Ocean, if they had a destination in mind.

Strangely, when seen flying about later in autumn, Blue Tigers appear to be moving in different directions. I asked entomologist Chris Lambkin if the butterflies were perhaps being blown in one direction by prevailing winds. Chris does not believe this is the case; she has seen them moving east into the wind.

While butterflies are perhaps the best-known group of insects, much remains to be known about their taxonomy and ecological requirements, important information if we wish to conserve them.

So it seems we don’t know why they head in one direction. Clearly, the movement of butterflies in Australia is not well understood. Some research has been done — Dr Courtenay Smithers at the Australian Museum initiated a tagging program for butterflies in the 1970s, which gave some idea of the seasonal movement of Monarchs in Australia and discovered some over-wintering sites for the species. However, not a great deal appears to have been discovered about butterfly travel plans in the decades since. Much of what has been written on butterfly movement has appeared in the newsletters of ever-active organisations  such as the Butterflies and Other Invertebrates Club and Land for Wildlife (see, for example, this article on Caper White migration).

Dr Lambkin believes there just isn’t enough scientifically recorded information about these butterfly mass movement events to allow for the full picture. Why the Blue Tigers are all heading in one direction must, for the time-being, remain another of those wonderful mysteries of nature — to be watched and enjoyed.

Links

Ogre on the fence

How could you not like a spider with a name like Ogre-faced? I found this ogre, more commonly known as the Net-casting Spider (Deinopis subrufa), lurking on a fence facing a busy suburban street.

This is a female net-casting spider. Males are much thinner. The Queensland Museum reports that “At night, the female spider builds a brilliant blue-filled rectangle of silk which it swirls around passing prey with remarkable speed.”

‘In a bygone but more erudite society this spider was called the Retiarius (lit. “net-man” or “net-fighter” in Latin) after the lightly clad gladiator of ancient Rome who faced his more heavily encumbered opponent armed only with a cast net and trident.’ Rod Hobson

The Australian Museum tells us more about its net-casting abilities. “In order to have an aiming point, the spider often drops splashes of white faecal droppings onto the leaf or bark substrate over which it is poised. When an insect walks across this ‘target’, the spider plunges its net downward to envelop and entangle it. If successful, the spider silk-wraps the prey item, bites and paralyses it, and then feeds on it. Net strikes will also be made at flying insects that stray too close. An unused net is sometimes stored by hanging it on nearby leaves for the next night’s hunting, or the spider may eat it.”

Mystery of the clicks

The sounds of nature are always there, even in the city and suburbs, if you stop to hear.

Sometimes they are memorable, melodic noises. I remember lying in bed as a child in Brisbane in the dead of night listening to the cheerful call of a Willy Wagtail or the haunting, ‘mo-poke’ call of the Southern Boobook Owl. At other times the sounds are mysterious drones, clicks or whistles, all just part of the background of summer in the suburbs. Unless it’s a click that you’ve been trying to find the owner of for years.

The makers of many mysterious nocturnal noises lurk in a suburban backyard!

The makers of many mysterious nocturnal noises lurk in a suburban backyard! All photos R. Ashdown.

In our street on dusk after the first hot summer day, an all-enveloping, loud, continuous guttural rumbling fills the air. This is the call of the large, green Bladder Cicada (Cystosoma saundersii). These beautiful, large green insects are hard to find, given how loud and large they are.

Bladder cicada

Catching cicadas is a childhood pastime during an Australian summer. Some species sit warily high up on tall gum trees, taking flight at the slightest movement. Others, such as this Bladder Cicada, call on twilight and are well camouflaged. If detected, these cicadas will suddenly drop to the ground, hoping to avoid being caught.

Bladder Cicadas are found in closed forest and gardens on coastal Queensland and New South Wales. In males, the large, hollow abdomen acts as a resonant sound radiator, allowing the cicada’s song to carry long distances. In our suburb, the call of these insects on a summer evening can be deafening.

Most of the life of this cicada, like most species of this insect, is spent below ground as a nymph, feeding on the sap from the roots of trees. On  warm summer nights, nymphs leave the safe, dark earth, climb a tree or fence post and the adult cicada emerges from its brown skin, unfolding delicate wings that are pumped full of fluid as they unroll and harden. The shed skins, or ‘nymphal exuviae’ remain behind, clinging motionless and empty to a fence post, evidence of the adult cicada’s arrival above ground in the night.

Venation in a cicada wing.

Veins in a cicada’s wing.

The adult cicada usually only lives for two to three weeks. Males call to attract females, who fly to the male chorus and land within 50 cm of the male.The female produces a pheromone  which is distributed by wing-clicking. The male responds by changing to the courtship song, before moving towards the female and mating. The female cicadas lay eggs in the live branches of plants that are suitable for the larvae, which hatch and climb down below ground.

For many years, I’ve pondered a strange, intermittent clicking noise heard in summer in the suburbs of Brisbane and here in Toowoomba. The clicking was recently described by a naturalist mate, who had also heard them, as ‘like the sound made by two Aboriginal message or song sticks clacked together’. A perfect description. Advice from those who study insects and like stuff has pointed me towards another green cicada as the likely suspect — the  Bottle Cicada (Glaucopsaltria viridis). This cicada has a long, whistling sound on dusk, but is known to produce some intermittent clicking sounds during the day.

Bottle Cicadas are about 3 cm long. The male has an inflated hollow abdomen. They are found in south-eastern Queensland and northern New South Wales. Their main song is a continuous, monotonous whistle at dusk, between October and April.

It’s taken years, but I finally found one of these insects. While walking on dusk past a hedge from which I’d previously heard the mysterious clicking, I noticed a long whistling call emerging from all over the hedge. Closing in on one source of the sound, an insect flew down to the ground, where my faithful fellow-naturalist dog tried to eat it. I wrestled the insect from the dog’s mouth, and found that it was indeed one of these green cicadas. I had at last solved my personal mystery of the weird clicking sounds.

Bottle Cicada. Cicadas have two obvious, large, compound eyes, and three ocelli. Ocelli are three jewel-like eyes situated between the two main, compound eyes. It is thought that ocelli are used to detect levels of light and darkness.

Bottle Cicada. Cicadas have two obvious, large, compound eyes, and three ocelli. Ocelli are jewel-like eyes situated between the two main, compound eyes. It is thought that ocelli are used to detect levels of light and darkness.

Some naturalists are dedicated to investigating, and recording and analysing, the sounds of nature. Sid Curtis describes on the Nature Recordists forum his investigation into the clicking call of  Bottle Cicadas, using some specialist microphone and and recording gear:

Here in Brisbane the Bottle Cicada is common in our suburban gardens. Like many cicadas, the males all sing at the same time, thus making it difficult to locate any one individual. With just one’s ears, that is. Klas’s so excellent and highly directional Telinga mic and reflector make it easy. They sing at dusk: “Continuous and without apparent variation”, is how Dr Max Moulds author of the book Australian Cicadas, describes it. But that is not all.

During the day they have a very different and far-from-obvious call. Just a few (up to 5) short sharp ‘bips’ over a second or so. Then silence for several minutes. Also very effective in making it difficult to locate the insect by the sound. (And incidentally, using Peak LE software and a Mac computer, I have strung these bips together without spaces between them, and produced their continuous dusk song.)

To locate one during the day, play a recording of the continuous dusk song, and the cicada just has to join in. He won’t keep going for long after you stop the recording, but you can start him again. The dusk song of course is to attract females for mating. The song changes if a female arrives. I surmise that the intermittent day song is aimed at males — to enable each to maintain his personal space. I hoped to test this by concealing a small speaker fairly close to a male and playing a recording of the spaced-out day song. Unfortunately my garden is very small; I’d have to use the garden next door. This was a possibility but the house was sold and the new owners cleared the whole area — all trees and shrubs have gone, and there’ll be no cicadas.

But back to mechanical noise. At one stage someone used a motor-mower with
a whine of just the right pitch to match the cicadas dusk song. And they
joined in!

Now, I’ll need another mystery of the natural world to solve. Luckily, there are zillions more out there!

Aliens lurk in every hedge, cooking up bizarre sounds to intrigue us all.

Links:

Also see my earlier post on cicadas here.

Blue, red and green

Three images from guest photographer Brett Roberts.

Ravensbourne National Park. Photo by Brett Roberts.

Ravensbourne National Park. Photo by Brett Roberts. Click on an image for a closer look.

Brett, a colleague in the Queensland Parks and Wildlife Service, is a photographer who combines a technical mastery of the camera with an eye for arresting composition and abstract expression. Here are three sublime glimpses of the shimmering, ever-shifting patterns and colours of nature.

Fire, Girraween National Park. Photo by Brett Roberts.

Bushfire, Girraween National Park. Photo by Brett Roberts.

Reflections at the Cascades. Crows Nest National Park. Photo by Brett Roberts.

Reflections at the Cascades, Crows Nest National Park. Photo by Brett Roberts.

‘To take photographs is to hold one’s breath when all faculties converge to capture fleeting reality. It’s at that precise moment that mastering an image becomes a great physical and intellectual joy.’ Henri Cartier-Bresson, The Mind’s Eye: Writings on Photography and Photographers

‘Mysteries lie all around us, even in the most familiar things, waiting only to be perceived.’  Wynn Bullock

Cryptic dragon

A Southern Angle-headed Dragon (Hipsilures spinipes), photographed at the Goomburra section of Main Range National Park.

Southern Angle-headed Dragon, Main Range National Park.

The Southern Angle-headed Dragon is found in sub-tropical rainforests in south-eastern Queensland north to the Gympie area and in northern New South Wales. This small, well-camouflaged reptile likes to perch on the trunks of trees where light penetrates to the forest floor, such as at edges of creeks and tracks. Southern Angle-headed Dragons eat insects and arthropods, such as centipedes and spiders. In December, females lay up to seven eggs in shallow nests in clearings, and there is evidence of communal nesting. Photo R. Ashdown.

 An earlier blog post on rainforest dragons.