Ian Fraser, talking naturally

Recently I paid a tribute to the Australian National Botanic Gardens, to me the most significant and most beautiful of the national institutions. (These things are purely subjective, and I also regularly visit and delight in some of the others, notably the National Library, Gallery, Portrait Gallery and Science Centre. However the gardens live and breathe and evolve.)

The gardens are also full of wildlife, and it is that important and exciting aspect of them that I want to talk about today. Birds are the most obvious inhabitants throughout, but they may well not be the first animals you meet there, especially on a warm day. A notable feature of the gardens is a healthy population of the colourful big Gippsland Water Dragon Itellagama (Physignathus) lesueurii, and you're quite likely to have to step around one in the carpark when you arrive. The species name honours Charles Lesueur, naturalist and artist with the Baudin expedition; more on him, and on the dragons, in the future. I'm sure they were pushed up into the developing gardens when major habitat was flooded with the filling of Lake Burley Griffin in 1963-4.

Breeding male Gippsland Water Dragon. (Gippsland is far to the south of here in Victoria, but this name refers to
subspecies howittii; Eastern Water Dragon is the name for the more northern race lesueurii.)
Their diet is broad, encompassing everything from insects to frogs to lizards to ducklings to fruit. In the Gardens
they regularly sit alongside diners at the outside cafe, being vaguely menacing - a male can be nearly a metre long.
(To save spelling it out each time, all photos in this posting were taken in the National Botanic Gardens.)

Birds also scavenge at the cafe, or just hang about hopefully.

White-winged Choughs Corcorax melanorhamphos, preening.
These obligate cooperative breeders are among the most sociable birds in the world.

Research, much of it emanating from the Australian National University just across the road, is an important activity here; young researchers with binoculars and notebooks are a common sight (though much of their work is done a lot earlier in the day than visitors see), and colour-banded birds and dragons are evident.

White-browed Scrubwren male Sericornis frontalis.
Virtually every scrubwren and Superb Fairy-wren in the Gardens wears identifying bling.

Flowers are of course an important bird-attractant, and there is something blooming every day of the year.

Eastern Spinebill females Acanthorhynchus tenuirostris, on Pityrodia sp. (from Western Australia)

New Holland Honeyeater Phylidonyris novaehollandiae, on Grevillea rosmarinifolia. Note pollen on head.
Abundant in coastal heaths, this species is very focused on the Gardens here; in 27 years living just a few hundred
metres away, with lots of suitable food plants, I never saw one in my garden.

Many other bird species are present, seasonally or permanently, using a wide range of resources.

White-faced Heron Egretta novaehollandiae, on one of the many ponds.

Gang-gang Cockatoo male Callocephalon fimbriatum at breeding hollow.

Leaden Flycatcher male Myiagra rubecula; a summer breeding migrant

The most dramatic visitor in recent times though attracted hundreds of people over a few days; it was necessary to put up fencing to protect garden beds and minimise disturbance of the mighty owl, though it didn't show many signs of angst. The same could not be said of the Gardens' population of Sugar Gliders, which was substantially depleted during its stay.

Powerful Owl Ninox strenua. Normally a very scarce resident of the ranges, this was probably a young bird dispersing.

Insects are of course abundant and diverse.

Soldier Beetles Chauliognathus lugubris. These can emerge in huge numbers on occasion.

Black-headed Skimmer Crocothemis nigrifrons.

Native fly pollinating Xerochrysum sp.

Australian Painted Lady male (?!) Vanessa kershawi, on Isotoma sp.

Native Bee on Xerochrysum sp.

Even (non-human) mammals are not uncommon in quieter corners.

Black-tailed Wallaby Wallabia bicolor having a quiet browse.

Short-beaked Echidna Tachyglossus aculeatus.

Whether your interests are in plants, animals, peacefulness or learning more about this special country, make sure you leave a few hours for the Gardens when you next visit our National Capital. Your visit certainly isn't complete until you've done so.

We're off to Kosciuszko National Park on Friday for a weekend on the (not very high!) roof of Australia.

BACK ON MONDAY.

As foreshadowed last time, we have just spent an exhilarating weekend in Kosciuszko National Park, best known for its protection of the highest parts of Australia, the alpine areas around Mount Kosciuszko, but which also encompasses nearly 700,000 hectares of subalpine and montane forests.

Looking east from Mount Kosciuszko.

It is New South Wales' largest national park, but even more importantly it is contiguous with Namadgi National Park in the Australian Capital Territory to the north, and the Victorian Alpine Parks system to the south, to create a co-operatively managed system of mountain reserves covering more than 1.6 million hectares, one of the world's great parks systems. (In Australia the states and territories are responsible for land management; in the case of the Australian Alps Agreement, the Commonwealth - the Federal government - provides a coordinating role.)

The Australian Alpine Parks system, courtesy of the Great Eastern Ranges website.
You'll probably need to click on the map to see it properly; Mt Kosciuszko can be seen half way between the two
KOSCIUSZKO NATIONAL PARK labels. The reason that the Victoria/NSW border suddenly becomes wobbly
in the middle of the parks is that from there on to the west it is defined by the Murray River, which rises in the Alps.

Mount Kosciuszko is only 2,230 metres above sea level, a rather puny 'highest point' by world standards, but it is all to do with the nature of Australia itself. The Australian Alps are an old range, and in the stable centre of a continental plate. Loftier ranges, like the Himalayas, the Andes and the New Guinea ranges, are young and growing; at the edge of their plates they are constantly thrust upwards by the irresistible mass of the plate itself behind them, crashing into the adjacent plate. Mount Kosciuszko is long past its glorious growing days, and is slowing but inexorably eroding away.

Mount Kosciuszko from 4.5 kilometres away, with the access track in the foreground. This track is sealed, and mostly raised above the boggy ground to prevent erosion, for its entire length. From the top of the chair lift at 1930 metres above sea level, above the resort village of Thredbo, the 6.5 kilometre track rises gently for another 300 metres.

One might reasonably suspect that Kosciuszko is not an 'Australian' name - or at least neither indigenous or Anglo-Celtic. One would be correct. 'Count' Paul Strzelecki (there is some evidence that the honorific was self-bestowed) arrived from Poland in 1839 as a competent field geologist who had worked in the Scottish highlands. The following year he undertook an expedition south from Sydney to seek grazing land in what is now Victoria. En route he detoured to climb the highest part of the alps, via the precipitous ascent from the Murray Valley to the west. He climbed and named 'Kosciuszko' the mountain that he deemed to be the highest, after a Polish patriot and fighter for freedom, on the basis that the rounded summit supposedly resembled Kosciuszko's tomb in Krakow! Unfortunately it seems certain that he actually climbed nearby Mt Townsend, as it now is, which is lower by some 45 metres. For a short time in the 1890s the 'real' Kosciuszko was named Townsend (after the surveyor who first mapped the range), but in 1892 the names were officially switched to honour Strzelecki's intention.

Granite boulders on the slopes of Mount Kosciuszko.

Before leaving Poland Strzelecki had tried to elope with Adyn Turno, but her parents intervened and they both remained single for life, corresponding for many years. He sent her a pressed flower from the mountain, "the highest peak on the continent - the first in the New World bearing a Polish name. I believe that you will be the first Polish woman to have a flower from that mountain. Let it remind you for ever of freedom, patriotism and love." Poignant stuff, though his prediction in the second sentence seems unnecessarily cautious!

As the football commentators like to say (apparently without irony), our walk was of two halves. It was windy pretty much throughout, but on the outward walk the clouds hung low and the views were mostly non-existent. It was very atmospheric though.

Granites predominate; in fact they underlie most of the park. They are the same 400 million year old rocks
that form the Lachlan Fold Belt, a 700 kilometre wide band under much of south-eastern Australia.

Small streams, fed by snow melt, are everywhere.

Little Ravens Corvus mellori on Mount Kosciuszko itself.
They forage for Bogong Moths Agrotis infusa which over-summer in the granite crevices.

I don't normally intrude pictures of myself here, but this portrait of us on the summit summarises the conditions.

No, you can't see wind, but my beard doesn't normally grow sideways!

However, as we sheltered just below the summit to eat something, the mist started to clear below us.

This is the valley that holds the source of the Snowy River, of some significance in Anglo-Australian folk traditions.
The ballad 'The Man from Snowy River' by journalist and poet Banjo Paterson is one of the best-known Australian poems; it was the title poem of a collection of his verse which sold 7000 copies in a few weeks in 1890.

From there on the views were stunning for our return walk.

This means lots more wonderful granites in large part!

This is also one of the very few glacial landscapes in mainland Australia, though glaciers probably only covered a few square kilometres up here in the most recent glaciation, ending some 13,000 years ago. For perhaps the previous 10,000 years here though, the ice was up to 100 metres thick. Some of the clearest - and most aesthetic - evidence is in the form of the series of glacial lakes. Most formed when the terminal moraine, the rocks and soil bulldozed down the slopes by the front of the glacier, created a dam across the gouged-out valley.


Lake Cootapatamba. The dam wall, comprising the terminal moraine, can be clearly seen to the left of the lake. The U-shaped valley is another typical glacial form, carved by the ice as it progressed.

There is more I want to say of course, including about plants and (a few) animals, but this posting is probably already as much as you want to read for today, so I'll continue this in a couple more offerings during the week.

However, I must mention one surreal encounter, on the windy misty slopes of Kosciuszko, with a procession of Polish-Australians led by a man carrying a large wooden cross! Lou, my partner, is a journalist to her marrow, and whipped out her tape recorder (it's true!) and put together the story that you can read here if you like.

BACK ON WEDNESDAY

In my last posting I talked a bit about this significant alpine and montane park, but I couldn't do it justice in one entry, so here's a bit more, specifically on trees - where and why they aren't, and a few that are! The alpine zone, ecologically, is that area above the tree line, where the vegetation comprises only shrubs and herbs.

Granite-strewn alpine zone, Kosciuszko National Park.

It is a phenomenon of mountain landscapes everywhere.

El Cajas National Park, Ecuador; here in the tropics the tree-line is close to 4000masl.
The habitat is known here as paramo.

Andes north of Cusco, Peru. Again the altitude is 4000masl, but here we can see the trees pushing higher up the mountains in the shelter of gullies. Locally this is called puna.

Torres del Paine National Park, Chilean Patagonia.
At 51 degrees south, the foreground is less than 300 metres above sea level.

It can look a bit bleak at first glance, but the beauty is both in the huge spaciousness of it, and in the detail of life at smaller scale. The alpine zone is defined throughout the world, as we approach the poles and increase in altitude, by the point at which the mean temperature of the warmest month is less than 10 degrees C. Here there is simply not enough available solar energy to build and maintain the massive trunks and supporting root systems that define a tree. In Kosciuszko this occurs at about the 1800 metres above sea level (masl) mark, but it changes with local conditions; in sheltered situations it can be as high as 2000masl. As we'd expect it gets higher at lower latitudes, and falls towards sea-level closer to the poles, as illustrated above.

In Australia the true alpine zone comprises around 0.01% of the land surface, and most of that is in Tasmania. It is a relic of the glacial times, most recently between approximately 25,000 and 10,000 years ago, when cold windy treeless steppes covered much of south-eastern Australia. Now the habitat and its plants and animals survive only on a few high isolated mountain islands.

The actual tree-line can be quite dramatic.

Tree line at around 1850masl, Kosciuszko NP.

Tree line at 1000masl, near Puerto Natales, southern Chile.

Lower down of course there are trees, with the wonderful Snow Gums Eucalyptus pauciflora being the only ones capable of surviving up to the tree line. Here are a few trees that demanded to be admired and recorded on our weekend visit.

Old Snow Gums, above and below, Charlottes Pass. Here at 1850masl trees are at their limits of growth and
they survive because the massive granite boulders provide a heat sink. Nonetheless they probably
only grow for a few weeks a year, and these are hundreds of years old.

Black Sallee E. stellulata in the rain.
The name comes from an old English word for willow, and was applied because they often grow in
boggy and frosty situations. Normally the trunk is a beautiful smooth olive-copper colour, but the bark
turns red just before dropping off.

Candlebark Gum E. rubra.
The common name is based on the observation that in a fire, burning bark from this gum can be
hurled hundreds of metres ahead of the fire front. For most of the year the trunk is white, but the old bark before being
shed turns dramatically red, orange or pink.

I still want to show some of the relatively few flowers and fewer animals that we saw - next time.

BACK FRIDAY

This is the third - and last - of my postings based on our delightful weekend (last weekend) in Kosci, as it's affectionately known here. The high country in summer is rich in flowers and insects (birds are a bit limited, as there are easier pickings lower down), but we were a bit late to get the full benefit of that. Accordingly a couple of the pics below are from a working trip I did there a couple of years back.

This will basically be just a gallery.

Hoary Sunrays Leucochrysum albicans above Lake Cootapatamba.
This daisy grows widely, including down around Canberra.
However more than twenty species of plants are found only in the park.

Brachycome obovata growing entirely in water. Cold feet!


Ribbony Grass Chionochloa frigida.This is primarily a New Zealand genus, with only a couple of species in Australia.

Alpine Gentians Gentianella muelleriana, above and below. One of the last of the summer flowers.

The lines are guides for pollinating insects.

Purple Eyebright Euphrasia collina. Eyebrights were supposed to cure eye afflictions - Milton mentioned that, though he still went blind, poor man. They grow in association with root fungi, and can't be cultivated; another reason to go to the mountains in summer!

Alpine Mint-bush Prostanthera cuneata. A lovely shrub, but only a couple of flowers were left.

Snow Beard-heath Leucopogon montanus. Lower down it grows as a shrub, but up here it,
like many other species, lies as a mat on the ground to avoid the wind.

Grasshopper on Xerochrysum apiculatum. (Taken on an earlier trip.)

Bidgee-widgee Acaena novae-zelandiae. The purpose of the burry fruits
is obvious in the picture below. My boots are just substituting for a wombat's fur!

Metallic Green Damselfly Austrolestes cingulatus. (Also taken on the earlier trip; too cold for insects last week!)

Little Ravens Corvus mellori prowl the meadows (and the village!) searching mostly for insects.

Well that's it for today, and for this topic - for now anyway, we intend to be back there a bit earlier in the season next summer.

Speaking of summer, yesterday it officially ended here yesterday (we use the meteorological definition here) - and a cold wet miserable last day of summer it was too. Personally I regret its passing but every season has something for a naturalist.

BACK ON MONDAY

I suspect that if I were rather smaller - the size of a silverfish say - I would find this a pretty terrifying prospect. I probably wouldn't be given much time to consider the matter however.

Female Huntsman Spider Isopeda villosa, on our bedroom wall.
I am grateful to Dr Linda S Rayor of Cornell University for identifying her for me, instantly and graciously,
and to Dr Dave Rowell of the Australian National University for forwarding my request to her.

The greatest initial threat to me, in my temporary guise as a silverfish, would be those eight long quick legs. Most spiders have two pairs facing forwards and two back, and walk fairly deliberately with the bodies held high.

Orbweb Spider (possibly Eriophora transmarina, a very variable species) showing the leg configuration
of most spiders.

The huntsmen (in this case Family Sparassidae) have all four pairs bending backwards; perhaps counter-intuitively they run sideways however! Their body touches the ground as they run.

Another view of 'our' huntress. The splayed out legs can be seen clearly, along with the fact that each has seven joints.
The two joints closest to the body are short, but in huntsmen the outermost one, the tarsus (the 'foot') is unusually long. Overall this gives great agility.

The photos here were taken on a vertical wall, which she glides over as easily as if it were horizontal. Most spiders have three little claws on the tip of each tarsus - the outermost leg segment. In this magnified shot of the two rearmost tarsi, we can see that she has two such claws; what we can't really make out is that instead of the third claw she has a brush running the length of the underside of the tarsus to further help her grip the surface.

We can just see the two claws on each tarsus.

We can also clearly see the hairs which cover her legs (her name villosa means hairy). These are sensitive to vibrations, including those of air currents.

A closer view of the head wouldn't give me much confidence either, in my silverfish persona.

Eight eyes (four small ones above four large ones) would ensure I was clearly visible to her, were I a silverfish. The massive chelicerae (fangs), between two palps, are definitely all the better to eat me with. More below.

Unlike insects, with three body segments, spiders have just two; they have an abdomen like an insect, but a single cephalothorax includes head and 'chest', and carries the legs. The first pair of appendages on the cephalothorax are the massive chelicerae, seen here immediately below the four larger eyes. They comprise the large basal segments, which can be effective crushers, folded into which (out of sight) are hard sharp fangs, which inject venom via a tube. Her mouth parts are hidden behind them. Rapidly resuming my human persona, even if I were to harass her enough to make her bite me, the venom would do me no harm - it is mostly designed to break down insect bodies for easy digestion. The fangs would give me a painful - and fully deserved - stab though.

Outside the chelicerae is a pair of six-jointed palps, resembling short legs (see pic above). They are sensory and are used to help manipulate food; in the male however they are swollen at the tip and are effectively sexual organs, carrying and transferring sperm.

These spiders are often referred to as tarantulas. The name it seems originated with the town of Taranto in Italy, which also gave its name to the dance Tarantella. The spider, which was actually a wolf spider of the family Lycosidae, was reputed to cause the dance by biting - or alternatively the dance was the antidote to the bite, it all depends on your choice of myth. It seems that the bite of the local wolf spider could in fact cause considerable distress, though there are diverging views on this. However this is the opinion of Bert Brunet in his excellent Silken Web; a natural history of Australian spiders, and I readily defer to him. Other opinions always welcomed however!

Whatever the truth of that, the name became transferred to the primitive big hairy scary-looking (but generally harmless) ground-dwelling American spiders of the family Theraphosidae, though the family is found through much of the warmer world. How and why the name then transferred here, to yet another family of spiders, is unclear.

Tarantulas; above Blanquillo Lodge Peru, below Sacha Lodge Ecuador

Whatever you choose to call her, our huntress is a very welcome member of our household. Tough luck silverfish!

Next time it's probably time to return to the long-promised discussion of red and black creatures.

BACK ON THURSDAY

It's been a while now since my last posting on colours in nature - red on that occasion - wherein I promised to get back to look at some of the many organisms, especially birds, which combine red and black to very striking effect. At least it's striking to our eyes, but we must assume that it is to other creatures as well, given its relative prevalence. Red is a colour intended to be seen; to attract a mate, to warn of the hazards of trying to eat the wearer, or in a plant to attract an animal to pollinate or distribute seeds in ripe fruit.

Masked Crimson Tanager Ramphocelus nigrogularis, Amazonia Lodge, Peru.
In this species both sexes carry the bright colours, though the female is slightly duller.

I think in the case of animals the combination with black is a variation on the theme, though in shadowy situations such as rainforest it presumably breaks up the outline and perhaps confuses predators for the essential extra second or so.

Black-necked Red Cotinga Phoenicircus nigricollis, Yasuni NP, Ecuador.
This is regarded as a tough bird to find, and I feel very privileged to have actually got a usable photo of one.
In this case the female has brown instead of black.

We know very little about this bird, though males seem to display. While there is some doubt about whether it's more closely related to cotingas or manikins, this does fit in with a pair of much better-known cotinga species, the cocks-of-the-rock. Here the males form a display lek, with the most successful birds taking the prized central positions, to where the waiting females head. Like the Black-necked Red Cotinga, she too is brown rather than red.

Andean Cock-of-the-Rock Rupicola peruvianus:
males, Manu, Peru above; female, Aguas Calientes, Peru, below.

It is significant that in many smaller red and black birds only the male is coloured; his job is to intimidate other males, impress females with his condition and his ability to survive despite being so conspicuous, and perhaps to distract predators from her, the nest and eggs. She has no need at all to be easily seen.

Scarlet Robin Petroica boodang, Canberra; male above, female below.
The shot above doesn't show how black he is on top.

Other examples of startlingly red and black males with brown-grey females follow.

Long-tailed Meadowlark Sturnella loyca, Chilean Patagonia.
Male above, female below.

Northern Red Bishop Euplectes franciscanus, Murchison Falls NP, Uganda.
Not only are bishop and weaver females brown, but they are virtually indistinguishable from each other.

Red-backed Fairy-wren Malurus melanocephalus, Ingham, Queensland.
Like all fairy-wrens females, she is plain brown, whereas he glows through the scrub.

On the other hand the females of some larger, more pugnacious species can afford to be as conspicuous as their blokes.

Papyrus Gonolek Laniarius mufumbiri, near Kagadi, Uganda.
A bush-shrike, this is a notorious skulker, which is another reason for both members of the pair to be visisble.

Magellanic Woodpecker Campephilus magellanicus,Torres del Paine NP, southern Chile.
This is the male; she has less red in the head, but still stands out. This is a big, dramatic woodpecker!

Examples of red and black in other organisms (and I'm limiting myself here to bright reds, not rusty or orange) are less easy to find.

Millipede, Mt Kupe, western Cameroon.
Many millipedes taste bad, and I suspect that this one is emphasising the point.

Nor can I find many plant examples, but I'm happy to go out today with one of my favourite Australian wildflowers, and the floral emblem of my birth-state, South Australia.

Sturt's Desert Peas Swainsona formosa, Broken Hill, New South Wales.
Sprawling across the ground, these are bird-pollinated and perhaps have to be particularly striking to catch the attention of passing honeyeaters. On the other hand a bird would have to be particularly dense to miss this display!

BACK ON SUNDAY

A rule of mine when travelling is never to drive past a sewage pond without visiting to see what birds are there. (You'd be astonished how many visitor information centres have no idea where their nearest ponds are!) It's becoming tricky actually, as lawyers increasingly impose themselves and more councils are closing their ponds to public access; really, there's not much other reason to visit some of those places!

Another 'must stop for' is a bird hide. Actually, the two are not necessarily exclusive of each other. In Paarl, north-east of Cape Town, the sewage works are delightfully called the Paarl Bird Sanctuary and come with welcome signs, an information shelter, hides and picnic tables! I was most impressed. Most hides are in wetlands, though not all. In Gluepot Reserve in the South Australian mallee, and at the excellent Arid Lands Botanic Garden in Port Augusta (also South Australia), there are good and productive hides facing small artificial drinking points in dry woodland.

Nor do hides necessarily have to feature birds, though most do.

White Rhinos, above, Nyala male below,
Kumasinga Waterhole, Mkuzi Reserve, Zululand, South Africa.

This superb hide, accessed by a wooden corridor two metres high and at least 200 metres long, overlooks a small pipe-fed pool. Needless to say, birds feature heavily too - a gorgeous Purple-crowned Turaco springs to mind.

Elsewhere in South Africa I recall the impressive Sable Hide in Kruger National Park, where one can rent a fold-down bed for the night. This is an especial treat because in most of Kruger you are forbidden to get out of the vehicle, on pain of instant expulsion from the park. (Or death, depending on whether the rangers get to you before an elephant, lion or buffalo.)

So, what is a hide? Essentially it is just a little room, usually wooden, with slot windows in front and perhaps the sides, and benches to sit on. Ideally the approach will be screened so that birds are not scared off even before you get to the hide.

Cygnus Hide, Kellys Swamp, Jerrabomberra Wetlands, Canberra. The brush fences screen the approaches to the hide from the birds on the water (to the left of the picture).

Crucially, it has a back wall (or usually a wooden baffle, inside or outside, masking the doorway) so that watchers sitting at the windows are not silhouetted from the front of the hide. Birds are nervous about this, and generally won't come as close. It's a universally recognised requirement, so it's a surprise to find a few hides that overlook this necessity. In Australia, Abattoir Swamp Environmental Park near Julatten in tropical Queensland is one which is notorious for this design flaw (at least it was last time I was there, some years ago now; if it's been rectified I'd be glad to pass on the good news). This hide is also notorious for being bird-poor in a very bird-rich area, though of course I can't say that this is the only reason. New hides near Lake Cargelligo in central western New South Wales were built similarly flawed, though I've heard that there is interest in fixing them.

Embarrassingly and incomprehensibly, the formerly excellent hides at Kellys Swamp, Jerrabomberra Wetlands - Canberra's premier wetlands - have recently been severely compromised by having the internal baffles removed so that the incumbent birders are now clearly silhouetted!

Cygnus Hide, Kellys Swamp, from a bird's eye view. Anyone sitting in the middle of the hide is now clearly outlined against the sky behind. Nor is the problem just from straight in front, as the shot below from off to one side illustrates.

Additionally, there were extra benches along the internal baffles, so there is now also less seating area. The rationale is a complete mystery. At one stage it was vaguely suggested that some people might be nervous about coming into a dark hide, but I've never met or heard of a birder unwilling to use these hides (though I know of hundreds who do). A direct written question to the board administering the wetland failed to elicit a response, so one must assume that no such survey was ever actually done and that hideophobia is an urban wetland myth.

The little screen to the right of shot in the first picture of the hide above is supposed to overcome this problem but, as the subsequent photos show, it is nowhere near high enough.

My consolation comes from my experience of cycles and corporate memory; one day someone will say "isn't it funny that they never thought to put baffles in those hides?", and they will reappear!

In Peru and Ecuador (and probably elsewhere in South America) there are hides erected at clay licks where parrots come in to collect clay at cliff faces or river banks - apparently primarily as a sodium source, though we can talk more about that another day. Some, such as this one near Amazonia Lodge on the Rio Madre de Dios, are very basic open structures, but backed by a vegetated bank.

Needless to say, the views here as elsewhere are not guaranteed!

My very favourite bird hide anywhere however is this superb two storey structure which boasts its own toilet! It is run by the Blanquillo Lodge further downstream from Amazonia Lodge.

This is only a section of it. As the parrots move to new sections of the clay bank (visible through the wooden supports below the hide itself) the hide is extended; it is at least a hundred metres long. Note the solid back wall.

Here are some views from it.

Orange-cheeked Parrots Pyrilia barrabandi and Blue-headed Parrots Pionus menstruus.

Red and Green Macaws Ara chloropterus, above and below.

Yellow-crowned Parrots Amazona ochrocephala, Mealy A. farinosa and Blue-headed Parrots.

Zone-tailed Hawk Buteo albonotatus.This is not the only predator to chance its arm (or wing) at the licks. An entry in the log book for the previous week described how an Ocelot sprang from the foliage and seized a macaw!

Finally, I must share with you this somewhat sobering sight from Peru. The previous year we had delighted in Andean Cocks-of-the-Rock Rupicola peruvianus displaying from a little rainforest hide by the road. In the intervening February very heavy rains had caused many landslides, including the one that reduced the hide to this.

Ruins of Cock-of-the-Rock Hide, San Pedro, Peru, 2010, above and below.
Fortunately it wasn't being used at the time!
When I was last there, the scene below had been dense rainforest.

However, you shouldn't really be put off using hides by this - most of them never get struck by landslides, thunderbolts or mortar shells!

And there are few if any better places on earth for just contemplating life, in between enjoying the wildlife at close range.

This is the third in a sporadic series on bird bills that are even more remarkable than this wonderful organ normally is. The previous offering in this series can be found here.

Today you get two for the price of one. Although our two stars are entirely unrelated (indeed neither has any apparent close relatives) they have surprisingly similar bills.

The dramatic Shoebill Balaeniceps rex (ie 'king whale-head!') is a big bird indeed, standing up to 1.5 metres high and with a massive and unlikely-looking bill well over 20 centimetres long. It is a resident of the huge papyrus swamps of central east Africa, from Zambia north to Sudan. Due to the difficulty in penetrating these dense wet vastnesses it is not well known, and even its populations are uncertain. Like many other large birds it soars, and this is how it is often first seen, high over the reedbeds.

Shoebill, Murchison Falls National Park.
The slightly mad-looking eyes can be a bit disconcerting, but more so I suspect
if you were about to be seized by that huge bill!
The wickedly-hooked tip can be seen below.

I feel very privileged to have seen this special bird, but we couldn't get very close.
A scattered herd of elephants was starting to take interest in us and our local guide and driver, Livingstone, was forced to thread our way out in the four-wheel drive through some very tricky broken ground, while avoiding grumpy jumbos.

The bill is an all-purpose prey trap, though its emphasis in on large fish, especially lungfish and catfish. A range of other prey has been reported, and in some areas water snakes form a significant part of the diet. In addition to the hooked tip there are serrations along the edges, for further gripping and cutting efficiency. Adults will also carry loads of water in it for chicks in the ground-based nest for the first weeks of their life, until they can walk to water.

Half the world away, in another part of Gondwana, the Boat-billed Heron Cochlearius cochlearius is found throughout much of the tropical Americas, from Mexico south through central America and down to northern Argentina. Despite this large range it is not often seen - I've only seen it twice in nine trips to South America. It is currently placed in its own sub-family, but there are those who would reinstate an older view which believes that it warrants its own family, like the Shoebill.

Boat-billed Heron, Sacha Lodge, Amazonian Ecuador.
One of the reasons it is hard to find is that it is nocturnal, coming out from a secluded roost on dusk.
This beautiful bird was seen from a canoe in a channel in fading light, sorely testing both my basic camera and me!
(In the circumstances I wasn't too unhappy with this result.)
The snappy long black crest can just be seen.

It is only a third the size of the Shoebill, and so the similarly flattened and hooked bill is much smaller. It too snaps up a range of prey, especially fish and invertebrates and small land mammals. It also uses it as a scoop, in a way that no other heron does that I can think of.

More marvellous bills coming up sometime in the future; I hope you've enjoyed these as much as I did.

MEANTIME, BACK FRIDAY

Last November I waxed lyrical about one of my favourite national parks, Monga, which is just off the highway on the way from Canberra to the coast at Batemans Bay - a well-trodden route indeed in this part of the world. (One we are treading ourselves this weekend.) During this week I returned there, following a heads-up from my friend Martin of House of Fran-Mart - the primary motive was the fact that the Pinkwoods are flowering.

Pinkwood (or Plumwood) Eucryphia moorei, Monga National Park

Eucryphia is a small ancient rainforest genus of trees which can trace their antecedents directly back to Gondwana. Five species are from eastern Australia, while two grow in Patagonian rainforests. It is remarkable to find one genus growing in two continents which have been separated for at least 60 million years; not only must it have already evolved and existed in both places by then, but it has changed very little in the meantime.

Ulmo Eucryphia cordifolia, southern Chile.
Photo courtesy Franz Xaver; my own photo of it is too terrible to use!

Until recently it was the sole occupant of family Eucryphiaceae, but more recent thinking places it in the related and much larger rainforest family Cunoniaceae (known in Australia for NSW Christmas Bush Ceratopetalum gummiferum and Coachwood C. apetalum). One species E. jinksii was discovered in subtropical northern New South Wales less than 20 years ago; another E. wilkiei lives only in one population on one mountain in tropical Queensland.

Eucryphia wilkiei National Botanic Gardens, Canberra.

The best-known species in Australia is probably Leatherwood E. lucida from Tasmania, which produces strong-tasting honey - I think it is probably the pinnacle of honeys, but others find it too robust. It is no coincidence that Ulmoproduces a similar honey in Chile and Argentina.

Pinkwood, the species I went to Monga to admire, is limited to New South Wales (other than an incursion of a kilometre or so into far eastern Victoria). It grows in a series of isolated populations in a unique type of cool temperate rainforest on near-coastal ranges in southern New South Wales.

I was lucky - the ground was liberally carpeted with untold millions of fallen petals. A few days more and I might have struggled to find any intact flowers.

Pinkwood petals scattered on a treefern (above) and the boardwalk (below),
as well as everywhere in between!

Up towards the ridge a little I was pleased to see the first of the Sunshine Wattle Acacia terminalis for the season; this lovely bright wattle flowers right through winter and can brighten a dull cold day. No requirement for that service on this day however!

Sunshine Wattle, Monga National Park.

The delightful Eastern Yellow Robins Eopsaltria australis are a feature of the park; if anything the young birds which are now making their way in the world are even more curious and confiding than their parents.

Immature Eastern Yellow Robin, which would have hatched in spring.
Below, it landed almost on my feet in pouncing on an insect snack.

Finally on birds I offer this pretty ordinary snap, as the only one I've ever managed of this ever-moving rainforest specialist, which is close to the southern limit of its range here.

Large-billed Scrubwren Sericornis magnirostris.
From side on the heavy bill points slightly upwards, as if glued on crookedly.

As suggested in the title, I also stopped between home and Monga to investigate a couple of orchid reports I'd been given; both sites are between Braidwood and Monga, but it's not wise, sadly, to be too precise with unusual orchid localities in a public forum.

Scarlet Greenhood Diplodium (Pterostylis) coccinum.
Greenhood orchids are of course supposed to be green; this stunner is a dramatic exception.

Mongarlowe Midge Orchid Corunastylis oligantha.
The midge orchids can be a bit tricky to locate, down among the grass;
these are less than 15cm high, with flowers only a few millimetres long.
They are one of the groups of 'upside down' orchids, in case you're having trouble interpreting the picture.

As I've said before, I'll talk about the upside down orchids in more detail at some stage. I'll also do a posting on some more autumn orchids.

Meantime, a last image of a very old and very beautiful flower whose ancestors looked like this when the southern lands were still one.

Pinkwood, Monga National Park.

BACK ON TUESDAY

As I have mentioned before, Lord Howe Island is a very special place. One very memorable walk is along the tops of the Malabar Cliffs at the north end of the main island. It's a bit of a climb, but only to a bit over 200 metres above sea level, starting at Ned's Beach. From up here though - initially on Malabar Hill, then along the cliffs themselves and finally on Kim's Lookout at the western end (underneath the 'b' of Malabar in the map below) - the views are superb, south right along the island and north to the offshore islets.

Here are a few of those views.

Ned's Beach from Malabar Hill; the route up gives grand views out to the sea to the east.

Looking west along the cliffs.

view south from Malabar Hill; the settlement is to the right, Mounts Lidgbird and Gower loom in the distance.

Same view south, from Kim's Lookout, a couple of kilometres to the west.

Admiralty Islands from the Malabar Cliffs, looking north.

There is no doubt though that one of the highlights of the walk in summer is the floating parade of Red-tailed Tropicbirds Phaethon rubricauda that drift past, often displaying, sometimes in elegant courtship pairs. In these flights one bird drifts along while the other 'stands up' in the air, pushing so that it goes backwards, while both point their tails towards each other. At this time of year they nest on the cliff faces, in scrapes on the ground; here on Lord Howe is apparently the greatest breeding concentration in the world.

They range across the Pacific and Indian Oceans, but the places where we can enjoy them so readily from land are very limited.

Sadly I didn't manage to catch a photo of the pair display, though we watched them entranced for ages.

These were the stars, but it would be unfair to ignore some of the other beautiful seabirds that soared along the cliffs.

Masked Booby Sula dactylatra;this is a big bird and their vertical plunges into the ocean from high up, chasing fish, are dramatic.

Sooty Tern, Onychoprion fuscatus;
they breed everywhere on the island in noisy restless colonies - the locals call them Wideawakes.

There are many excellent reasons to spend a week on Lord Howe; the Malabar Cliffs is one good one.

Roach Island from Malabar Cliffs.

BACK ON FRIDAY

I suspect that the majority of Canberrans make the 150km journey across the edge of the Monaro Plains, through historic Braidwood and down the steep curves of forested Clyde Mountain to Batemans Bay at least once a year. Many own or have access to holiday homes of varying grandeur or simplicity up and down the coast; we don't, though we do spend three or four weekends a year there in general. 'The Bay' is a sprawling conurbation now, but there are still quiet little off-road settlements nearby. We have a flexible set of rituals while we're there, but one unbreakable rule is a visit to the delightful Eurobodalla Regional Botanic Gardens, 42 tranquil hectares of forest and open space dedicated to local native plants.

As you will have by now divined, this is to be another in my occasional series on favourite botanic gardens, the most recent of which you can find here.

Prostanthera porcata, a threatened species from rugged slopes in the nearby Budawang NP, only described in 1984.
All plants in the gardens are local, which is defined here as the catchments of the Clyde, Deua and Tuross Rivers.

The story of the ERBG (if I may be so familiar) is above all one of community spirit and an unusually successful co-operative venture between community, local government and a state government department. In 1986, in a reversal of the usual way of doing things, a Friends group was formed to press for a local native botanic gardens. In 1988 the Eurobodalla Shire came on board, and NSW State Forests was convinced to lease the selected area - which had not been logged for 100 years - to the shire for use as a botanic gardens. A management committee was established to oversee the development, and it still guides the garden's directions and ongoing development. Most of the financial support comes from the shire, with the help of government grants and vigorous fund-raising by the Friends.

As a result of being unlogged since the early 20th century, there are some big original eucalypts
in the forests of the Gardens.

The path has not been easy. A massive bushfire in January 1994 set development back a long way. In September 2010 a destructive storm brought down numerous trees, one of which crushed the new orchid house just prior to its scheduled opening. Some of the 7km of walking tracks are still closed following that event, awaiting the funds to clear them.

Nonetheless they are now a delight to visit. The first thing a visitor encounters is the cafe and visitors' centre, which come into view as we cross a little bridge over Pat's Creek, usually busy with birds.

The Chef's Cap Cafe is on the left, with the Wallace Herbarium on the right.
The tower provides cooling in summer by drawing up hot air from the buildings.

We always indulge in at least a coffee, if not lunch, at the cafe, attended invariably
by busily speculative Superb Fairy-wrens.

Superb Fairy-wren Malurus cyaneus male, moulting into his plain winter garb,
sharing a table at the Chef's Cap Cafe.

The garden beds surrounding the buildings feature relatively fire-resistant plants, to complement the fire-resistant design of the buildings themselves.

Looking south from the Visitors' Centre.

Chef's Cap Correa Correa baeuerlenii, from which the cafe takes its name.
It is limited to about 150km of forests south from here.

Three quarters of the area is retained as original forest, with walking tracks winding through.

Wet sclerophyll forest along the gully of Deep Creek.

The tracks feature information signs, including on indigenous usage of local plants.

Discussion of indigenous use of Burrawang, the cycad Macrozamia communis, alongside the plant.

The ten hectares of cleared land were already cleared when the site was chosen; they are designed to encourage use, for picnics and family gatherings. Children are well-catered for.

Excellent playground, including large robust musical instruments, such as the 'harp' below, played by hitting with the metal pipes supplied and tied on!

All-weather picnic shelter.

Covered stage at amphitheatre, used for concerts.

Orchid house, built to replace the one destroyed in the 2010 storm.

Water features strongly throughout the gardens; water for the ponds is mostly drawn from Deep Creek.

Two of the rich, near natural-seeming artificial ponds.

From the bird hide looking out over extensive wetland at the north-western end of the Gardens.

And speaking of birds, they are of course another feature; here are just a couple that I've photographed here at different times.

Jacky WinterMicroeca fascinans, an Australian robin, which hunts insects by 'perching and pouncing'.

Eastern Whipbirds Psophodes olivaceusare generally cryptic, but sometimes come out to feed on the lawns here.

Australian Wood Ducks Chenonetta jubata, appreciate both the ponds and the lawns where they graze.

Fan-tailed Cuckoos Cacomantis flabelliformis are spring and summer visitors, when their perpetual downward trills compete with the cicada chorus.

The gardens are well-marked on the left about five kilometres south of Batemans Bay on the left of the Princes Highway. Bearing in mind that they're closed on Monday and Tuesday, make sure you put some time aside to visit next time you're down that way. Have a look here for some more information. Beware before you visit though - you'll be hooked too.

BACK MONDAY

I don't generally think of March as being a good time for orchids around here, but when I started to go through my records, I decided that I might be wrong. In this part of the world at least, it's not so much a time for colourful ones, but there are quite a few fascinating and beautiful orchids (sorry, tautology!) to be found in this first month of autumn. As I've mentioned before, Australia uses the Meteorological definition of the seasons, according to which autumn officially began on 1 March.

Several species of greenhoods can be seen now. A brief word on the somewhat fraught state of Australian orchid taxonomy to explain oddities relating to genus names. Traditionally all greenhoods - some 200 or so of them - were placed in the genus Pterostylis, and for probably the majority of people they still are. However, as part of their gargantuan task of re-examining nearly all the Australian orchid genera, David Jones and Mark Clements of the Australian Herbarium split Pterostylis into 16 genera, mostly based on already recognised sub-genera. Their work was thorough and largely based on biochemical criteria. Jones, recently retired, is widely regarded as the doyen of Australian orchid taxonomists and conservationists; Clements is also well-respected. Unfortunately they chose to publish in The Orchadian, the journal of the Australasian Native Orchid Society - which does not peer-review its articles. In large part due to this, much of their conclusions have not been accepted by other taxonomists.

However, the only comprehensive identification guide to Australian orchids is written by Jones - so you see our problem... Around here it's even trickier as he also authored an excellent Field Guide to the Orchids of the Australian Capital Territory, which we all rely on. All of which is a long-winded way of explaining why several of the species which follow have two genus names; given that my audience is international, I'll use the most widely-accepted names, with Jones' names in brackets. (The same issues arise with some other genera, but they are not relevant to this posting other than the last species featured.)

All these photos were taken in March, but not necessarily this year. Except where specified, the locations are all in the Australian Capital Territory.

Summer Greenhood Pterostylis(Diplodium) decurvum, Tidbinbilla Nature Reserve.

Dainty Greenhood Pterostylis(Diplodium) reflexum, Black Mountain, Canberra.
Below, part of a large colony.

Little Dumpies Pterostylis(Diplodium) truncatum, Black Mountain, Canberra.
I do like such quaint folk names, whose origins are now lost to us.

Blushing Tiny Greenhood Pterostylis(Speculantha) rubescens, Black Mountain, Canberra.

The rest of the featured orchids are not greenhoods, though there are certainly other greenhoods to be found. Dennis Wilson of The Nature of Robertson features a rare one here.

Large Midge Orchid Acianthus exsertus, Black Mountain, Canberra; above and below.
These were probably atypically early, but were well within March.
('Large' is relative, it's worth pointing out!)

Parson's Bands Eriochilus cucullatus,
above (Smith's Road near Angle Crossing) and below (Mongarlowe, New South Wales).
These delightful little orchids flower from late summer well into autumn; they range from rich pink to white.

Mountain Spiral Orchid Spiranthes alticola, Tidbinbilla Nature Reserve.
This a truly exquisite little orchid, with each flower being no more than 5mm long;
there can be dozens of them twisting up the stem.
This used to be regarded as one species, S. sinensis, found all the way to China, but Australian plants are now known as S. australis; the species illustrated is recently described by David Jones and is widely accepted.

Tiny Strand Orchid Bulbophyllyum (Adelopetalum) exiguum, Nowra, New South Wales.
Another delightful miniature, flowers only 5mm long, growing on logs and rocks in rainforest.The splitting of Bulbophyllum by Jones is also contentious

For a couple of other March orchids, see my recent post on my visit to Monga National Park.

BACK ON THURSDAY

In my last posting I featured a few greenhood orchids, but I realised later that they probably won't be familiar to readers outside of Australia, and even to many people living here. I thought I might rectify that today. As a group they are almost restricted to Australia, and they are fairly modest and inconspicuous. They are over 200 strong however, and I find them fascinating. As I mentioned in the last posting, there is some turmoil here over the taxonomy; they have always been lumped into just one genus, Pterostylis, but recently, and controversially, the genus has been divided into 16 genera by Jones and Clements. I shall use their genus names here, because that's how they appear in Jones' mighty Complete Guide to Native Orchids of Australia, the only comprehensive work.

They seem to be an old group with no close relations; indeed they are so specialised that they are not always immediately recognised as orchids. To explain just how they're composed, allow me to give you a brief revision of the basics of an orchid flower, using a more 'standard' flower type.

Diuris punctata, Tallong, New South Wales.
(Please forgive the washed-out image - I must find a better way of labelling pics and getting them to this format.)
Unlike most flowers, orchids (and lilies) have sepals - the outer ring of flower parts - which are as large and colourful as the petals. There is one dorsal sepal at the top of the flower, and two lateral sepals lower down. There are two dorsal petals (which don't look as though they arise inside the sepals, but look at the top flower), with the third petal forming an insect landing platform called the labellum (lip). And that'll do for now!

In greenhoods, the two dorsal petals and the dorsal sepal strongly overlap to form the hood, or galea.

Summer Greenhood, Diplodium decurvum, Tidbinbilla Nature Reserve near Canberra.
The hood, or galea, covers the top of the flower; it is hard to make out the three different parts of it.

This picture also shows two other features of greenhoods. One is that the lateral sepals are fused, unlike those of other orchids like the Diuris above. The other is the essential labellum, which is tucked away inside the flower, sometimes protruding but in some cases always hidden. No greenhood provides a nectar reward to hard-working pollinating insects; all of them attract small male flies, either fungus gnats or mosquitoes, with a pseudo-pheromone, a chemical that mimics the 'come hither' scent of an interested female gnat or mosquito. When the amorously hopeful insect contacts the hinged labellum it snaps back, pinning the insect against the column, which contains both pollen and style. In its struggle the unfortunate gnat collects the sticky pollen, or delivers a bundle it's already carrying.

Two basic groups of greenhoods are recognised. The larger group is characterised by having upswept lateral sepals like the summer greenhood above, and the species featured in my last posting. Here are some more of this grouping.

Snail Orchid Linguella sp., Alligator Gorge, South Australia.
There are over 30 species of the little snail orchids, mostly in Western Australia;
unfortunately, at last count only five of them had been described!

Large Mountain Greenhood Pterostylis monticola, Namadgi National Park near Canberra.
Some 25 Australian species remain in Pterostylis under Jones' taxonomy. Here the labellum protrudes.

Nodding Greenhood Pterostylis nutans, Micalong Falls, New South Wales.
Not dozing, they always look like this!

Trim Greenhood Taurantha concinna, Callala, south coast New South Wales.
Again the labellum is obvious, protruding through the join of the two lateral sepals;
this angle is the sinus, and is used for identification.

In the other sub-group, the lateral sepals point downwards - ie they are deflexed. The leafy greenhoods are good examples of this group.

Common Leafy Greenhood Bunochilus longifolius, Callala, south coast New South Wales.
The highly mobile labellum is fully exposed and snaps shut to form a closed door when an insect enters.
It then has to struggle to get out, increasing the chances of it contacting the orchid's column.

Black-tip Greenhood Hymenochilus bicolor, Munghorn Gap NR, central western New South Wales.
These flowers are tiny. In the middle flower the fly-like labellum is exposed; in the other two it has
snapped shut, locking the insect inside.

Sikh's Whiskers (!) Oligochaetochilus boormanii Weddin Mtns NP, south-western slopes New South Wales.
Not all greenhoods are just green!

To end, a couple of more spectacular ones, albeit still in an understated way.

Jug Orchid Stamnorchis recurva, Twin Creek NR, Western Australia.
The only one of its genus, restricted to the west, and quite unmistakeable.

Unnamed Plumed Greenhood Plumatichilus sp. Alligator Gorge, South Australia.
Only four of the 14 known species of plumed greenhoods have been described;
they have in common these wonderful long yellow hairs along the labellum.

So, the greenhoods, subtle beauties. I have you've enjoyed them as much as I do.

BACK ON TUESDAY

On two occasions in western Queensland, I've come across vast numbers of what we in Australia call 'slaters' moving along roadsides in the cracking black-soil country; both occasions followed rains. (I'd not expect to see this very often - in that country you don't venture off the bitumen after a few mm of rain, and there's not much bitumen about.)

Swarming Flood Bugs Australiodillo bifrons, Diamantina River west of Winton, Queensland.

These are the so-called Flood Bugs, which live in moist soil crevices in flood plains of inland eastern Australia. Their remarkable mass movements are well-documented, but as far as I can determine their purpose is not understood; it is certainly most unusual in their group.

Slaters (apparently a Scottish term originally) are known elsewhere as pill-bugs or woodlice (among many more localised terms). They are not insects, but crustacea; like insects they belong to the phylum Arthropoda, but within a different sub-phylum that comprises mostly marine animals, including crabs and prawns. The slaters form a wholly terrestrial sub-order of some 5000 species in the Order Isopoda; there is also a similar number of aquatic Isopod species, mostly marine.

They are a very ancient group, going back at least 300 million years, when they appeared in a similar form in the fossil record. They tend to be flattened dorso-ventrally (ie top to bottom) and have seven pairs of legs, each on a body segment, which number immediately seems counter-intuitive to our prejudiced ideas of how things ought to be. What seems even odder is that immatures begin life with six segments and leg pairs, and add another one later as they moult towards adulthood. Another unique aspect of slater moulting is that they do it in two stages; while virtually all other arthropods moult all their exoskeleton at once, the slater does the back half first, and the front segments a couple of days later; the new shell is paler and pinker than the old one.

The big hind legs (or pleopods) contain gill-like breathing organs; this is one reason why they are restricted to moist areas. Up to 100 young are carried in the mother's pouch (known as a marsupium, just as a kangaroo's is).

Some species are very familiar in gardens - indeed several common Australian garden species are introduced, including the familiar Porcellio scaber from Europe. On the other hand many species live far from gardens in the dry inland (albeit in sheltered situations).

Porcellio scaber, Canberra. The big pleopods are clearly visible; other slater characteristics include
the obvious antennae (plus a very inconspicuous pair) and the eyes, which are never stalked.
The first body segment is fused to the head.

As any inspection of a compost heap will confirm, slaters play an important role in recycling dead vegetable material. A curious aspect however has emerged in western New South Wales and Victoria from as recently as 2006, where there are reports, for the first time, of slaters - including it seems our friends the Flood Bugs - eating crop seedlings, including wheat and canola. Explanations for this behavioural change tentatively include changed farming practices and climate change, but we certainly don't know for sure. We can only hope that indiscriminate poisoning doesn't follow before we properly understand what's going on.

Meantime, just a couple more images of the magnificent march of the Flood Bugs.

Above, the massed animals crossing a concrete bridge, spilling from the gutter
into the roadway. References speak of more than 100,00 individuals moving, but
I think we saw many more than that, over hundreds of metres.
Below, swarming up a road reflector sign.

BACK ON FRIDAY

As Gondwana was breaking up 100 million years ago, after half a billion years of comprising one mighty southern land, many of the most familiar elements of our living world were developing, including mammals, flowering plants and birds. Only those groups whose ancestors already existed then would be expected to occur right across the Gondwanan lands today. Family Proteaceae - Proteas, Banksia, Notros - is one such. Another comprises the most ancient of living birds, the ratites, the giant southern flightless birds.

In addition to African Ostriches (above, Western Cape) and South American rheas (Darwin's Rhea below, Seno Otway, far southern Chile), living ratites include the Australian-New Guinea cassowaries and emus and the New Zealand kiwis. Ones that didn't survive human depredations include the New Zealand moas and the Madagascan elephant birds.

Presumably the ancestral ratite (which certainly could fly) continued to get larger to outgrow its enemies, and perhaps to see better in a grassland habitat. Once the apparently magical 15kg weight limit for flying birds had been passed it had to forego the powers of flight, but there was then no limit to its size; an Emu can weight 55kg, an Ostrich 150kg and the elephant birds half a tonne! The word ratite comes from the Latin for a raft; with the loss of flight came the gradual loss of the unnecessary great flight muscles, and their attachment point - the protruding keel. The resulting flat breastbone was seen by earlier ornithologists as raft-like.

Already spread across Gondwana, they developed in different directions once they became isolated after the break-up. (However I should mention that a 2010 paper, using mitochondrial gene sequencing, claimed that the group was too young to have arisen thus, but that each group flew to its current location and subsequently each one independently lost its flight powers. I certainly can't comment on the chemistry, but this does seem such an improbable scenario that I'm waiting for some corroborative evidence before I accept it.)

All that aside, Emus are intrinsically wonderful birds, and not hard to find in inland Australia as well as in some places much nearer the coast. The name itself is not, as commonly supposed, of indigenous origin, but from the Portuguese ema, referring apparently to a crane, but more generally to any large bird (it is still used for the rhea). The sailors who reported it were Dutch, but Portuguese was then the lingua franca among European sailors in the East Indies, perhaps because the early maps were in Portuguese.

Emu Dromaius novaehollandiae, Shark Bay, Western Australia.

Emus are great nomads, walking hundreds of kilometres following rains and food sources, which at different times of year may comprise grasshoppers, seeds, caterpillars or fruit. This led them into conflict with European settlers whose farms they seemed to threaten. In Western Australia the Great Emu War of 1932 was fought between migrating mobs of over 20,000 emus, and the Australian army with machine guns and grenades, called in by the state government. Jock Marshall in his pioneering conservation work The Great Extermination reports "History does not record the name of the CO emus, but he must have been a good chap". It seems that perhaps only a dozen emus were killed, and the government had to withdraw the military to save them from further embarrassment.

Unusually among birds Emus are polyandrous - ie one female, several blokes. In June (early winter) she lays up to 20 dark green eggs in a scrape on the ground; each can weigh three quarters of a kilo, so the cost is immense. Understandably, she plays no further part in the chick rearing, but if she feels so inclined she can go off and do it all again with someone else.

Emu nest, south-west Queensland.

He sits on the eggs for eight weeks, in a semi-torpor to save energy, living off his fat reserves without eating, drinking or defecating, but turning the eggs over at regular intervals. In the south-eastern high country this also meant being covered in snow at times.

The stripey chicks can walk within hours of hatching, and run and swim in a week.

Emu chicks near Cue, Western Australia.

As they get older they lose their stripes but can still be distinguished from their father by their dark heads and necks.

Immature Emus, Currawinya National Park, Queensland.

He looks after them for 18 months, so he only breeds every other year; the female of course doesn't have that restriction.

A familiar night sound to campers in 'the outback' is the resonant booming of Emus, enabled by a unique cleft and an inflatable pouch in the trachea. It can be heard up to two kilometres away.

Another characteristic is the feathers; haystack-like, they seem to have no cohesion, and indeed they don't. Unlike more modern birds they don't have barbules to lock the feathers together; further, the aftershaft, which forms a woolly base to feathers in most birds, is the same length as the main shaft in an Emu, so the feathers appear to be double.

Emu plumage, which characteristically flops about while it is running.

Emus are in some ways the archetypal Gondwanans (ignoring the prevailing view of their intellectual powers!); they are ancient and very special.

BACK ON MONDAY

I think it's time to introduce another chapter in our intermittent discussion of Colours in Nature - you can find the others from that most recent one. As soon as I started preparing for some musings on blue in nature, I realised that yet again one posting wasn't going to nearly cover it. At this stage I anticipate two on animals and one on plants, but I've been wrong before...

It is a bit of a shock to realise that it's becoming increasingly likely that there are no blue pigments in any terrestrial vertebrates! As I suggest in the title it's all a trick, by an array of complex structural mechanisms wherein small 'bubbles' in skin or feathers or shell allow longer wavelengths (reds, oranges, yellows) to pass through but are of a size to 'trap' shorter wavelengths - specifically blues - and reflect them back to us. The principal is known as Tyndall scattering after 19th century Irish-born British physicist John Tyndall who described it; the effect is often seen with very fine particles suspended in liquid, such as very fine silt in rushing streams or the iris of a blue eye. There are variations too, but this isn't a physics blog...

Male White-winged Fairy-wren Malurus leucopterus, north-western New South Wales.

The male White-winged Fairy-wren, sitting up on a saltbush in its vast plains habitat, shines like a light. However if you were to find a shed feather, and crush it, you'd find it turned from shining blue to a indeterminate dirty-whitish, as the crucial little bubbles were broken. Let's just admire a few of the results of this extraordinarily subtle and precise application of wave physics in the feathers of some of the most glorious birds I've seen. Some, like the wren above, are mostly blue; others feature blue highlights that stand out from the surrounding contrasting colours.

Crimson Rosella Platycercus elegans on Banksia integrifolia. This is one of the commonest and most familiar bird species around here, but I reckon that the day I get bored with them is the time to hang up my binoculars.

Swift Parrot Lathamus discolor, by contrast one of the rarest of parrots and a listed threatened species; there may be only 1000 wild pairs left. They breed in Tasmania and every autumn cross the Bass Strait to over-winter in the woodlands of inland south-eastern Australia, including around Canberra. This one was part of an influx to Mount Majura on the edge of Canberra couple of years ago. The lovely sky-blue wing patch and forehead are really only visible when the bird is perched close by - something they don't do very often!

Azure Kingfisher Alcedo azurea, Barmah Forests, Murray River, Victoria.
Every unfrozen continent has blue kingfishers, but I reckon this one is as brilliant as they come.
And not a drop of blue dye involved...

Red-and-Green Macaws Ara chloropterus, Blanquillo clay lick, Peru.
I've never understood why the green was selected above the blue for the name, but I guess either would have been inadequate alone.

Abyssinian Roller Coracias abyssinicus, Waza National Park, northern Cameroon.
A resident of the vast arid Sahel woodland strip, south of the Sahara,
its blue is displayed in contrast to the earth-brown back.

Turquoise Jay Cyanolyca turcosa, Bellavista Lodge, Ecuador.
Northerners are used to brilliantly coloured crows - of which the jays are surely pre-eminent - but in Australia we only have the black Corvus crows, so we're a bit jealous. (I say 'northerners'; although there are several jay species in South American rainforests, they only arrived there relatively recently from the north when the Isthmus of Panama joined the two American continents.)

Masked Tanager Tangara nigrocincta, rainforest canopy, Sacha Lodge, Ecuador.
The tanagers have among the widest colour ranges of any bird group; blue of course features.

Masked Flowerpiercer Diglossopis cyanea, Yanacocha Reserver, Ecuador.
A group of tanagers, the flowerpiercers make a living by 'cheating' flowers, cutting the base to obtain nectar without offering any pollination services. Blue is a favoured colour among them.

So far, all of these blue birds look uniformly blue no matter how you look at them, as you might expect. However that is not true of all blue birds by any means.

Male Satin Bowerbird Ptilonorhynchus violaceus, Canberra.
From some angles he can look dull black, then suddenly he turns and flashes deep glossy blue.

This is iridescent colouring, and the principle is different from non-iridescent colours. Here the thin surface of the feather is transparent, but beneath it is a layer of melanin. Some light reflects from the surface, more of it bounces back from the melanin layer; if the waves coincide, peak to peak, the colour is dramatically emphasised, but if peak and trough are adjacent the waves cancel each other, and the feather appears black. From one vantage point the effect is consistent, but as the observer and the feathers move, the angle changes and so does the colour. In the bowerbird above, his front half looks blue but the rest seems black; a second later and the the effect could be reversed. The actual colour is determined by the depth of the melanin layer, which decides the wavelength of the reflected light.

Here are some examples.

Leaden Flycatcher Myiagra rubeculamale, National Botanic Gardens Canberra.
This one took me by surprise; normally he is a dull leaden grey, but he suddenly caught the sun and lit up.

Ethiopian Swallow Hirundo aethiopica, Waza National Park, northern Cameroon.
Many swallows demonstrate a blue iridescence on the back. It's been suggested that the 'flash and vanish' effect in flight confuses predators.

Cape Glossy Starling Lamprotornis nitens, Etosha National Park, Namibia.
Some starlings are among the most dramatic of iridescent birds. Even they however, cannot outdo the hummingbirds...

Great Sapphirewing Pterophanes cyanopterus, Yanacocha Reserve, Ecuador.
It was hard to pick just one iridescent blue hummingbird, but this is a pretty good representative.

There are of course iridescent feathers in many other colours, but that's another story (and one which will be told, in its time).

That's also enough for today, but next time I want to explore other blue body parts - skin, scales, beaks, legs, insect wings etc. That one threatens to be even longer than this one...

BACK ON WEDNESDAY

As promised in the last posting, I'm going to continue talking about beautifully blue animals and, as in our exploration of blue feathers, virtually none of the sky-coloured feet, beaks, skins, and insect parts that follow have any blue chemicals to thank for their hues. All are due to scattering of light by fine particles suspended in liquids, or by carefully ordered layers of collagen fibres, or thin layers of scales precisely spaced, or parallel ridges that reflect and emphasise blue light. The physics of most of it is beyond me I'm afraid - fortunately this is not a physics blog! However if you're mathematically minded, this might be of interest.

Bearing the general principles in mind, here is a tour of some of nature's blue bits.

Poison Dart Frog, family Dendrobatidae, Ecuador.
(Don't try this at home, or anywhere else, incidentally! Local people seem to acquire an immunity to these stunning but potentially deadly little frogs. I've heard of visitors getting very sick from handling one.)
Frog skin colours are very complex, with often three layers of different cells in the skin. In the case of blues, iridophores sit above melanin-filled melanophores; the iridophores reflect blue light back, like iridescent feathers that we discussed last time.

Reptile scales can be similarly constructed, to produce blues that can often be switched on and off by contracting the melanin cells below the light-scattering layers, especially in the case of displaying males.

Male Gippsland Water Dragon Itellagama (Physignathus) lesueurii, National Botanic Gardens, Canberra.

Unidentified skink, Cooktown, north Queensland. Any assistance gratefully received!

Male agamid, Queen Elizabeth National Park, Uganda.

Blue skin in mammals and birds is caused by arrays of collagen fibres, again above a melanin layer. I don't have pics of blue mammal parts (the best known of which are probably Mandrill faces and backsides, and the scrotums of Vervet Monkeys; oh well, I don't want to alarm your family filters anyway).

Southern Cassowary Casuarius casuarius, Wallaman Falls north Queensland.
(Taken through a car window!)

Blue-faced Honeyeater Entomyzon cyanotis, Griffith, New South Wales.

Blue feet are very popular in one bird made famous by wildlife documentaries. Here it's just the skin again.

Blue-footed Booby Sula nebouxii, Puerto Ayora, Galapagos.
The bluer the feet, the more attractive the owner to the only one who matters.

A bird's beak is covered with a thin layer of keratin rather than collagen; I can't find much about the role of keratin in producing blue beaks, but I see no reason why it wouldn't be a similar story to the collagen structures in skin.

Andean Ruddy Duck Oxyura jamaicensis, El Calafate, Argentina.

White Tern Gygis alba, Lord Howe Island.


Dusky Woodswallow Artamus cyanopterus, Canberra.

And of course there are numerous invertebrate examples.

Leaf Beetle, Chrysomelidae, possibly a cryptocephaline (the cylindrical leaf beetles) Whyalla, South Australia.
I have no idea about this beautiful chewer in particular, but in some blue beetles at least layers of disc-shaped scales in the cuticles are responsible.
(My thanks to Susan for helping with the family.)

In grasshoppers, the mechanism is apparently again a suspension of granules in the cuticle, above a dark background; I assume that this is how it works in this wonderful beast, but I don't know that it's been investigated.

Painted Locust Schistocerca melanoceraSierra Negro volcano, Galapagos.
Like so many other Galapagos residents, they are found nowhere else.

In dragonflies, the system is similar, with Tyndall scattering of light from particles suspended in a waxy layer above a dark cuticle layer.

Tropical Rockmaster Diphlebia euphoeoides, north Queensland.

Black-headed Skimmer Crocothemis nigrifrons, Canberra.

And of course numerous butterflies and moths flaunt blues, with a variety of variations on the themes described above, involving precisely spaced layers of scales. Some members of Papilio and Graphium swallowtails actually do have some rare blue pigments, but even these are emphasised by scale orientation.

Shining Oak Blue Arhopala micale, Cairns, north Queensland.

Satin-Green Forester (Pollanisus viridipulverulenta, Yeldulknie Conservation Park, South Australia.
Its iridescence makes it flash from green to blue, depending on the angle. Don't sniff too deeply - its family, Zygaenidae, specialises in releasing cyanic acid in self-defence!
(My thanks to Susan for putting me on the right track to identifying this one by recognising the family.)

Urania Moth, Manu National Park, Peru

Euchromia creusa, north Queensland. Here the blue is not (mostly) in the wings, but in body scales.
Presumably the principle is the same however.

Finally, to a couple of animals which probably do have pigments - many marine animals do, including crustaceans, and I see no reason why these crabs would not.

Sally Lightfoot Crab Grapsus grapsus, Galapagos.

Soldier Crabs Mictyris longicarpus, Cullendulla Creek Nature Reserve, New South Wales

Well I'm about blued out for now, but I've enjoyed the journey; I'd love to hear if you have too, or if you have any comment to make. We're still to talk blue in plants, but we might have a break from blue before we tackle that one.

EITHER WAY, BACK SUNDAY

Lake Mburo National Park was the last park I visited in a very memorable trip to Uganda (mostly birding, though by no means just that) a couple of years back. It wasn't the most dramatic place I saw, but I have good memories of it, along with a tiny frisson when I think of the pre-dawn walk on my own to breakfast, wondering how far the lions had moved on!

It is in the far south-west of Uganda, in the savannah country, focussed on big Lake Mburo, part of an extended wetland system.

The accommodation was relatively simple, in comfortable permanent tents on wooden platforms, perhaps my favourite of the trip - I always sleep best in a tent!

My tent; note the shower system to the left. On request it is filled with warm water; the flow is regulated from
inside by pulling chains to turn it on and off. Very sophisticated I thought!

My verandah; a most pleasant place to sit, read, write and contemplate.

The view from the verandah. over the low woodland to the distant lake in front of the hills.

Uganda's parks suffered terribly in the Amin years, with most big mammals being shot by troops for food and entertainment. They are recovering very well now though, and we were warned to be wary of buffaloes wandering the unfenced camp. Seeking some reassurance, if I'm truthful, I asked Alex, my 'house attendant' "When I go to breakfast in the dark tomorrow [a 300 metre walk on paths through the scrub] is it dangerous?". "No, it is not dangerous." "Are there no buffaloes then?" "Yes, there is buffaloes." There seemed nowhere for the conversation to go after that...

We had been told that neighbours had shot out the lions from Mburo, but were pleased to hear distant roaring on the first evening.The at about 4am I heard a party of lions coughing and growling nearby; the tent suddenly felt very flimsy. It was not a totally relaxed walk to the nice open-air dining room a scant couple of hours later.

Camp dining room.

A highlight was a boat ride on the lake, where Finfoot was a high priority for me. Bingo, as soon as we arrived!

African Finfoot Podica senegalensis, early morning Lake Mburo.
This is an intriguing species whose only relatives seem to be the Masked Finfoot of south-east Asia
and the South American Sungrebe.

African Fish-Eagle Haliaeetus vocifer Lake Mburo.
Their pulsing whistling duets are one of the most evocative sounds of Africa.

Malachite Kingfisher Alcedo cristata; no matter how often I see this little jewel - and it is widespread across Africa - it is never enough.

Parks staff washing vehicles in the lake - and yes, there are crocodiles here!

A walk in such areas is not the same as a walk in Australia, where nothing is likely to stand on or gore you with malice aforethought. As we ventured into the edge of a swampy area (putting our faith solidly in the hands of our Ugandan guide) a distant group of buffalo and we viewed each other suspiciously, but we each kept our respectful distances.

Swampy habitat, Lake Mburo.

Saddle-billed Stork Ephippiorhynchus senegalensis, a magnificent big hunter of fish and frogs,
and a close relative of the Australian and Asian Black-necked Stork.

Greater Blue-eared Starling Lamprotornis chalybaeus; the magnificent glossy starlings of Africa constantly delight me.
In southern Australia the only starlings are two highly destructive exotic species,
which can't provide much satisfaction here.

Mburo's mammals are another source of great pleasure, with zebra and antelopes prominent.

Plains Zebra Equus quagga, common in Lake Mburo. A small group accompanied us into camp on the first night, perhaps nervous of lions and glad of our temporary protection. The extinct Quagga and the Plains Zebra are now considered the same species, and as the Quagga was named first its name takes precedence.

Impala Aepyceros melampus, truly a most elegant antelope.

Waterbuck male Kobus ellipsiprymnus; another typical Lake Mburo resident.
A powerful antelope, rarely found far from water.

Lake Mburo is a highly recommended part of your visit to Uganda, a country famously described as 'the pearl of Africa' by Sir Winston Churchill. Certainly recommended by me anyway...

Sunset, Lake Mburo National Park.

BACK ON WEDNESDAY

This is the story - or rather two stories - of two very different groups of tropical rainforest ants, in two continents, which have in common only that they do remarkable things with leaves, and are the basis of two pretty good yarns.

Leafcutter Ants, Yasuni National Park, Ecuador.
There are over 40 species of leaf-cutters in the genera Atta and Acromyrmex, found from southern North America through Central America to much of South America; the differences between the genera (not to mention the species) are really only available to laypeople with a good lens and an immobilised ant!

Green Tree Ant Oecophylla smaragdina, Litchfield National Park, south-west of Darwin, Northern Territory of Australia.
This species (as currently recognised) is found across the coastal tropics of Australia and through south-east Asia to India. Only the Australian ants have the green abdomen; elsewhere they are known as Weaver Ants.
There is also an African species, O. longinoda.

Anyone familiar with the Australian tropics is very wary of Green Tree Ants; it is easy to inadvertently annoy them by leaning on their tree, and it's something you don't do twice. They don't have a sting, but they can bite hard enough to break the skin - after which they make sure they have your attention by spraying the wound with formic acid. It works too. On the other hand there seems to be no consensus about the stinging capabilities of the Leafcutters; different sources are equally adamant that they either do, or cannot, sting - perhaps it varies between species, or genera. There seems to be an agreement that they can bite however, though I've never had a problem with them, and the lodges in the Amazon which have trails of them on the paths don't see the need to warn guests about them.

They both utilise leaves, but in entirely different ways and for quite different purposes. The Green Tree Ants glue living leaves to make a magnificent nest.

Green Tree Ant nest, Darwin. The 'glue' can be seen as white material at the bottom of the nest.

I've never seen the beginning of construction, but it's commenced by a few ants reaching across from one leaf to another to pull them together by sheer force. If the process looks like being a success, more ants join in - the more ants that are involved, the more likely it is that others will assist. If the gap between leaves is too wide the ants will form a living chain to bridge it. Once the leaves are in contact something even more remarkable happens. Other workers bring mature larvae, and with their antennae signal them to start releasing their silken threads from glands below their jaws; they move the larvae back and forth like glue guns.

A colony may number half a million ants, and maintain well over 100 nests in 20 or more trees. Green Tree Ants are voracious scavengers and hunters, streams of workers bringing back a variety of animal food for the queen and larvae; workers lay chemical trails to lead others to a good source.

Green Tree Ants dismembering a dragonfly, Litchfield National Park.

Leafcutter ants on the other hand do not eat meat - but despite the evidence of our eyes, they do not eat leaves either!

Leafcutter Ant trail, Manu, Peru.
These trails of ants carrying leaf segments above their backs as long as the sun lasts
are an integral part of South American rainforests.

Given their ability to cut leaves all day into manageable pieces, it's not surprising that they're reputed to be able to give a respectable nip if molested. The leaf material is taken to the nest, cleaned and taken to the underground fungus farm, where they are used to feed a remarkable species of fungus, which has lived in ant nests for so long that it has lost the power to produce spores to reproduce (according to at least one source anyway). The entire ant colony lives on the nutritious fungus.

Nor do all leafcutters restrict themselves to leaves!

Some plants produce leaves which are inimical to the ants, which avoid these trees. If they do bring an undesirable leaf home they are able to monitor the fungus' reaction and remove the offending greenery again.

The nests are enormous and may cover tens of square metres of forest floor, which the colony keeps clear of vegetation.

Leafcutter Ant nest, Manu, Peru.
A big colony can house millions of ants.

When a queen leaves to start a new colony she takes a fungal sample with her to start the new farm. These young queens emerge in vast numbers, a resource large enough in Ecuador to attract the Quechua people to collect them, wrap them in leaves, and sell them in markets.

Leafcutter Ant queen, Sacha Lodge, Ecuador.

I am always fascinated by ants, but the activities of Green Tree Ants and Leafcutters constantly astonish me, and they are one of the first things I look out for when I get back to the tropics. If you've met them, I hope this brings back good memories; if you haven't, that's something for you to look forward to!

BACK ON SUNDAY

This is an 'out of session' post to draw your attention to another project of mine, a periodic series of reviews of natural history related books, which I email, but which are also posted on the National Botanic Gardens Botanical Bookshop website. You'll find the most recent one, as well as all previous ones, HERE.

Meantime, here's a small offering for your trouble.

Young Marine Iguanas on jetty, Isla Isabela, Galapagos.

BACK ON SUNDAY

Wildlife of the National Botanic Gardens

Kosciuszko National Park #1: on top of Australia

Kosciuszko National Park #2; to tree or not to tree?

Kosciuszko National Park #3; some inhabitants

Huntress in the House

Red, Black and Conspicuous

Seeking Hides

Oddbills 3

From Monga to Gondwana (via some orchids)

Walking the Malabar Cliffs; the end of Lord Howe

Eurobodalla Regional Botanic Gardens; treasure at the coast

March of the Orchids

Meet the Great Greenhoods!

Flood Bugs on the Move

Musing on Emus

The Blues; nature's trompe d'oeil #1

The Blues: nature's trompe d'oeil #2

Lake Mburo National Park

A Tale of Two (Ant) Cities

Natural History Book Reviews