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The Blues; nature's trompe d'oeil #3

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This is the final instalment of my discussion and celebration of blue in nature - which in turn is part of a sporadic series on colour in the natural world. As foreshadowed, this one focuses on plants. Unlike in animals, blue pigments are quite common in plants - flavonoids, indigoids, phytocyanobilins and anthocyanins can all produce blue flowers. Anthocyanins are interesting in that they can produce red, violet or blue depending on the acidity of the cell sap - some gardeners alter soil pH to influence the colour of their hydrangeas. 

However it seems that structural blues in plants may be more prevalent than hitherto recognised; this article gives an interesting overview of what is - and isn't - known about it. As far as I can determine though, this has scarcely been investigated for Australian plants.

There is another aspect that I must mention too, in that it affects my choice of photos. I have trouble sometimes deciding if a colour is blue or mauve; my partner and I differ, sometimes significantly, in how we interpret these shades. The other side of this coin is that cameras are notoriously unreliable when it comes to reproducing blues accurately, and some of the pictures below look a lot less blue to me than I recall their subjects being!

Anyway, that's enough introduction; let's just celebrate some delightful flowers.

Tall Bluebell Wahlenbergia stricta Campanulaceae, Canberra, with pollinating wasp.
Insects see best at the short wavelength end of the light spectrum - yellows, blues, purples and on into the ultra-violet - so these are the colours of insect-pollinated flowers.
Wandering Sailor Commelina cyanea Commelinaceae, Murramarang National Park, south coastal New South Wales.
With no supporting evidence, the striking blue of this flower makes me wonder if underlying pigments are not being amplified by structural features.
Blue Pincushion Brunonia australis Goodeniaceae, north of Perth, Western Australia.
Dampiera stricta Goodeniaceae, Namadgi National Park, Australian Capital Territory.
This rare and threatened species appeared in good numbers on rocky slopes a few years after the intense fires of 2003; a couple of years later they had died back again.
Hand Flower Cheiranthera cyanea Pittosperaceae, Wee Jasper, New South Wales.
The common name refers to the oddly-positioned anthers (the genus name means 'hand-anther').
Narrow-leaved Squill Chamaescilla spiralis Anthericaceae, Esperance, Western Australia.
A delightful lily, which can grow en masse from pure sand.
Nodding Blue Lily Stypandra glauca Phormiaceae, Canberra.

Blue Tinsel Lily Calectasia grandiflora Dasypogonaceae, Moore River National Park, Western Australia.
One of those which looks bluer in my mind than it does in this photograph.
Smooth Flax Lily Dianella longifolia Phormiaceae, Canberra.
Blue Lechanaultia Lechanaultia biloba Goodeniaceae, north of Perth, Western Australia.
One of the most breathtakingly blue flowers I know; quite stunning.

And a few orchids....
Blue Fingers Cyanicula caerulea, Canberra.
Waxlip Orchid Glossodia major, Canberra.
Bluebeard Pheladenia (Caladenia) deformis, Alligator Gorge, South Australia.
Two sun orchids; Thelymitra media and T. ixioides, Ulladulla, New South Wales.
Mountain Beard Orchid Calochilus montanus, Canberra.
The shiny blue smooth plates on the labellum seem very good candidates for a structural blue,
formed by layers of cells over a dark background.
Tasman Flax Lily Dianella tasmanica, Namadgi National Park.
It seems that blue berries get their colour from a waxy layer scattering blue light.
Lastly, the article I mentioned in the second paragraph discusses some blue foliage at some length, though its purpose is not at all clear.
Bluebush Maireana sedifolia, Gawler Ranges, South Australia.
Here the blue is from a waxy leaf coating which helps protect from water loss in a harshly arid environment;
perhaps the colour is an incidental byproduct of this.
Lilly Pilly Acmena smithii Myrtaceae, south coast New South Wales.
The article referred to above discusses a multi-layer blue iridescence in the leaves of some
rainforest understorey species (which this small tree is), as a possible protection against unexpected high-intensity
light exposure in leaves not otherwise adapted to it.

A very silly song that I recall expresses the hope that "these pretty flowers chase the blues away". It's too corny and inappropriate to mention here so I won't...

BACK ON WEDNESDAY


The Song of the Butcherbird

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The song of the Pied Butcherbird Cracticus nigrogularis is without doubt my favourite bird song of all. If you click here you can enjoy it while you read the rest of this brief post. (Andrew Skeoch is unquestionably one of Australia's foremost wildlife recorders and you could do worse than go on to his site after you finish here; and no, I've only met him once, by chance, and he doesn't know me!)



A bold hunter, the Pied Butcherbird is a bird of the dry inland, one of the reasons for my passion for it. And for the next month, I'll be hearing it, and you won't be reading me, as we head up through central Queensland, across the Donohue and Plenty 'Highways' (no bitumen, lots of dust and corrugations) to Alice Springs in the central deserts, and ultimately home via the Andamooka Track and the Flinders Ranges, definitely heart country for me.

I'll doubtless come back with lots of material for future postings, so please don't forget me! I'll be checking in when internet access allows (ie not very often) and would be glad of your comments.

BACK ON TUESDAY 28 MAY

Desert Oaks; beautiful desert giants

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If I were to ask you to nominate Australia's most photographed tree, I wonder what you'd suggest? Perhaps the Cazneaux Tree (a River Red Gum in the southern Flinders Ranges, made famous by Harold Cazneaux's 1937 photograph The Spirit of Endurance, and rephotographed numerous times since)? Or maybe the Curtain Fig at Yungaburra on the Atherton Tablelands of north Queensland, a massive Strangler Fig visited by every tourist bus in the area, and there are many of them!
A segment of the Curtain Fig Ficus virens, Yungaburra, a massive tree.
You'll probably have other suggestions, but my bet is on a tree that most people don't even realise they're photographing. 

Every day hundreds of people gather in central Australia at set areas to watch the sun going down on mighty Uluru, previously known for a while to English speakers as Ayer's Rock. The viewing areas are extensive, so there's no real sense of crowding, and the tour buses use a different area from private cars. A couple of weeks ago we joined them. Here is a selection of photos, taken over a 40 minute period from before to after sunset - just five of 18 that I ended up keeping.





So, if every one of the people there on just that one evening took that many pictures - and many would have taken far more - that's thousands of pictures a day, and it's not peak visiting season yet.

And, you see the tree? I suspect that most photographers don't even really notice it. Here it is again closer up, the shots taken just 10 minutes apart - the light changes are truly stunning.


This tree - my nomination for the title of Most Photographed Tree in Australia - is a Desert Oak, Allocasuarina decaisneana. It is my favourite tree species of the Australian central-western deserts, limited to an area of eastern Western Australia, south-western Northern Territory and a tiny bit of north-western South Australia. They are the only casuarinas in central Australia, most of the family being near-coastal in distribution. (Some time ago the genus Casuarina was controversially split into two, creating the genus Allocasuarina based on minor differences.)

It has adapted to life in the sandy dune country, where spiny spinifexes (hummock grasses of the genus Triodia) dominate the understorey.
Desert Oaks, Chambers Pillar, Northern Territory.
Unlike many other casuarinas, adult Desert Oaks are largely fireproof, recovering from epicormic shoots in the crown; at the same time seedlings sprout in the wake of the fire.

Stand of Desert Oaks south of Alice Springs.
In the photo above the beautiful adult trees appear to be growing above another bottle-brush-shaped species, but this is an illusion. The seedlings don't resemble the adult trees at all.
Desert Oak seedlings, Uluru - Kata Tjuta National Park.
Close to the ground the young trees are a spiky tangle, resisting grazing. The crown doesn't form for years; during this time the emphasis is on sending a tap root deep into the soil. When it strikes ground water many metres down, the crown finally develops and the side branches wither. 

The timber is hard and heavy and was used by the desert peoples for tools and weapons but, perhaps fortunately, it doesn't hold its shape after cutting and drying, so wasn't harvested by European settlers.

The species name honours a Belgian botanist, Joseph Decaisne, who spent his working life - much of the 19th century - working in Paris, especially at the Muséum d'Histoire Naturelle, where he began as an apprentice gardener. He never visited Australia, though he described some species from French expeditions returning from there. He rose to become regarded as the leading French botanist of his time, though it is often said that it was his studies into fruit varieties which were his main achievement. It was the great German-Australian botanist Ferdinand von Mueller who honoured Decaisne with the name.

There are separate male and female flowers but, unlike in many casuarinas, they occur on the same tree. The seed cones are magnificent, and can be up to 10cm long.
Desert Oak seed cones.
One day I'll do a posting on casuarinas in general, but for today I wanted to focus on this one beautiful species. 

Meantime, do you have another nomination for most-photographed tree? I'd love to hear.

There will be more postings inspired by the wonderful arid lands we've just visited; thanks for waiting for me!

BACK ON FRIDAY

Goanna, Go!

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Australia has truly been described as the land of lizards, with central Australian spinifex hummock grasslands containing over 400 lizards per hectare, with over 40 species co-existing. They are both predators and prey in an ecosystem where the spinifex supports a vast biomass of grazing termites, which fill the role of antelopes in the African plains. The top predators - the lions if you like - in this system are goannas of the family Varanidae. They don't generally stoop to eating termites, but they eat many smaller animals which do. 
Sand Goanna Varanus gouldii north of Bourke, New South Wales.
This familiar species is found across virtually the whole continent, missing only from the far south-east and north-east.
Elsewhere in their wide range - across Africa and southern Asia - they are generally known in English as monitors, allegedly for their supposed habit of 'warning' of the presence of crocodiles. In Australia however (where varanids have reached the peak of their diversity) the British colonists, who certainly weren't herpetologists, confused them with New World iguanas; the quintessentially Australian 'goanna' is a corruption of that. However, we're a perverse lot, and some local species are still called 'monitors'...
Lace Monitor V. varius, Finch Hatton Gorge, near Mackay, tropical Queensland.
This is probably the best-known Australian goanna, being found right along the east coast where most people also live.
It's a big animal, up to two metres long, and can be a tad intimidating around camps and picnic areas.
It seems that the goannas are more closely related to snakes than to other lizards, though this is not universally accepted. One thing that goannas and snakes have in common, only recently recognised, is the presence of venom in the mouths of varanids (and iguana relatives), and other work proposes that this supports the idea of a common ancestor for all three groups. To date most of the work on this relates to the huge Komodo Dragon V. komodoensis of Indonesia; venom flows from glands between the front teeth into wounds made by the animal's ferocious bite. There have long been stories in Australia that goanna bites "never heal"; it was supposed that this relates to a diet that includes carcasses and poor dental hygiene, but there may be more to it than that. These venoms are relatively low-potency and slow acting; it seems that the large victim is simply patiently followed, perhaps for days, until it weakens.

Goannas and snakes (and at least some other lizards) make use of Jacobson's Organs, a pair of sensory organs located above the roof of the mouth; while not unique to goannas, they are particularly well-developed in them and are doubtless very significant. Chemicals in the air are transferred by the tongue to the organ via ducts; this sense (perhaps best thought of by those of us without them as 'smell-taste') appears to supplement scent.
Yellow-spotted Goanna Varanus panoptes, Bladensburg National Park, Queensland.
The forked tongue - another goanna characteristic reminiscent of snakes - flicks constantly in and out, 'tasting' the air.
This species is found across much of north-east and north-west Australia, but where the introduced poisonous Cane Toads have invaded, numbers have crashed. Fortunately for this individual (investigating our camp) the toads
haven't entered this drier environment.
The largest goanna that lived only left the scene some 40,000 years ago, well within the time of human occupation of Australia. Megalania prisca (sometimes called Varanus priscus) may have been up to seven metres long and weighed well over a tonne; I would not have argued the occupation of a campsite with that one! Moreover it is within the venom-bearing group, and lived long after that group split up, so would have probably been the largest venomous animal ever to live.
Yellow-spotted Goanna in camp, Bladensburg NP.

Goannas are now the top predators in most of Australia (leaving aside the recently-introduced Dingo); indeed it has been suggested - I hope in jest! - that marsupials don't need a very big brain to stay a jump ahead of a reptile... Indeed these reptiles show intelligence in locating and accessing prey; they dig out burrows, either of mammals or scorpions, and climb readily. For both activities, their enormous claws are extremely efficient.
Yellow-spotted Goanna, Bladensburg NP; note huge claws.

They are the bane of the lives of tree hollow-nesting birds, which will attack them fiercely, but often with little effect. Many species will also take to the trees when threatened; plenty of stories also tell of them running up the nearest tall object in such a situation, including a person, though first-hand accounts are harder to find...

Lace Monitor on ironbark, Pilliga State Forest, New South Wales.
They effortlessly descend head-first.

 
All lay leathery eggs; some seal them in termite mounds where the controlled temperature and humidity is perfect for them. There is now evidence that the female of these species returns at just the right time to break open the mound again and release the hatchlings. 

Goannas are an integral part of Australia, through every part of which they still swagger with an inimitable insouciance, and I for one am glad of it.
Sand Goanna, above, and Yellow-spotted Goanna, below.


BACK ON MONDAY




Of Dinosaurs, Marketing and Truth; Lark Quarry

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We were 100km south of Winton, in remote central western Queensland. As we sat and had lunch under the little shelter – even in autumn the temperature was well over 30 degrees – a dinosaur arrived to inspect us. It was small, quick, warm-blooded and feathered, like many of its direct forebears among the Theropod group of dinosaurs which perished in the aftermath of the cataclysmic meteorite strike some 65 million years ago.
Grey-headed Honeyeater Lichenostomus keartlandi, Lark Quarry CP;
a living dinosaur.
Coincidentally we had just come from inspecting with some awe a superb area of direct evidence of the existence of some of these Theropod ancestors, carefully protected in a purpose-built structure just metres away. This was Lark Quarry Conservation Park, gazetted in 1982 to protect the spectacular evidence, as it was interpreted, of the only dinosaur ‘stampede’ to be so far discovered, in the form of over 3000 fossilised footprints. National Heritage Status was applied in 2004.
Lark Quarry dinosaur site interpretive centre, set in a beautiful arid landscape.
Its forerunner was a large roof, erected in 1979 to protect the newly exposed dinosaur tracks.
When the Conservation Park was gazetted in 1982 a walkway was constructed above it to provide a memorable viewing experience. The superb visitors' centre opened in 2002 (and reopened the following year when an internal rammed earth wall, which collapsed almost immediately, was repaired!). It is jointly managed by Queensland Parks and Wildlife Service and Winton Shire Council, with advice from the Queensland Museum.
Today access to the footprints is only possible in the company of a trained volunteer guide, for a modest fee.


The world of 95 million years ago was a very different one from the one we enjoyed that day, walking a track through the stunted woodland and spinifex-covered ‘jump-ups’ after viewing the tracks.
The modern landscape is an arid one, dominated by hard-capped sedimentary 'jump-ups' covered with spinifex (spiny hummock grasses of the genus Triodia, which dominate 25% of Australia) above plains where Normanton Box Eucalyptus normantonensis, a shrubby mallee form, is the most common tree.
The wet forested swamplands that the dinosaurs inhabited are hard to imagine now.


Back then, deep into the Cretaceous but 30 million years before the sudden extinction of all non-bird dinosaurs, the land was dominated by forested wetlands, warm and humid with over 1000mm of rain a year. According to the understanding of those who painstakingly excavated, protected and interpreted it, the scene forever set in stone was played out when a large Theropod dinosaur (not Tyrannosaurus rexbut of its ilk) surprised a mixed herd of small Theropods and Ornithopods (the ‘other’ major group of dinosaurs, mostly herbivores which, despite their name – ‘bird foot’ – did not lead directly to modern birds!) at a waterhole. In the panic which ensued, the confusion of tracks of the small dinosaurs is overlaid by the massive footprints of the huge predator. The clarity of some of them is superb. 

The small dinosaurs are described as long-toed Skartopus (a Theropod) and short-toed Wintonopus (an Ornithopod). It is important to recognise that both species are known only from footprints (not an unusual situation with dinosaurs, the term for their study being ichnology); Skartopus is known only from Lark Quarry. Further, the big predator is the only evidence that large carnivorous Theropods occurred in Cretaceous Australia (though there had previously been some in the Jurassic).
The trackway from the viewing platform, a chaos of clearly identifiable tracks.
There are doubtless many more still covered by the surrounding rock, visible at the back.


The clarity of many of them seems remarkable;
to the left can clearly be seen the long-toed prints of Skartopus.

Here a massive footprint of the apparent pursuing predator overlays the smaller prints.
It’s a great story, and one which is worth a lot of money to the Shire, as a lot of people make the trek of 100km from Winton, and presumably many of them stay an extra day there to do so. The street rubbish bins in Winton are in the shape of dinosaur feet, and signs point the way to the Dinosaur Stampede. 

But... And isn’t there always a but? Things may not always be as they seem; science is an eternally ongoing process of investigating further, questioning the accepted, testing what has already been taken as given. And so it is with the Lark Quarry site.

The investigative heroes, or spoiling villains, depending on your perspective, are (then Ph D student) Anthony Romilio and his supervisor Steven Salisbury, both of the University of Queensland. It began with a publication in 2011, wherein they re-examined the big ‘predator’ tracks and concluded that in fact they belonged to a large vegetarian Ornithopod, similar to the famed Muttaburrasaurus langdoni, named for the nearby town of Muttaburra. This is not the first time it had been suggested that the tracks might be so explained, but no-one had previously done the detailed analysis.

This removes the anomaly (which certainly didn't represent an impossible problem) of this being the only evidence of a Tyrannosaurus-type in Australia at that time. It also led to the next question; if this was a harmless herbivore, why were the little ones fleeing? The appearance of an elephant doesn’t create panic among antelopes. So, Romilio and Salisbury, plus Ryan Tucker of James Cook University, looked again at the ‘stampede’ tracks, and concluded in January this year (2013) that they are no such thing. Worse, they decided that Skartopus didn’t even exist!

Their explanation, painstakingly studied and explained, is that this was a crossing point, used by many animals over a period of time. Some strides were simply too long for the size of the animal, which would be explained if they were ‘bouncing’ through water, especially downstream. The long-toed ‘Skartopus’ tracks were actually those of Wintonopus in relatively deep water, pushing along the bottom with their claws.There is a nice little animation here which helps explain it.
'Skartopus' tracks, now interpreted as being made by a buoyed-up Wintonopus pushing along the bottom sediments as it part-floated across the river.

Very similar swim-traces like these were made by different-sized dinosaurs, indicating that the water depth varied. The authors believe that the footprints represent not a single panicked event, but a period of days or even weeks during which animals either swam or waded the crossing, depending on its depth and their size, which ranged from that of a chook to an emu.
Wintonopus crossing the river, leaving the characteristic deep scratches in the sediment,
as illustrated by researcher Anthony Romilio, courtesy of Science Daily.

Is this definitive? Of course not, though it’s pretty convincing and to date hasn’t been challenged. Does this devalue the site? Again, of course not, it simply refines our understanding of what happened. It’s as close to a photograph of life in the Permian as we’re going to get and is of world significance. The only importance of the ‘stampede’ scenario was a marketing one. Sadly this has influenced some people to seek to suppress the science – always a sad situation – and some Shire representatives have instructed the volunteer interpreters not to mention the new evidence.

Even if this interpretation proves not to be the ultimate ‘truth’ about the site, it is a current truth and deserves as much air and light as the more ‘sellable’ one. Truth has a way of emerging though and commercial interests are unlikely to bury it for long. Better that it was told now.

And in that vein I must sadly accept that the little dinosaur which visited us at lunch that day probably didn’t have direct Theropod ancestors among the nearby track-makers after all. It was a good story while it lasted, but that is after all the nature of science. 

Don’t take my word for it though – go and see for yourself some time. And when you do, be sure to ask about this story; they need to know that we know...

BACK ON FRIDAY

The Lichen-mouth Honeyeaters; Lichenostomus

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In my last posting I featured, in passing, a Grey-headed Honeyeater that I only half-facetiously described as a small dinosaur. 

Perhaps by way of making amends, I thought I’d showcase today the genus that this species belongs to. Honeyeaters comprise the largest family of Australian birds (74 species, or over 10% of all Australian species); Lichenostomus is the largest honeyeater genus, whose 18 species represent nearly a quarter of our honeyeaters, including some of the most familiar ones. The name, meaning ‘lichen mouth’ comes from the Purple-headed Honeyeater L. cratitiusof the southern mallee woodlands, which has a curious little mauve wattle at the gape. I can’t you offer a picture of it, but I do have snaps of many of the others (of varying quality!) and I’d like to introduce them to you. 

Let’s give the Grey-headed a chance for a reprise appearance. Although not very familiar to city bird-watchers, it occupies a huge swathe of the arid inland, in sparse woodlands and hummock spinifex grasslands. 
Grey-headed Honeyeater L. keartlandi, in Grevillea wickhamii, Watarrka National Park (Kings Canyon), central Australia. The name commemorates George Keartland, a Melbourne Age photographer and typesetter who apparently held down the job mostly to finance his natural history interests, which included two collecting trips to northern Australia in the 1890s, where he collected the type specimen of this handsome bird.
By contrast, one of the commonest honeyeaters in the south-east is the Yellow-faced, abundant in coastal and mountain forests alike. In late autumn in Canberra flocks ranging from a few to hundreds pass noisily overhead on still sunny mornings for a few weeks, funnelling along the river corridors to destinations along the warmer northern coasts. In spring they slip back much more discreetly.
Yellow-faced Honeyeater L. chrysops, south coast New South Wales.
Another member is perhaps the most widely familiar honeyeater to any camper in Australia, especially along the inland stream lines dominated by River Red Gum Eucalyptus camaldulensis. The White-plumed honeyeater is gregarious, voluble and pugnacious. It’s something of a relief to get to the far north of Australia, where suddenly the White-plumeds give way to other, more sedate species along the creeks.


White-plumed Honeyeater L. penicillata, a name which compares the white plumes to a paintbrush.
Milang, South Australia.

One of those honeyeaters which replaces it in the tropics is the White-gaped honeyeater, whose cheery chewy calls in the pandanus thickets and streamside scrubs are a pleasant change from the White-plumed’s constant carping.

White-gaped Honeyeater L. unicolor, Darwin.

Another tropical lichen-mouth is the lovely Yellow Honeyeater, sometimes known as Bush Canary for obvious reasons. It is found only in north-east tropical Queensland.
Yellow Honeyeater L. flavus, Ingham, north Queensland.


At the other end of the colourfulness scale (in this genus at least) is an often overlooked bird which is nonetheless not uncommon in Canberra woodlands and along the east and south-east coasts. Fuscous Honeyeaters are something of a favourite of mine, perhaps in part because they do seem often to be forgotten.
Fuscous Honeyeater L. fuscus, Jerrabomberra wetlands, Canberra. This one was busily eating lerps, the sugary coating of scale insects which suck the sap from leaves. The insect wants the scarce nitrogen compounds, and to get enough sap for its needs it must disposed of unwanted sugars in the form of a shelter; these in turn attract birds, who favour both roof and inmate.

A rarer visitor here is the lovely Yellow-tufted Honeyeater, which turns up sporadically where native trees or shrubs are flowering; it is commoner nearer to the coast. The critically endangered Helmeted Honeyeater, the Victorian state emblem, is a sub-species of Yellow-tufted.

Yellow-tufted Honeyeater L. melanops, Jerrabomberra wetlands, Canberra.

The White-eared honeyeater on the other hand has a remarkable habitat range in south-eastern and south-western Australia, from coastal heaths to subalpine Snow Gum woodlands to the dry inland mallee scrubs, where I first met it. One spent much of last winter in our garden, favouring the big Banksia tree that dominates; I eagerly await its 2013 return.

White-eared Honeyeater L. leucotis, Jindabyne, New South Wales. A feature of this very handsome bird is its ringing melodic ‘chock’ call, like a guitar chord.


Another lichen-mouth shares its inland woodland and mallee habitats, but doesn’t follow it to the east coast (or Canberra); it does however reach the arid coasts of western South Australia and southern Western Australia. Yellow-plumed Honeyeaters can be abundant where eucalypts are flowering.
Yellow-plumed Honeyeater L. ornatus, Nundroo, far western South Australia. Like the Fuscous Honeyeater above, this one too was collecting lerps from the leaves, this time of mallee eucalypts. As for its name – well it is certainly ornate (I love that show-off yellow plume) but favouring one in the family with such a name can only lead to arguments...


Finally, one of the most head-scratching names ever applied to an Australian bird – the Singing Honeyeater. About the most I’ve ever heard it manage – and I’ve heard a lot of them – is a slightly peevish ‘prrrit’. Yet the great, and generally sober, John Gould, who named it, waxed lyrical about its singing prowess. Goodness knows what he was hearing (or imbibing). Don’t get me wrong – I love Singers, which I meet anywhere across the vast dry inland, as well as on the arid southern and western coasts, but it’s not for their melodies.
Singing Honeyeater L. virescens, eastern edge of the Nullarbor Plain, Western Australia. Gould actually called it sonorus, not realising that French ornithologist Louis Vieillot had beaten him to it by some decades with a name that means ‘greenish’. Maybe slightlycloser to the mark than ‘singing’.
We’ll end where we started, with the obliging Grey-headed Honeyeater feeding in the Watarrka grevillea. How could I refuse a bird that looks this menacing?

BACK ON TUESDAY



On These Days, 10 and 11 June; celebrating Portugal and John Stokes

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OK, it's cheating, but I wasn't here yesterday, and you don't really want to miss a good story do you? (And anyway it's still 10 June in some parts of the world as I type!)


10 June is Portugal Day. Portugal Day is unusual among national days in that it commemorates the death of a poet - Luís de Camões in 1580. He was responsible for Os Lusíadas, an epic poem celebrating Portugal's exploratory achievements (I've not actually read it, you understand). He knew something about his topic, having been shipwrecked in Indochina and (so the story goes) swimming ashore with the precious manuscript held aloft. Why his deathday? For the very practical reason that his birthday is unknown.

Portugal and Australia? Yes, indeed. The stories of the first maps to show 'Australia' are tangled webs indeed, and well beyond my limited expertise, but some of them from the 15th Century show a continent south of Java with surprisingly Australia-like features; the cartographers said that this was because information was gleaned from unnamed Portuguese sailors trading spices from the nearby Moluccas. This is not verified, but it's certainly plausible - the Portuguese were great sailors and map-makers. One of our iconic birds, the Emu, takes its name from the Portuguese Ema, signifying a crane (or any other large bird); more information here

Moreover, a very eminent Portuguese polymath gave his name to a very beautiful, and familiar, genus of Australian wildflowers.

Correa pulchella, Coffins Bay National Park, South Australia.
The genus is for Jose Francisco Correia da Serra.


Da Serra, born in 1750, was an abbé of the church who took a law degree in Rome. He was also an enthusiastic geologist and botanist who founded the Portuguese Academy of Sciences at Lisborn. In 1795 he fled to London to escape the inquisition, but managed to secure a position as secretary to the Portuguese embassy in England. He also did some very significant biological research there, became a fellow of the Royal Society and became acquainted with the great botanists of both England and France, including Banks, Cuvier and von Humboldt.
Correa lawrenceana, Kosciuszko National Park.


His liberal sympathies made his position at the embassy difficult, and he moved on to France. Here his research continued, and he facilitated significant cooperation between British and French scientists. At the Paris museum he described some Rutaceae genera - the family to which Correa, as well as citrus fruit, belongs - mainly from south-east Asia. When Napoleon invaded Portugal (and the Portuguese government shifted to Brazil), Napoleon ordered da Serra to write a letter supporting his rule of Portugal. He refused and went to the US in 1813, where he met Thomas Jefferson who described him as “the greatest collection, and best digest of science in books, men, and things that I have ever met with; and with these the most amiable and engaging character”.
 
Correa bauerlenii, Eurobodalla Botanic Gardens.


He stayed for nine years and in 1816 he was appointed Portugal's minister plenipotentiary to the United States. From the US he finally returned to Portugal in 1821, on the advent of a liberal government there. He died just two years later, a vastly respected scientist on both sides of the Atlantic – but barely recognised in his home land.
Correa alba, New South Wales south coast. An unusual Correa in not having the four petals fused into a floral tube.

The English botanist Henry Andrews honoured him with the name in 1798, while da Serra was living in London.

And now, as they say, for someone completely different.

John Lort Stokes was a naval officer who moved in exalted biological circles. He spent 18 years on the Beagle, including five sailing with Charles Darwin; later he succeeded the irascible Scot John Wickham as captain. I love the report that, exploring ashore on the Gulf of Carpentaria he wrote of ‘the exquisite joy of discovery’. He later commanded surveys in New Zealand and the British Channel. He was regarded as a genial fellow, and was promoted to an admiral – but only, as far as I can confirm, after his retirement...

I hope he was glad to have this very handsome dry country lizard named for him, in 1845 by, I'm almost certain, John Edward Gray, then Keeper of Zoology at the British Museum. Stokes (now captain) had been surveying in Western Australia a few years previously, and it is quite possible he collected the species from one of its two small isolated coastal populations there (it is much more widely distributed further east).

Gidgee Skink Egernia stokesii, Whyalla Conservation Park, South Australia.

Stokes died on this day in 1885; not a scientist of the calibre of da Serra, but I think geniality counts.

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When the Past Lives On

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I like to be reminded - and I think it's good for all of us - that we are here by merest chance at just this moment. Things could have been very different had we happened along even just a few thousands of years ago or hence. Such reminders abound in the rocks, including fossils such as the dinosaur footprints we talked about recently, or snapshots in stone of past conditions.
Fossil seashell, Morton National Park, New South Wales,
in a site that is now 50km inland and a couple of hundred metres above sea level.
Ripple marks laid down on ancient shoreline, Watarrka National Park, central Australia.
There are plenty of such stories to be told, but that's not my intent today. Rather I wanted to look at a couple of living examples, both from central Australia. 

I recently had the pleasure of finally getting to the renowned Palm Valley, 22km south of Hermannsburg community along a rough road, then a challenging creek bed. Here, along just two kilometres of creek bed grow the remarkable Red Cabbage Palms - remarkable because the nearest palms are some 1000km away, across country far too arid to support palms. 

Red Cabbage Palms Livistona mariae, Palm Valley.
It is 30,000 years at least since the great central salt lakes were permanently full and the inland rivers ran as the norm. We're not sure what the rest of the land looked like then - the rainforests were long gone - but it is quite plausible to suppose that palms survived in oases from an earlier even wetter time, and perhaps even the fruit were carried by people as food or trade items. 

Their survival  here is due to an unlikely combination of events. It seems to me that the sheet sandstone that makes vehicle access both possible and very rough is a key factor, acting as a basin for water running down through the porous sandstone of the surrounding hills. It is a remarkable, and remarkably beautiful, place, and one guaranteed to set any rational person thinking.
Sheet sandstone creek bed, Palm Valley.
(Some recent work suggests that the nearest relation is the Mataranka Palm L. rigida, 1000km to the north, from which it diverged only 17,000 years during the last arid glaciation, in which case human vectors seem the most likely explanation for its presence, rather than being remnant vegetation. The story is still to be resolved.)

Another ancient plant found in these inland ranges has a larger range than the palm, but this range still only represents a dot on the map of Australia. Cycads are far older, as a group, than the flowering plants (including palms); they evolved in lush forests and while some modern cycads have adapted to drier situations, they can't cope with deserts. Again, the sheltered gorges of the Macdonnell and George Gill Ranges have enabled them to survive long after their relatives disappeared for well over a thousand kilometres around - long enough for them too to have evolved into a distinct species. 
MacDonnell Ranges Cycad Macrozamia macdonnellii, Standley Chasm, West MacDonnell Ranges.
It is always something of a surprise - and delight - to come across them in the sheltered gorges and cooler east- and south-facing slopes. 

Another surprise is finding a fig, but Rock Figs too survive in the gorges, and even in the harsh world of the canyon edges. This one isn't limited to the centre, but is found in suitably sheltered situations from here north-west to the distant coast, though the centre represents its south-eastern limits. Its ancestors were rainforest inhabitants, as are most of its relations today.
Rock Fig Ficus brachypoda; Ellery Creek Big Hole, West MacDonnell Ranges (above);
Watarrka National Park, George Gill Range (below).

Time fascinates me, so doubtless we'll be exploring variations of this theme in times to come.

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Yellow, not so Mellow in Nature

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[This is another in a sporadic series of postings on colour in nature; the most recent one is here, from where you can find links to older ones, or you can find them all by clicking on Colours in Nature under Labels on my blog home page.]

Yellow, like red, is mostly worn to be seen. "Here I am! Come and share my genes!" or maybe "Here I am! Come and feed with me, we'll be safer together", or even perhaps "Here I am! Take the hint and leave me alone, or it might be unpleasant for you."
Yellow Warbler (or Mangrove Warbler) Dendroica (or Setophaga) petechia - this is a bird who has an identity crisis, though it doesn't know it! - Puerto Ayora, Galapagos.
Like most birds, this glorious and friendly little warbler derives its rich yellows from carotenoids in its diet - fat-soluble plant pigments which may come from leaves, fruit or seeds, or from insects which have eaten carotenoid-bearing plants.The same plant carotenoids may be utilised in different ways by different birds, so may appear as reds or oranges also.

Many birds have opted for yellow plumage - though most have it as part of the overall ensemble, rather than the dominant theme like the Yellow Warbler.
New Holland Honeyeater Phylidonyris novaehollandiae on Calothamnus sp.,
Cape le Grande National Park, Western Australia. The yellow wings are particularly prominent
when this abundant honeyeater flies out of a feeding bush; perhaps warning others of potential danger?
Eastern Yellow Robin Eopsaltria australis, Monga National Park, New South Wales.
Cinnamon-chested Bee-eater Merops oreobates, Bwindi Impenetrable Park, Uganda.
Colour is in the eye of the beholder, and I reckon this lovely bird's chest is yellower than any cinnamon I've met.
Gilded Barbets Capito auratus, Sacha Lodge, Ecuador.
A bird of the rainforest canopy, where yellow may be a good marker for others of its kind to see it.
White-browed Robin-chat Cossypha heuglini, Entebbe, Uganda
Black-chinned Mountain Tanager Anisognathus notabilis, La Paz de las Antpittas, Ecuador.
This species and the next live in the gloomy understorey of the tropical forests; again yellow is a way to enable
mates to keep in touch.
Western Violaceous Trogon Trogon ramonianus, Cerro Blanco Reserve, Ecuador.
 
The distribution of carotenoids in a bird's body is not limited to feathers however. Bills, legs and bare skin may also be carotenoid-yellow.

Choco ToucanRamphastos brevis, Rio Silanche Reserve, Ecuador.
Both feathers and bill contain yellow carotenoids.
Southern Yellow-billed Hornbill Tockus leucomelas, Etosha National Park, Namibia
In some species exaggerated exposed skin - particularly in the form of wattles - is used for display.
African Wattled Lapwing Vanellus senegallus Murchison Falls National Park, Uganda.
This species has opted for yellow bill, legs and wattles!
Uniquely among birds, apparently, parrots synthesise their own yellow pigment - psittacofulvin.

Yellow Rosella Platycercus elegans flaveolus, Berri, South Australia.
Formerly given full species status.
Superb Parrot Polytelis swainsonii, Canberra.
Superb Parrots spend a lot of time feeding on the ground in grass, where the yellow and red chin and cap stand out.
Very recently it has been recognised that Macaroni Eudyptes chrysolophus and King Penguins Aptenodytes patagonicus, with yellow crests and necks respectively, utilise a pigment never before seen in birds; to my knowledge it has still not been described. 

Other birds manufacture a different group of pigments again, the pterins, specifically to produce yellow eyes; these too seem not to have been widely studied.
Powerful Owl Ninox strenua, National Botanic Gardens Canberra.
Spendid Starling Lamprotornis splendidus, Entebbe Botanic Gardens, Uganda.
Other vertebrates do things differently again. Mammalian hair colour relies on melanins; pheomelanins produce red-yellowish colours, though rarely as bright a colour as some of the bird pigments produce.
Yellow-footed Rock-Wallaby Petrogale xanthopus, Flinders Ranges, South Australia
Sumatran Tiger Panthera tigris sumatrae, Adelaide Zoo.
In fish, frogs and reptiles, most yellow is produced by the presence of xanthopores within the skin, containing pigments, primarily pteridines, produced by the animals rather than acquired from plants.
Northern Corroboree Frog Pseudophryne pengilleyi, captive animal, Canberra.
One would suspect that this colour combination signals a poisonous defence.
Holy Cross Toad Notaden bennetti, Cunnamulla Queensland.
After rain thousands of these dramatic frogs emerge from burrows. There are no true toads native to Australia.
Yellow-spotted Goanna Varanus panoptes, Bladensburg National Park, Queensland
And that's quite long enough a posting for today, though it would have been easy to continue on. Instead I'll talk a bit about yellow invertebrates next time.

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Yellow in Small Scale

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Last time I looked at yellow colouring in vertebrates; today it's the turn of the 'little world', where of course most of the action really happens. Like birds, many insects use plant-derived carotenoids, though many other pigment groups, including anthraquinones and flavinoids, are involved. 
Yellow Monday Cicada Cyclochila australasiae, Nowra, New South Wales.
This is the yellow form of a species which can also be green - when it is called the Greengrocer - when a blue pigment is also present.
In some beetles - notably ladybirds - it seems that the yellow is carotenoid-based, but that it doesn't come from plants. However the beetles can't make it either, but apparently derive it from symbiotic bacteria.
Ladybird, probably Harmonia sp., Brindabella Mountains near Canberra.
Leopard Longicorn Beetle Penthea pardalis, Cooktown, tropical Queensland.
Possibly a similar story to the ladybird, but I doubt that the details of its colouring have been studied.
Sawfly larvae, family Pergidae, eating Snow Gum (Eucalyptus pauciflora) leaf, Namadgi National Park near Canberra.
I would tentatively suggest that their yellow is due to leaf-derived carotenoids. The yellow and black is almost certainly saying "I taste bad - eucalyptus oil, yuk! - leave me alone".
Yellow and black wasps are saying the same thing, though they're not relying on being unpalatable; their sting is a very effective reinforcement of the message. Their yellows are mostly xanthopterins, which are also responsible for animal urine being yellow. There are exciting suggestions around that in at least some wasps the xanthopterin is converting sunlight to electrical impulses across the cuticle, enabling extra activity during the peak of the day when other insects are avoiding the sun. The main work seems to have been done on the Oriental Hornet Vespa orientalis; I have no idea if others can perform the same trick.
European Wasp Vespula germanica (on chicken), Canberra.
This has become an environmental and social scourge since being introduced to Australia.
Spider-hunting wasp, Isla de Chiloe, Chile.
In some circumstances however yellow can be a most effective camouflage. I only noticed this little flower spider when it moved as I was interpreting the flower structures to a class group!
Flower Spider, family Thomisidae, probably Diaea sp.
National Botanic Gardens, Canberra. I have no idea of the origin of its yellow, though its purpose is clear.
 Butterflies and moths don't utilise carotenoids, unlike most of the other groups I've mentioned, but many take flavonoids from plant sources.
Butterflies, San Pedro area, southern Peru.

Moth, Limbe, western Cameroon.
 In the pierids (family Pieridae, including the familiar Cabbage White), dark colours are due to pigments strongly bonded to chitin in the wing scales, while bright ones - including yellow - are powdery on the surface of scales.
Large Grass Yellow Eurema hecabe (Pieridae), 40 Mile Scrub Nature Reserve, north Queensland.
Some butterfly groups however are more specialised in their pigmentation.The wonderful swallowtails, family Papilionidae, have their very own pigments, papiliochromes which are yellow or red-brown.
Papilionid, Manu National Park, Peruvian Amazonia;
showing off its papiliochromes.

I should offer at least a gallery of yellow flowers too to complete this mini-series, though it will be hard making a choice - yellow is a very popular colour in the plant world!

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Dingoes; Australian Wolves

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Most Australians would be bemused, to say the least, at the proposition that Australia is home to wolves, but detailed biochemical work has confirmed that the Australian Dingo is indeed Canis lupus (subspecies dingo), derived from a semi-domesticated wolf in Asia some 6000 years ago and brought here by Asian sailors not much more than 4000 years back.
Dingo near Windorah, south-west Queensland.
This is a classic 'pure bred' Dingo but in truth there would be very few Dingoes without domestic dog genes today.
It seems 'obvious' that indigenous Australians would have brought Dingoes here, but having arrived some 50,000 - 60,000 years ago, there is no evidence that the first Australians travelled back and forward from Australia to Asia, and no reason for them to have done so. Dingoes didn't arrive with a late wave of settlers, but with seagoing traders who regularly visited the north-western coasts in particular.

So, are Dingoes native or feral Australians? I've struggled with this one for a long time, but of course there are no rules as to when an animal becomes 'native'; my own feeling is that 4000 years is probably too short a time for everything to have fully settled into a new balance, but plenty would disagree. The extinction on mainland Australia of Thylacines and Tasmanian Devils - marsupial carnivores which the Dingo would have competed with and quite possibly hunted - took place since the Dingo's arrival. The timing is too close to be coincidental, as is the fact that both these big native carnivores thrived in Dingo-free Tasmania - isolated 8000 years ago at the end of the last glaciation, before Dingoes arrived - at least until European settlement.
Tasmanian Devil Sarchophilus harrisii, Adelaide Zoo;
they didn't survive the advent of Dingoes on the Australian mainland.
Their rapid spread throughout the continent was doubtless assisted by Aboriginal Australians, who regularly domesticated young Dingoes as hunting and camp companions. Dingoes readily adapt still to human presence when not persecuted.

Bold, intelligent and inquisitive, Dingoes have learnt to scavenge around campgrounds,
though they are regularly shot around homesteads and stockyards.
Redbank Gorge campground, Western MacDonnell Ranges, central Australia.
Our own most recent experience with a Dingo was not a happy one. Camped at beautiful Redbank Gorge in the West MacDonnells, we returned from a long walk to find that a Dingo had torn holes in our tent and ransacked sealed containers looking for food; it wasn't smelling anything, as all our fresh food was locked away in a gas fridge, and the rest was in screw top plastic containers which it bit into. I emphasise that this was a most atypical situation; in my long experience of Australian bush camping, the only animals I've known attempt forced entry to a tent are goannas, or (exotic) mice and (native) rats, when they are experiencing a population boom. (Though I'm told that in Tasmania Brush-tailed Possums and even Tassie Devils can be a camping challenge on busy walking routes.) The problem here was previous campers who'd ignored ubiquitous warnings (and common sense!) and indulged themselves by feeding this Dingo, and leaving before the consequences came to bite them. 
Dingo on beach, Fraser Island, Queensland.
This is an area where visitor numbers and Dingo numbers are both high, and problems have arisen, again generally originating with irresponsible visitors (generally not the ones who eventually suffer!).

Once found throughout the mainland, Dingoes have largely retreated from the populous south-eastern corner, where their appreciation of sheep flocks was not reciprocated. Elsewhere despite constant and ferocious programs of shooting, trapping and poisoning they are still common. It is not uncommon to see Dingoes - mostly individuals or pairs - trotting near roads in remote areas, and to hear them howling at night, as the packs stay in contact and gather to hunt. 

Astonishingly, in the 1880s a 5600km dog-proof fence was built to isolate the south-eastern sheep lands from the Dingo 'bad lands' to the north and west.
Dingo-proof fence, courtesy Wikipedia.
The indicative distribution of 'pure' and 'hybrid' Dingoes is overly simplistic.
It is still maintained, though in large areas feral camels are defeating the efforts. To a large extent it still determines the boundary between sheep and cattle country in the Australian rangelands.

As pack animals hunting prey larger than themselves, Dingoes now fill the niche occupied by wolves (unsurprisingly!) in Eurasia and North America, and Cape Hunting Dogs in Africa. Their main large prey is various kangaroo species, and wombats in the south-east, though almost any smaller animal can be taken. They are probably important regulators of kangaroo populations, and seem to play a role in controlling rabbit and fox numbers where Dingo populations are healthy.

To my surprise, I've found myself coming to the view that, even though the Dingo is a recent arrival, it does play the role of top mammalian predator in the absence of the original ones, and should probably be permitted to do so to assist in control of excessive numbers of kangaroos and some pest species. I don't expect this view to meet universal acclaim however...

Regardless, this is a beautiful animal, now an integral part of the Australian landscape, doing what it does very well indeed. 

Dingo, West MacDonnells.
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On This Day, 27 June; John Latham's birthday

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By the end of the 18th century, John Latham was widely regarded as the greatest ornithologist of his age. I'm unconvinced by that, but there is no doubt that circumstances alone ensured that he will always have a place in Australian ornithological history. He was at the height of his influence when bird specimens were flooding back from Australia (and elsewhere), ensuring that many of them passed through his hands; he was also hard-working and committed to his task.

John Latham, courtesy Wikipedia Commons
Born in London in 1840, he became a successful English doctor, but his passion was always natural history and especially ornithology. Sir Joseph Banks lent him many drawings from the Cook expeditions - many of which Latham promptly copied, and in many cases he used these copied sketches as the basis of scientific descriptions, with predictable results. He also received skins, though it was difficult to get them through the tropics intact, hence the significance of the drawings. The collection of botanist Alymer Lambert was also available to him, including works by various colonial artists including Thomas Watling. 

Even before this however he had been elected a fellow of the Royal Society in 1775 and in 1788 was a moving force behind the formation of the immensely influential Linnean Society. His first great opus was the General Synopsis of Birds, published in six volumes from 1781 to 1785, in which he published the first descriptions of many Australian birds. However his great weakness was his failure at this time to appreciate the importance of the Linnaean system of unique binomial scientific names; basically he regarded Latin as foreign nonsense and couldn't see the point of it to an English scientist! One might then see an irony in his championing of the Linnean Society, or perhaps it was by way of atonement.

Glossy Black-Cockatoo Calyptorhynchus lathami, Nowra, New South Wales.
This tribute to Latham was paid by Coenraad Temminck, an eminent Dutch ornithologist, a generation younger than Latham; indeed when he named this magnificent - and now threatened - cockatoo in 1807, he was still only 29.
By 1791 he had realised his error and did adopt the system in his Index Ornithologicus, where he assigned Linnaean species names to his early idiosyncratic vernacular descriptions. By then however many of them had already been made invalid by others who had tidied up after him, applying their own names. Not all however, and many of Australia's most familiar birds bear the epithet Latham, indicating his authorship - Emu, Black Swan, Wedge-tailed Eagle, Willie Wagtail, Australian Magpie and some 50 others.

His later work A General History of Birds (1821-1828) was another huge undertaking. Throughout, he was a victim of the sheer volume of material cascading into the ports and the need to work often from drawings. Crucially, he had no familiarity with the birds in the wild, so he not infrequently described males and females, or young birds, as separate species, even within the one volume.

Swift Parrot Lathamus discolor, Canberra. Another threatened parrot species, whose genus was named for Latham by a French ornithologist and polymath, René Lesson, in 1830. It is the only species in this genus.
By our standards his perceptions of bird relationships were somewhat random; he lumped many unrelated Australian species as 'creepers', 'warblers and 'manakins'. However it was Latham who first applied the name honey-eater to Australian species, though for him it was a wide net indeed, encompassing bee-eaters, robins, whistlers, bowerbirds and whipbirds - plus some honeyeaters...

We ought not to be too judgemental however; the material available to him, the tools for studying it, and the communications for exchange of ideas, were all more rudimentary than we can imagine. By the time he died in 1837 aged 96 the world had changed - and he had played no small part in that.
Australian Brush-turkey Alectura lathami, (in rain!) Chichester State Forest, New South Wales.
This time the honours were done in 1831 by John Gray, a zoologist at the British Museum in London,
not long before Latham's death.

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An Arid Land Botanic Garden

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Port Augusta, at the head of Spencer Gulf in South Australia, is a place where you need to make a big decision if you're coming from the east. You can turn right and head north straight through the middle of Australia for nearly 3,000 kilometres to Darwin on the north coast, or you can keep heading west for a more modest 2,400 kilometres to Perth. Personally I find each option almost irresistible, though often neither is very practical. 
Port Augusta's location, at the end of the red arrow.
However even if I'm not doing such an epic journey, whenever I go there I do head just a few hundred metres north along the Stuart Highway to one of my favourite botanic gardens. I have a few of these, and they have featured as a sporadic series on such gardens in the course of my blog. The most recent can be found here, with links further back; or you can just look up Botanic Gardens under Labels elsewhere on this page.
Entrance from the Stuart Highway, on the northern outskirts of Port Augusta.
(Looking into the morning sun - sorry!)
This is not in any way a conventional botanic garden (which of course is one reason I'm featuring it!); it covers some 200 hectares, much of which protects an important example of good quality arid vegetation. This comprises chenopod shrublands (saltbushes and bluebushes) with scattered trees, notably the beautiful wattle called Western Myall.
Old Western Myall Acacia papyrocarpa in chenopod shrublands, Arid Land Botanic Gardens.
These trees are said to live for perhaps a thousand years.
The story of the gardens began back in the late 1970s when the Port Augusta Superintendent of Parks and Gardens, John Zwar, undertook a study tour enabled by a Churchill Fellowship to examine dryland horticultural practices overseas. Enthused, he returned and proposed in 1981 that the local Council support the establishment of an arid lands garden; there were none in Australia then, though work was underway on the Olive Pink Botanic Garden in Alice Springs, which will feature here in the near future. The state-run Adelaide Botanic Gardens offered its valuable support, and even more importantly the public got enthused by the concept. (I'd just left South Australia then, so missed much of the excitement.) It was a long hard slog, and it wasn't until 1996 that it opened to the public, but I can't imagine there's anyone who doesn't think it's worth it.

Access is by road, though there are walking tracks both in the 'wild' area and the planted gardens around the visitor centre. I generally drive right across the site first, soaking up the ambience and checking what birds are flying around, to the splendid view across the head of Spencer Gulf to the superb Flinders Ranges, which feel like heartland to me.
From Red Cliff lookout, with samphire flats below, fringing mangrove stands (these Grey Mangroves Avicennia marina represent an isolated population and are among the most southern in Australia - not as far south as those remnants near Adelaide and Melbourne however). Across the Gulf are the Flinders Ranges.
 In the midst of the plain, in a small stand of Western Myall and Sandhill Wattle Acacia ligulata, is an unexpected bird hide, featuring an artificial watering point.
The hide above, and the view from it (to the right of the top picture) below.


A variety of arid land birds can appear, but Singing HoneyeatersLichenostomusvirescens are pretty reliable.

Singing Honeyeaters enjoying the facilities.
Other bush birds are likely just to come and investigate; this female White-winged Fairy-wren
Malurus leucopterus almost certainly doesn't drink, getting her liquid requirements from her insect meals.
 From here too, the well-designed visitor centre, with its extensive plantings of Australian dryland plants, appears as a cluster of shrubs and low trees to the west, near the highway.
The visitor centre, visible only in glimpses among the plantings, in the vast plain with the low hills of the Hummocks behind. (Actually I've always assumed that these are a northern extension of the Hummocks, but someone might be able to advise me of a local name.)
The picnic areas and plantings around the centre are delightful.
Plantings around the carparks (above) and one of the picnic areas (below).

A feature of a courtyard is one of my favourite plants, the state symbol of South Australia.
Sturt's Desert Pea Swainsona formosa.
Green Rattlepod Crotolaria cunninghamii; a striking pea of the inland red dunes.
Halgania cyanea Family Boraginaceae
One of the garden's prides is a superb collection of Eremophilas - emu-bushes, or poverty-bushes, whose apparent delicacy belie their incredible toughness, as they survive in some of the harshest parts of the continent. Emu-bush reflects the belief that seeds must pass through an emu's intestine to germinate, thought that is demonstrably untrue for many species. They are now generally regarded as being in the family Scrophulariaceae, though until recently they were placed in Myoporaceae.
Granite Eremophila Eremophila platycalyx, from the granite country of central Western Australia.

Eremophila stenophylla from south-west Queensland.
Next time you're passing through Port Augusta, do yourself a serious favour and spend at least an hour at this very special garden.

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That Benighted Parrot

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Really there's only one natural history topic in Australia this week; the presentation of the first photos ever taken of a living Night Parrot at a remarkable extravaganza in a meeting room at the Queensland Museum. 

I have hesitated long and angstfully before committing myself to this posting - so much has already been said that it's doubtful there's more that is useful to be written, and the whole issue is fraught with cross currents. On the other hand I've been challenged at home, quite justifiably, to explain my apparent curmudgeonliness about the whole issue (curmudgeon?! me?! never - grumph...). And in truth when I tried to, I found myself uncertain. So, here goes.

OK, some background. The Night Parrot Pezoporus occidentalis has almost mythical status, having probably only been seen by a handful of living people. As you would expect, it is essentially nocturnal, and its habitat is essentially Spinifex (or Porcupine Grass) Triodia spp. hummock grassland; in South Australia at least its favoured sites seemed to be stony rises. So far so good - until you realise that 25% of the whole of Australia (ie almost two million square kilometres) is dominated by spinifex... 

Spinifex-covered hill, Gawler Ranges. Maybe there's a Night Parrot behind one of the clumps...
It was described by John Gould in 1861, from a specimen from "the interior" of Western Australia. Subsequently he was delighted to discover that Ferdinand Mueller had obtained a live one from the Gawler Ranges in South Australia, and had sent it to the London Zoo, where Gould examined it. For much of its shadowy history, the Gawler Ranges were a hotspot for the parrot. Indeed, at one stage I knew of 17 skins, of which 12 were from South Australia and 10 from the Gawlers; I understand that the latest count of museum specimens is 24. Local accounts described it as abundant, but this might simply have reflected a time when shepherds were on the ground to see birds flushed by the sheep. From the 1880s fencing was introduced, which led to the demise of the shepherd and of Night Parrot reports. It may well be that increasing Dingo numbers (without shepherds to control them) were affecting the parrots, but it is impossible to be sure if the issue was less parrots or less observers.
Night Parrots from John Gould's Birds of Australia.
courtesy National Library of Australia.

Certainly, as the 20th century progressed, reports slowed to a trickle. The excellent South Australian Museum ornithologist Shane Parker saw a group of Night Parrots in northern South Australia in 1979, by searching on camels which enabled him to sight them well ahead. Other accepted sightings (six of them) cover a huge arc of Australia from the Pilbara in the far west to central Queensland; these include two dead specimens (a road kill, and a bird which flew into a barbed wire fence) in Queensland. So, there was no question that they are out there, but how to find a scarce bird which is reported to spend its days in tunnels under spinifex, sealed with bitten-off stems?
Shaded area represents historical Night Parrot range; recent sightings as red dots.
Gawler Ranges at end of blue arrow.
Courtesy Wikipedia Commons.
Enter controversial bird guide and entrepreneur John Young, and the whole story becomes a little surreal. I have not tossed off 'controversial' lightly. In the 1970s he sensationally declared that he'd found a breeding population of Paradise Parrots in north Queensland, well outside the known range - or I should say 'former range', because there have been no confirmed sightings since 1922 and it is officially extinct. No-one else ever saw the birds (though he showed a select group of three the purported nest, a hollow in a termite mound). Startlingly he claimed (confessed?) to have taken six clutches, a total of 31 eggs for unspecified purposes, though they have never turned up in any museum collections. He seemed to have lost interest in the birds, as there was no apparent follow up. The eggs, if genuine, would have commanded vast amounts of money in the black market; in this case I can only hope he was lying.

In 2006 came another dramatic claim - a new species or sub-species of Fig-Parrot from the rainforested ranges of the south-east Queensland-New South Wales border, with photographic evidence. Given that it was within the range of sub-species Coxen's Fig-Parrot, it could hardly have been another sub-species, so another species was implied (there is only one recognised). Where Coxen's has a red brow, this bird had a blue one. In addition to the photographs, Young claimed to have taken pin-feathers from chicks for DNA analysis. Everyone, including the Queensland government, was very excited. In the event the photos were examined by a scientific photographic expert at the Royal Melbourne Institute of Technology University, who declared that the areas of image containing the very features which made the bird in the image unique were, to use a technical term, dodgy. Remarkably, Young claimed to have deleted the originals! And the promised pin feathers apparently went the same way, because they never appeared.

So, when Young bobbed up again, inviting people to a presentation at the Queensland Museum (in a hired room) at which he promised to show photographs and video of Night Parrots somewhere in western Queensland, there was some disquiet. In the event only six seconds of the video were offered, but the photos were apparently incontrovertible this time. (I wasn't there, but I know people who were.) Some of Australia's most eminent bird people, who would certainly known of Young's form, were convinced, which is good enough for me. It seems that fears based on the boy who cried wolf (dingo?) were this time unfounded.

Quite properly he is not divulging the location. More disturbingly there are signs that he doesn't intend to let any professional scientists or wildlife managers in on the secret either. Since the previous incidents, relations between him and government people have been somewhat frosty. Indeed, he is talking about raising up to $3 million from the private sector to prepare a management plan. Whatever Young may be he is not a scientist, and to my knowledge has never written a management plan; on the other hand there are scientists already employed to do just that, with extensive experience and expertise. 

Worryingly to me, one contact who was there reports that the 'white shoe brigade' was out in force. This is a reference to a group of Queensland Gold Coast property developers in the 1980s with powerful and wholly improper links to the state government. Is this where he's hoping the money will come from, and why he declined to show the video? It could worth quite a bit if offered as an exclusive. But of course I could be misreading the situation entirely and my contact may have simply misidentified a group of birders wearing suits and tennis shoes.

So why my slightly underwhelmed reaction, which surprised even me? Part of it is that I'm not taken by surprise, in that I've long taken an interest in the parrot, and have never doubted it's out there - the regular, though sparse, records make that impossible. So hyperbole comparing the very existence of it as being equivalent to finding a Thylacine or Elvis (it's true, someone did!) is a bit silly. Nor do I accept that there are only a very few hundred - or less - birds left, based on the few records. Those records span a couple of thousand kilometres of remote harsh country, and I've discussed the bird's very uncooperative behaviour. Of course we must adopt the precautionary principle and assume it is very rare, but I'd not be surprised if the opposite were found to be true; if the bird is living right across that range that means a large and well-buffered population.

I'm also very nervous about the way it's being kept from the people of Australia - not the location, that's essential, but everything else. The photos are made exclusive to The Australian, a notoriously right-wing News Limited paper whose only contribution to conservation in the past has been to attack it. The only access to the photos for the rest of us (via News Limited) is via a hefty fee 'with conditions'. This bird is no-one's private property, no matter how much effort and skill went to locating it. And there, I think, is the nub of my problem; the story ought to be all about the parrot, but it's somehow been shoved aside into a support role.

Nonetheless, just about everyone in Australia has now heard of it, which can only be good. We all await to see how the drama will play out; my big hope is that other populations are confirmed soon, preferably in a national park and by someone else. But what do you think?

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Puñihuil: penguins - and much more!

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After the domestic dramas of last week (and my Night Parrot posting attracted more interest in a few days than anything else I've written!) I thought it was time to focus on Somewhere Completely Different. And while Puñihuil is in the southern hemisphere, it couldn't be much more dissimilar to the arid desert home of the Night Parrot. For a start, the island of Chiloé is lush and wet; while much of the Night Parrot's world gets well under 250mm of rain a year (and it is very irregular), Chiloé gets close to ten times that - reliably! At 42 degrees south it is about the latitude of Hobart (for those who know Australia), it can be very cold, and its west coast faces the mighty Pacific, so winds are a fact of life. 
Chiloé indicated by the red arrow.


Some 25 kilometres south-west of the town of Ancud lies the little sandy bay of Puñihuil, with volcanic islets just offshore, accessed by a narrow winding country road (though perfectly safe and comfortable).
 
Puñihuil indicated by red arrow.

It is the little islets which are the main attractions, supporting important seabird nesting colonies which are both easily accessible to people wanting to view them, and largely safe from people going ashore. 
Puñihuil islets from the cliffs above the bay.
Photo courtesy Wikipedia; somehow in five visits I've omitted to take this shot!
The beach at Punihuil, with Kelp Gulls Larus dominicanus overhead.
The seafood restaurant at the end of the beach is also a feature!


When I first went there in 2006, boat trips from the beach to view the wildlife were run by the Alfaguara Project, dedicated to marine conservation (and especially Blue Whales). Since then the Project has worked to coordinate local tour operators - including the local fishermen - to run the tours cooperatively, thus helping their incomes and giving them a greater incentive to protect the values of the bay. Since 2009 the number of visitors permitted daily is capped, to further protect the animals.
 
Boat trip on the bay - a very calm day! When I first went, trips were run in inflatable zodiacs,
but the embarkation and landing are still 'wet'.


I mentioned the penguins as an attraction, but the key point is that two species breed together there; this is the only place where Magellanic Penguins Spheniscus magellanicus (a cold water species found as far south as the Gulf of Magellan and the Falklands) are found nesting alongside Humboldt's Penguin S. humboldti, here at the southern limit of its range, which extends north into the tropics in Peru. Nonetheless, it is a penguin, and it can only live in the tropics within the cold Humboldt's Current.
 
Magellanic (above) and Humboldt's (below) Penguins, Punihuil;
please bear in mind that all these shots are taken from a small boat in heavily swelling seas!
While very similar (and closely related), Humboldt's has only one breast ring, while Magellanic has that plus a collar.
 



Another feature is the pairs of lovely Kelp Geese Chloephaga hybrida, also found from here south on wild rocky shores. These South American 'geese' are in fact apparently most closely related to the shelducks (though at least one of my Chilean birding friends sees that as something of an affront!).
 
Strongly dimorphic, the male Kelp Goose is white, his mate almost black.


Another fascinating and very South American group of ducks is also in the shelduck group (though this relationship is currently being revisited), and is also found at Puñihuil. The steamer ducks are so-called from their habit of churning up the water in powerful courtship rushes; two of the four species are flightless, and here was my first encounter with the fascinating Flightless (or Fuegian) Steamer Duck Tachyeres pteneres, a powerful swimmer at home among the rocks and sea-swells.
The almost ridiculously small wings of the Flightless Steamer Duck are evident here.

Additionally four cormorant species breed here.

Imperial Cormorants Phalacrocorax atriceps (left) and Neotropical Cormorants Phalacrocorax brasilianus (right), Punihuil. Imperials are found south to the Antarctic Peninsula, while Neotropics range from the Gulf of Magellan to the Amazon basin.
Rock Cormorants Phalacrocorax magellanicus are striking marine cormorants
found all along the southern coasts of the continent.
Red-legged Cormorants Phalacrocorax gaimardi are surely among the most beautiful of all cormorants; sadly they are also one of the scarcest of South American cormorants, though doing well on Punihuil.
(And I did mention it rained a lot here!)
Southern Giant Petrel Macronectes giganteus on unusually flat seas, Punihuil.
The tubular nostrils that are a feature of this major seabird family are very evident here.


Finally, there is one star of the show that isn't a bird. Marine Otters Lontra felina are rare almost everywhere, but there is a small and apparently stable population at Puñihuil. These are not to be confused with Sea Otters Enhydra lutris, a much bigger animal of the north Pacific. Lontra is a genus of American river otters, of which only the Marine Otter has taken to the sea; and from my observations at Puñihuil it  has done so very well indeed. It will emerge from the surf with a crab or other prey, and effortlessly skip onto the rocks to eat it.
Marine Otters, Punihuil, hunting (above) and dining.
 

Chile is an overlooked part of South America by many visitors. That, in my opinion, is a mistake. Chiloé, in turn, isn't on the route of most of those who do get to Chile - also a mistake, though the general absence of tourists means it remains generally unspoilt, so maybe I should keep quiet! And Puñihuil- well, if I've not yet persuaded you of its charms, I should probably give up this blog!

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Trapping Desert Water; mulga and devil

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To survive in an arid land where it might not rain meaningfully for years requires strategies. Many larger animals are nomads, following the rains across the landscape; Red Kangaroos and many desert birds do this. Many smaller ones escape into burrows, even going into a torpor until the day is right - desert frogs are specialists, spending most of their life dozing in a muddy cocoon while waiting for the rains. 

Plants don't have that option - though many actually do something similar, surviving the dry times as a buried seed, and sprouting and flowering quickly when the rains come. Trees don't have this luxury - it takes too long to grow to maturity and flower - and in Australia none is more typical of the inland vastnesses than the Mulga Acacia aneura, whose woodlands dominate an astonishing 20% of the huge country, well over 1.5 million square kilometres.
Mulga plains to the horizon; from Chambers Pillar, Northern Territory (above)
and near Quilpie, south-west Queensland (below).


The red soils in both photos above are typical of the mulga lands, ancient leached infertile material eroded over vast periods of time from old ranges, now gone entirely or ground down to their bases. Mulgas, like all acacias, can deal with the lack of nutrient in the soil with the help of colonies of symbiotic bacteria in lumpy nodules on the roots; these bacteria can convert atmospheric nitrogen directly into soluble salts that the plant can use. No plant can perform that trick unaided. 

Fighting for the scarce rains is another matter however, and Mulga is an excellent fighter. The phyllodes (modified leaf stems which are better at conserving water than true leaves, a useful trick by many species of wattles and apparently some peas) are held vertically, to reduce overheating; the silver-grey colour is another heat-reducing factor.
Flowering Mulga near Windorah, south-west Queensland; it takes a reasonable water
supply to allow a tree to flower on soil like this.
Note the erect foliage.
However, this erect foliage plays a role in water harvesting as well, in conjunction with the typical Mulga form, which is like an inverted cone.
Mulga and spinifex on sandstone, plateau above Palm Valley.
This form is an excellent one for trapping rain, which is directed down phyllodes and along branches to the ground near the base of the tree - in the case of a large tree, to within 50cm of the base, closer for younger plants. In this way a 25mm rainfall can deliver the equivalent of 150mm of rain to the Mulga's roots! A Mulga tap root can go down for metres to access deep cool moist soil, where the water it has harvested can be stored. In addition there is a net of shallow roots stretching at least to the diameter of the canopy; I've heard it said that a 10cm sapling can have a root spread of three metres. There's not much future for plants growing under a Mulga's canopy!

One animal, also a truly deserving symbol of the Australian drylands, also uses its structure to bring water to where it can absorb it - which in its case means its mouth, rather than roots!

Never was animal more inappropriately name - both in the vernacular and scientifically - than the gentle utterly harmless Thorny Devil Moloch horridus. Moloch was a particularly unpleasant god of the ancient middle east, who required child sacrifices. 'Harmless' might be contested if you're a small ant however, as the 10cm long lizard can scoff up to 5,000 of them at a time; perhaps it was an ant who named it. With its upcurved tail, slow rocking gait and rose-like thorns it is a truly odd-looking little animal, found right across the dry inland.
Thorny Devil, Alice Springs Desert Park.
One of its most remarkable characteristics though is not readily visible without closer examination. Its whole body is covered with a network of fine canals, arranged so that any moisture landing anywhere on its skin permeates slowly but inevitably to its mouth. This may be from rain, or dew, or just standing with a foot in a puddle! However none of these water sources would seem to require such an elaborate mechanism; in fact the system really comes into its own when there is no surface water, but simply moisture in the air. Then the thorns pay their way - water droplets condense on their tips, and end up via the skin channels in the lizard's mouth.

Two remarkable strategies for survival in a very harsh land. Isn't it a wonderful world??

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On This Day, 16 June; Charles Sturt died

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On this day in 1869 a man regarded as a hero of Australian exploration died in England. There were times in his life when it seemed as though his woeful lack of aptitude at politics and financial management might overshadow his other achievements, but at the end he was widely and respectfully consulted on Australian issues - these included the preparations for Augustus Gregory's successful Northern Australian Exploring Expedition of 1854.
Sturt's, or Thargomindah, Nightshade, Solanum sturtianum, Broken Hill.
Named by Ferdinand von Mueller, perhaps the greatest of all Australian botanists,
in 1854, just after Sturt had left Australia for the last time.
Sturt was born in Bengal, to a judge employed by the East India Company (in those days it apparently didn't seem at all inappropriate to retain your own judges!). Presumably it didn't pay very well, as there wasn't enough money for Charles to go to university in England; as was fairly normal in such circumstances he joined the army instead, seeing action in Spain and Canada and serving in occupying forces in Ireland and France. At the age of 32, still a relatively lowly captain, he landed in New South Wales where he was appointed military secretary to Governor Darling, and thus met, and was inspired by, established explorers such as Cunningham, Oxley and Mitchell. His first expedition, in 1828, along the Macquarie, Castlereagh and Darling Rivers in a fierce drought summer, set the tone for future such work in three ways. These were that there was little of importance to the colony in the lands he traversed (his Murray trip later was the exception), and his care for, and courtesy towards, the men under him - and Aboriginal people he encountered - was exemplary. Additionally, he was a meticulous collector of specimens for science along the way, which of course is a major qualification for him being the subject of today's posting.

The following year he undertook what was to be his most successful expedition, and one which made his name. They followed the Murrumbidgee to its junction with the Murray, which he named, not realising that Hume and Hovell had already called it the Hume well upstream; actually he had a pretty fair idea, but the governor had expressed his wish to have something significant named for the British Secretary of State for the Colonies. 
Junction of the Murrumbidgee (opposite) and Murray Rivers.
Sturt and his party were the first Europeans to see this impressive confluence, in 1829.
They proceeded in a whale boat, which they had carried in sections, for another 1200km to the sea, which the river reaches having flowed through the mighty Lake Alexandrina. 
Mouth of the Murray, near Goolwa, South Australia.
Currently it is open, though for most of the last decade it has not been.
 Then, living on flour and parrots, they rowed back against the flood... The glare rendered him blind for months afterwards, but he was granted land near where Canberra now stands. Even more importantly to him, he was famous and respected. However his lack of business nous let him down, and he had to turn to pioneering a route along the Murray by land to overland cattle to the hungry new colony of Adelaide. 

Turpentine Bush Eremophila sturtii, found across much of arid Australia.
Named by the great Scottish botanist Robert Brown, who Sturt asked to describe his collections form his 1844 expedition.
He moved to Adelaide, but again things didn't go well for him, and in 1844 at the age of nearly 50 he undertook one last epic expedition. Encouraged by stories he'd heard when he first arrived, he was a firm believer in the Great Inland Sea; it existed all right, but he was a good 20 million years too late for it. At Depot Glen in far north-western New South Wales they became trapped for 6 months on the only waterhole anywhere around - and were remarkably lucky to find it! The effects of heat and drought were horrific. He reported "every screw in our boxes has been drawn, and the horn handles of our instruments, as well as our combs, were split into fine laminae. The lead dropped out of our pencils... our hair, as well as the wool on our sheep, ceased to grow, and our nails had become brittle as glass. The flour lost 8% of its original weight .... and we found it difficult to write or draw, so rapidly did the fluid dry in our pens and brushes." Scurvy racked them, and the second-in-command, James Poole, died of it. Nonetheless, when rain did finally come, he pushed on rather than retreating, finally being defeated by the dunes of the Simpson Desert. They returned to Adelaide after 18 months, his health destroyed.
Sturt's Desert Rose Gossypium sturtianum, Alice Springs.
This superb member of the cotton genus is the Northern Territory floral emblem.
He was by now a committed Australian, but still felt obliged to return to England where he believed his children needed to be to ensure their futures. He lived out his days peacefully enough, though he was always short of money.

In addition to the plants mentioned above which were named for him (and others which were so named, but later found to have been already described), the best-known is undoubtedly Sturt's Desert Pea (also called just Sturt Pea) Swainsona formosa, the state emblem of South Australia, though it is found in all the mainland states except Victoria. However, although it has had various scientific names from collections in different parts of the country (including ones honouring William Dampier and John Oxley) it was never called formally for Sturt. Nor was he the first to record it - indeed William Dampier had done so back in 1699 on the north-western coast, and Cunningham had reported it from both there and western New South Wales. It seems however that Sturt first brought it to the public attention, when he found it near the site of the present Broken Hill during his great 1844 expedition. He reported it "in splendid blossom on the plains. It was growing amidst barrenness and decay, but its long runners were covered with flowers that gave a crimson tint to the ground." 
Sturt's Desert Pea Swainsona formosa, Broken Hill.
This is from near the site in the Barrier Ranges where Sturt found it flowering profusely,
and brought it to the public's attention.

There are much worse ways to be remembered.

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Moonlighting

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I'm taking an easy option for today's post I'm afraid; struggling a bit with the lurgy that's going around, and leaving town soon for a significant family birthday in Sydney. 

As I've mentioned (and demonstrated!) before, I make no claims to being a good photographer, but I have fun, and I'm always drawn to shots of the moon in natural situations. For no good reason I'll share a few of those today - maybe they'll inspire you to put up a collection of your much better ones! I'd like to see them. 

First, perhaps my favourite moon shot, taken recently in the northern Flinders Ranges in South Australia, just before it got too dark. (Normally I'd leave the best until last, but you might not read that far!)
Australian Magpie Cracticus tibicen, Arkaroola
You can take 'straight' moon shots, and of course it can be a quite different colour depending on its elevation and atmospheric conditions.
These shots were taken just 23 minutes apart, soon after moonrise, on the south coast of New South Wales.
 

However I like to include other features; vegetation is an obvious choice.
Through palms, Darwin.
Through Norfolk Island Pines, south coast New South Wales.
Moon over Coolabahs, Idalia National Park, south-west Queensland.
You can't go far wrong with water either.
Moon over the Pacific, Murramarang National Park, southern New South Wales.
Same ocean, moonlight without the moon!

And I'm pretty keen on rocky hills in moonlight too.
Moonrise over Sachsayhuaman, above Cusco, southern Peruvian Andes.
Moon over the Horns, Torres del Paine National Park, southern Chile.
OK, that's enough of that! As I mentioned earlier, I'm hoping this will inspire you to show off some of yours - by all means post a link to them.

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(with a more conventional posting...)

These Wallabies Rock!

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If you came here hoping for some material on the Australian Rugby team, my apologies; whether they rock remains to be seen in weeks to come... No, this is a tribute to one of my favourite marsupial groups - indeed, one of my favourite mammal groups - the elegantly beautiful rock-wallabies. 

It seems that their ancestors were small rainforest dwellers; as the land began to dry out in the last 20 million years, the general belief is one branch of the group remained in the shrinking rainforest and still survive as the pademelons, while the rockies adapted to the increasing aridity.
Red-necked Pademelon Thylogale thetis, Lamington National Park.
More recent, and surprising, chromosomal studies suggest that their most recent connections were in fact with the tropical tree-kangaroos.
Lumholtz's Tree Kangaroos Dendrolagus lumholtzi, Atherton Tableland, Queensland.
Whichever the last link was with other kangaroos, the rock-wallabies now form a very distinct and coherent group of some 16 species, all in the genus Petrogale (ie 'rock weasel'!), superbly adapted to life on rock stacks and cliffs. Presumably it was in the inland ranges that conditions remained sufficiently amenable for their continued survival. They are scattered right across the country, so are - or were before the advent of foxes and probably dingoes - quite capable of crossing large tracts of open land.

One of the key adaptations is in the feet. Other kangaroos push off with a powerful elongated fourth toe and claw.
Agile Wallaby Macropus agilis, Cape Hillsborough National Park, Queensland.
The powerful long fourth toe and claw are quite visible.
This wouldn't work at all on rock faces, so rock-wallabies have short broad feet, with reduced claws. The gripping and pushing happens underneath; the soles of their feet are thick and spongy and the surfaces are rippled and ridged like sandshoes.
Black-footed (or Black-flanked) Rock-wallaby Petrogalelateralis, Alice Springs.
The shorter toes without protruding claws are evident.
The tail too isn't tapered, stiff and smooth like other kangaroos' (see again the Agile Wallaby above), but heavy, cylindrical, flexible and furry. When they run the tail is held high and swivels like a rudder, even helping them change direction in mid-leap.

Another 'unkangaroo-like' trait is in the nature of their care of youngsters newly emerged from the pouch. In other species the 'at foot' young simply follows mum about, suckling from the pouch as required and hopping back in as the mood strikes. Again this would be impractical on a cliff face - dangerous territory for inexperienced youngsters learning , and also for a pouch-carried baby likely to be banged on rocks when mum is hurrying - so the baby is parked in a convenient cave or crevice, to which the mother returns to feed it. When it is strong and confident enough, it embarks on a life on the rock faces. 
Black-footed Rock-wallaby, Alice Springs.
This baby will be left in a safe place while mother feeds, when it gets too big for her to continue to carry safely around.
All rock-wallabies had a common ancestor only 4 million years ago. The Short-eared Rock-wallaby P. brachyotis (and a couple of recently-recognised closely related species) from the north-west, the Proserpine Rock-wallaby P. persephone (a rare and threatened species from the tropical Queensland coast) and the southern inland Yellow-footed Rock-wallaby P. xanthopus, are the oldest and most distinct species.
Yellow-footed Rock-wallaby, Brachina Gorge, Flinders Ranges, South Australia, an 'old rocker'.
This lovely animal also demonstrates how colourful some rock-wallaby species are, relative to other kangaroos.
The most recently arisen are a group of species from the Queensland coast and ranges, whose ancestors came east from the drylands only in the last million years. Indeed some of them have only been recognised in the past 20 years or so, and several are virtually only distinguishable by chromosomes (not a generally useful field characteristic!) and range. 

A life on isolated outcrops has led to serious problems for several species, in combination with disruption and competition from feral goats, and ferocious predation from feral Red Foxes, especially when they are dislodged by the goats and try to cross open country. The once-abundant Brush-tailed Rock-wallaby P. penicillata has virtually gone from its south-eastern range, though captive breeding and re-colonisation programs are proceeding; animals bred at Tidbinbilla Nature Reserve have been released in Gariwerd (Grampians) National Park in Victoria.
Brush-tailed Rock-wallaby, Wollomombi Falls, northern New South Wales.
Only in small parts of north-eastern New South Wales and south-east Queensland
is this species still moderately common.
And while I try to hold my anthropomorphism in check, I have to confess that the sheer grace and beauty of the rock-wallabies biases me heavily in their favour. While the bigger Euro Macropus robustus, which often coexists with them, seems to power up the cliffs by sheer force, the rock-wallabies glide, like water improbably flowing uphill.
Euros, Broken Hill; powerful hill-climbing kangaroos.
Yellow-footed Rock-wallaby, Idalia National Park, south-west Queensland; all grace and poise, capable of flying up slopes where not even a toe-hold is obvious to us.
The range of the Yellow-foot is typical of the fractured remnant population of rockies; it is found in the Gawler and Flinders Ranges in South Australia, with a very few in the Barrier Ranges of western New South Wales, and a population in Idalia - all many hundreds of kilometres apart.
I've seen a couple of other species, but not with a digital camera; I intend to try to see more in the years to come. And every time I do, it's a good day.

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Fifty Shades of Black

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This is not really another in the intermittent series on colours in nature; it's rather about some of the amazingly diverse (and creative) ways in which taxonomists have sought to say simply that an organism - or part of it - is black. One simple way is to use the Latin ater, implying 'dull' or 'gloomy' black.
Black Tiger Snake Notechis ater, Twin Creek Reserve, Western Australia.
(This species is often now regarded as a subspecies of Tiger Snake N. scutatus.)
Another is niger, also Latin, suggesting glossy black (one English manifestation of it is in the word 'negro').


Black Caiman Melanosuchus niger, Blanquillo Lodge, Peruvian Amazon.
(The genus name means 'Black Crocodile', in case you missed the point; we'll get to melano- soon.)
No-one said names have to make sense of course; Black Caimans aren't particularly glossy, and White-cheeked Honeyeaters are even less so; in fact much of them isn't black at all!
White-cheeked Honeyeater Philydonyris niger, Lesueur National Park, Western Australia.
Variants of both these words can be used to describe 'degrees of blackness', or to specify black bits of the organism. 
Undertaker Orchid Pyrorchis nigricans; here the implication is 'blackish'.
Both this and the common name seem weird until you know that the pressed specimens went black in transit!
(It only flowers after a fire.)
Black Falcon Falco subniger, Bladensburg National Park, Queensland.
In other words, 'a bit less than black'!

Pied Butcherbird Cracticus nigrogularis, Lake Logue Nature Reserve, Western Australia.
The 'black throat' of the name is obvious here.

Black-headed Skimmer Crocothemis nigrifrons, National Botanic Gardens Canberra.
The species name just means 'black-fronted'.
 A derivative of ater is atratus, meaning 'clothed in black', or 'in mourning'.
Black Swans Cygnus atratus, Canberra.
Another option would be the Greek melas, but for some reason that is rarely used alone; the Long-finned Pilot Whale Globicephala melas is one of the very few examples I know of (and I'm afraid I can't illustrate it!). However melano- is often used in combination to describe a black aspect of the plant or animal. Blackwood Wattle is Acacia melanoxylon, though the wood isn't what we see when look at the plant! It is however a popular cabinet timber.There are many examples among birds in particular.
Noisy Miner Manorina melanocephala, Canberra; an abundant and pugnacious honeyeater.
Its black head distinguishes it from other miner species.
Black-breasted Buzzard Hamirostra melanosternon, Uluru National Park, Northern Territory.
Both common and species names refer to the same obvious feature.
Other black-implying names are more allegorical or even poetic. Fuliginosus for instance means literally sooty.
Black Currawong Strepera fuliginosa, Cradle Mountain, Tasmania
Black Kangaroo Paw Macropidia fuliginosa, Lesueur National Park, Western Australia.
This fabulous plant really does look sooty too!

Western Grey Kangaroo Macropus fuliginosus, Broken Hill, New South Wales.
A bit more imagination required here, though it's darker than the other grey kangaroo species.
Carbo, Latin for charcoal, is in similar vein.
Great Cormorant Phalacrocorax carbo, Narooma New South Wales.
Linnaeus named this bird Pelecanus carbo; it would certainly be a very black pelican!
Dusky Moorhen Gallinula tenebrosa, Adelaide.
According to John Gould who named it, this is a bird of shadows or dark places!

And black has long been associated with funerals, especially in western traditions, so perhaps it's not surprising that 'funereal' has been used as a descriptor of some black animals.
Yellow-tailed Black-Cockatoo Calyptorhychus funereus, Murramurang National Park, New South Wales.
Well, it's been fun, but maybe a slightly brighter topic next time!

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