Possum twins

The female Common Brushtail Possum Trichosurus vulpecula which lives in our back garden,

 with a single youngster

October is the time for the local brushtail possums in Canberra to be carrying their large young around. We have two females in our garden, shared with our human neighbours, and they both have young. One has the usual single youngster, but the other has twins, which is uncommon. It seems that it is also rare for both young to survive. However, these twins seem to be growing well and it looks like they will both survive.

The neighbouring female in the front garden walking across the drive with her twins on her back

I often go out at night watching for wildlife, and it is noticeable how I have spent hours in the local woods and only seen a few possums in that time. Then when I walk back through the adjacent suburbia, I seem to see a possum in every other garden. This and the set of twins (I have seen possums with twins in the garden before) are signs that there is good feeding to be had for possums around humans. They are one species that is a successful urban survivor.

Doubled up on top

The youngsters have a yellow/orange tinge to their fur which gradually fades to the grey of the adults, as can be seen by the difference in colour between the larger and smaller twins.

The twins are growing fast and putting on weight

The twins can climb already as I have watched them follow their mum as they walked along the branches, but they still take the easy option and travel on their mother's back whenever they can, which is still most of the time. I think that will soon stop.

There is no easy way to climb down a tree with twins on your back

Especially if they make climbing difficult for their mother, for such encumbrance would in  the long run make the whole family vulnerable to predators. So the next stage of evolutionary behaviour will kick in soon and they will have to become more independent. Then we will have three more possums galloping across our roof at night. Mmmmmmm, a bit noisy.

Those prehensile tails can be a nuisance sometimes

Frogmouths incubating

A pair of Tawny Frogmouths Podargus strigoides at their nest site - can you spot them

September is the month when most tawny frogmouths in the Canberra area lay their eggs and begin their four-week incubation. This year, the earliest birds laid on the 26th August and the last ones have yet to lay, which is typical of the spread that I have found in the past several years. I monitor about fifty pairs in my studies of these birds, and they are rather difficult to find as they are well concealed. Yet every time I do find a pair at their nest site I cannot help but admire their adaptation to their habitat.

The male sitting on the nest set in the fork of a tree - tricky to see in the typical dappled light

The male incubates the eggs during the day while the female sits quietly in a nearby tree. Neither will move when approached apart from shifting their posture, usually to an erect stretched pose by which they blend into the shape of a branch. As their colouring also resembles that of a dead branch, they simply disappear into the wood.

The female sits on a dead branch high in an adjacent tree

The dead branch posture is the one most people are familiar with if they come across a bird, but most of the time they sit fluffed up and bask in the sunshine. Some of the birds I study are familiar with me as I have visited them several times a year over the years, they probably recognize me. And it is probably because the birds have seen me so often that they do not go into their branch pose. I have been right next to birds as they have cocked their head right back and opened their feathers to catch the sun. I always prefer to study undisturbed birds so it is especially pleasing to be accepted as not a threat by a wild animal.

A female basking in sunshine, with loose feathers and head tilted to catch the sun

A female adopts the stick-pose, where she resembles a dead branch in colour and shape

As a little footnote, not all the birds build their nests in a branch fork, some use old nests of other birds. And a favourite old nest is that of the white-winged chough. These are mud nests, set half-way along a lateral branch and the frogmouths add just a few sprigs of leaves and twigs to the cup of the mud nest. This might give the birds a more secure nest site than the usual flimsy loose platform balanced in a fork, but they are more obvious to predators. Over the years, I'll gather information on whether the birds that use old chough nests are more or less successful at rearing young than those that use conventional nests.

A Tawny Frogmouth sitting on his nest in an old White-winged chough Corcorax melanorhamphos nest

Dry woodland orchids continued.....

Wax Lip Orchid Glossodia major

There seem to be more and more orchids coming into bloom every day at the moment in the Canberra woodlands. Today the forest floor was peppered with blue dots of wax lip orchids in numerous colonies. The blue of these flowers is so intense, and really emphasised, by the the grey leaf and bark litter that they grow amongst. Although they are not as obvious as would seem as the strong sunshine bounces off the ground cover, making it difficult for human eyes to discern the colours in the brightness.

Dry woodland orchid habitat in Canberra 

Also, the orchids are only about 20cm tall, shorter than the grasses, but as one walks through the grass, the flowers appear into view on looking down into the sward. One after another.

A cluster of three Wax Lip Orchids - two still in bud

The most I saw in any one cluster was perhaps seven or eight, but the clusters are only part of larger colonies of twenty, forty, or more flower spikes. Then there will be a gap of a few hundred metres before another colony appears out of the grass.

A typical view looking down on these forest-floor orchids

The other orchid species I saw today, but not previously this year, was the brown caps. There were fewer of them showing and being white, they were probably less noticeable. All the more rewarding to see.

Brown Caps Orchid Caledenia ustuluta

This group were growing on the top of a gully bank, between low-lying shrubs and if not in flower they would be difficult to pick out from the foliage.

Profile of a Brown Caps Orchid flower

The detailed structure of orchid flowers are famous, and bewildering in their variety, with each feature having evolved for a reason to help the species cross-fertilize. They are fascinating when viewed up close, singly or in multiple flower-heads on one stem. No wonder they have so many human admirers.

A stem of Brown Caps Orchids with four flower heads 

Finger orchids

Blue Fingers Cyanicula caerulea - whole plant

The Spring orchids are coming into flower in Canberra and although some can be difficult to find, these finger orchids are obvious. Despite their short stature, only about 10cm tall, and growing singly, these little gems are easy to spot as the forest floor is studded with their flower heads. These flowers were on Black Mountain in the heart of the Australian Capital Territory, only a few kilometres from the city centre. Both species shown here were growing on thin stony soils in the dry forest beneath scribbly gums and red stringybark trees, with sparse leaf and bark litter. Other ground cover was mostly sparse tussocks of wallaby grass.

Blue Fingers Cyanicula caerulea - flower head

The flowers were of three colours, the blue of the blue fingers, and white and pink - two colour varieties of the dusky fingers. All the flowers were fresh and bright so they could not have been long opened. The other species I saw that day was nodding greenhood Pterostylis nutans a tiny flower of a few centres tall that was growing in a compact colony on the steep moist bank of a dry creek. Some of those flowers were fading, while other plants had not yet flowered. The season has been slow to warm up with cold spells, so perhaps that has affected their flowering. To see images of them from an earlier post click here.

Dusky Fingers Petalochilus fuscatus - whole plant

The blue fingers have prostrate single leaves, while the dusky fingers have erect lanceolate leaves as seen in this photograph of the white variety.

Dusky Fingers Petalochilus fuscatus - flower head, white form

Dusky Fingers Petalochilus fuscatus - whole plant, pink form

Dusky Fingers Petalochilus fuscatus - pink flower head

Dragon fight

Two Common Bearded Dragons Pogona barbata face one another off

The reptiles in Canberra are becoming more active every day as the weather warms. I found a gecko on the front doorstep this morning and a blue-tongued lizard has taken to sunning itself on the edge of the drive. Then while out in the woodlands I came across these two bearded dragons fighting in the middle of the path.

The dominant dragon gains the high ground

I stopped and watched them from a few metres off to follow the outcome, although by the time I found them they appeared to have settled most of the dispute as one seemed to be dominant and the other subordinate. The dominant dragon was circling around the other, always clockwise, spreading out his body and tilting it to show a broad back artificially widened, with spines along the edges. And he blew up his throat to make that look large, again with spines frilling the edge. Meanwhile the subordinate dragon lay low, with its body held slim, his throat non-extended and spines held close, but still showing his teeth and in his bright yellow mouth as if ready to defend. The two, reminded me of red deer stags rutting, facing off to one another, adopting postures that threaten, by exaggerating their size and height.

The inside of their mouths is bright orangy/yellow
 which I am sure when seen from close contact is a formidable threat display

They fought for several minutes, strutting, biting, chasing and tumbling into the grassy verge, knowing I was there, but ignoring me as they were locked in a combat each wanted to win. Then it soon became obvious that one had won the contest. He held his head high and the other lay low. As with stags, they seemed to hold back from inflicting serous injury to one another. Each had a few scales knocked off and even the winner had a bloody smear below one eye. The two seemed evenly matched in size, about 500mm long, and neither looked stronger to me, so how the contest was decided I do not know, strength in endurance perhaps.

The victor posed with head up high and his throat inflated

The loser cowered low with his spines retracted and body held thin

I photographed a more aggressive fight back in 2011, to see those shots follow this link:

In the end, the loser lifted up on his hind legs and ran into the bush, spreading out his belly and neck to look big from behind - a final act of defence in case the other dragon might still attack.

Warming up

A Gippsland Water Dragon Physignathus lesueurii howitii sun-basks on a rock

The days are lengthening and warming up now in Canberra and the reptiles are beginning to show themselves. There are various species of skinks basking on the rocks in our garden, they are little animals of only several centimetres in length, but while at the Botanic Gardens yesterday, I photographed this metre-long water dragon. By its colouring this one looks like a youngster turning into adulthood - its back is more green than dark brown or grey, and there is some yellow coming through on its throat. Full adults have a pale but true green skin and a fully orange/yellow throat.

The throat was blotchy yellow

I only saw the one dragon and it was very approachable. A sign that it was still early Spring and the group that usually frequent the pool where this one was basking next to had yet to get going for the season.

The dragon was lying flat and tight against the rock it was lying on, making maximum use of the warmth of the rock by contact as well as catching as much direct sunshine/heat as possible. The hind legs are turned out wide and it was orientated along the line of the sun, with its shadow falling off under its chin. A well-adapted piece of animal behaviour.

These dragons are found in and near water around the Canberra area, and throughout south-eastern New South Wales and Victoria. There is a colony of them living in the Gardens, around the ornamental pools. They are much more approachable than those in wild settings, where on approach, they will run and dive straight into the water and remain submerged until any threat of danger has passed. Some of their dives can be rather dramatic as they will also climb trees and will dive into the water from the branches if disturbed.

A true dragon - with a magnificent line of nuchal spines running down the back of its neck.

So I took my chance and grabbed some nice close up shots of the dragon features: the scaly lips, the nuchal spines (elongated and enlarged scales on the neck) and that magnificent dragon's eye.

A dragon's eye

First day of Spring

Apricot blossom

Today, the 1st of September, is the first day of Spring here in Canberra and the garden is full of activity. The new growth is bursting from the plants and I saw the first butterfly of the season, a cabbage white. The skinks are sun-basking on the rocks and the crested pigeons are collecting nesting material.

But the best show is the blossom in the orchard. The apricots are always first to open and there is a terrific amount of flower heads, so lots of fruit in late summer if all goes well, and the rosellas don't eat too many buds. The plums are a few days behind, but the apples are still in tight bud.

A honey bee approaches the blossom

As it was the first day of Spring I thought I should capture the flavour, so grabbed a few shots of the blossom, then focused on the honey bees as they busied themselves around the blooms. Or rather, I tried to focus on them. They fly so quickly and being so small, there isn't much insect to focus on. But here are a few shots which I took at 40000 - 64000 ISO, 1/4000-1/8000 sec.

Bees are such wonderful fliers

If it takes such high speeds to freeze their movement (except their wing beats), I wonder what speed their own perception operates at, they must live fast furious lives.

And they make apricots for me..., the family, the neighbours, friends; the trees bare so much fruit every year we need to share.

Pollen sacs filled , maybe one little bit more...

Prospecting ducks

A pair of Australian Wood Ducks Chenonetta jubata above a potential nest hole high in a tree

It's not only parrots that nest in tree holes in Canberra, although there are so many around it seems like it sometimes. Tree holes are prime real estate for a many animals; brush-tailed possums and sugar gliders, kookaburras and treecreepers, bats and smaller creatures such as spiders. Also, as Canberra has lots of open grassland in parks and road verges, it has a large population of wood ducks, which are grass-eaters. And they all need nest holes too.

The other day I watched a female wood duck cooing and grunting from high in the branches of an old eucalyptus. She was prospecting for a nest hole and seemed to have found a suitable one if only she could work out how to fly into and land on its rim - the hole was on the underside of a thick limb.

The female was the more interested in the hole, the male was simply following her, protecting her

She spent more than ten minutes bending over and peering into the darkness, while the male spent most of that time preening himself. The drake's purpose is to protect his mate from predators and any other suitors. So, this one's investment is in her and the fertilised eggs she was carrying. Her investment is a safe place to nest, hidden away from danger while she incubates the eggs. She will be in her nest hole, whether this one or another, for about a month, only coming off perhaps once a day to feed. Then when the ducklings hatch, she will encourage them to jump down from the nest hole, then lead them away to the nearest water for safety, and surrounding grass for the ducklings to eat.

She seemed to like the hole but wasn't sure how to get into it?

Spring Plumage

Diamond Firetail Stagonopleura guttata in bright adult breeding plumage

Spring is ever nearer in the south-east Australian bush and many of the birds, especially the passerines, are beginning to breed. Which means that they are now in full breeding plumage and looking their best.

Over the past weekend I was part of a team mist-netting birds at The Charcoal Tank Nature Reserve in south-western New South Wales, as part of a long-term study of birds in the area, organised by Mark Clayton. And it was clear by the condition of the birds' plumages that they were fit, healthy and ready to breed.

Diamond Firetail 

There was a flock of Diamond Firetails feeding on grass seeds along the edge of the reserve and they were dazzling as their red rumps flashed through the grasses. The bird shown here is an adult in full breeding plumage, with all the feathers on the head and breast clean and fresh. For these are the feathers which any potential mate or competitor would see when assessing its fitness. However, the flight feathers, the primaries secondaries and their coverts were a bit tatty, with chips and worn edges. For these feathers would have been moulted and re-grown at the end of the previous breeding season, and they will be again at the end of the current season, but for now they are still perfectly functional and there is no need to replace them yet. Birds are almost constantly moulting part of the their plumage at any time of the year, and for the moment it is the bright signalling feathers that need to be in top condition.  

White-plumed Honeyeater Lichenostomus penicillatus

It is not only their feathers which are spruced up for breeding. The white-plumed honeyeaters which we caught, also adopt shiny dark colouring to their bills - they are duller and greyer when not breeding. This adds impact to their dark eye and the slight fringe of dark feathers on their neck, next to their white-plume, which the dark colouring emphasises. By the time the birds are half-way through the breeding season, the best of these colours will have begun to fade.

Chestnut-rumped Thornbill Acanthiza uropygialis

Even the little-brown-jobs, the small dull coloured birds adopt brighter plumage. This chestnut-rumped thornbill had a particularly well marked face pattern, in relative terms, and it's only when we see them up close, in this case in the hand while ringing/banding them, that we can appreciate the detail of these tiny birds' markings. Although to a bird's eye, they see things across a wider spectrum than us, these markings probably also signify the birds health, fitness and hierarchy in the flock, only more demurely.

Chestnut-rumped Thornbill - face

The sexes of all three previous species have similar plumages to one another of their species, they are monochromatic to our vision - but probably not to their own. For birds can see ultra-violet colours and in some species this has been found to be used in their markings to differentiate between the sexes. Do these species sport such colouring?

Golden Whistler Pachycephala pectoralis - male

Some of the brightest birds in the study were the male golden whistlers, and if their plumage is enhanced with ultraviolet colouring they must be amazing to see through a whistler's eyes. This species is dichromatic - there is a colour-difference between the male and female. The female is an almost overall grey colour, which is fit for purpose, as she incubates the eggs and broods the young. That involves a few weeks of her life each year, spent sitting on a nest set amongst grey-barked branches, so the grey colouring acts as camouflage while she is on the nest. The species has evolved for the females to be camouflaged while the males are brightly coloured to show off their fitness and hence value for a female to mate with, or for another less-brightly coloured male to avoid.

Even in her grey plumage, the female can be seen to be healthy and fit to breed as her feathers are clean and fresh. She too is fit to breed.

Golden Whistler - female

Snuggled up

It's late winter in Canberra with frosty nights and sunny days, and the birds are beginning to show springtime behaviour. The Tawny Frogmouths are drawing closer to their breeding sites, moving in from more distant perches to be close to their nest sites. They will be building their nests soon. Although none have started to do so yet, I have seen birds with well-built nests by this date in previous years, with the earliest eggs laid on the 12th August. Meanwhile, they are making the best use of the sunshine as they roost during the day.

A pair of Tawny Frogmouths Podargus strigoides roost by day in a gum tree
the smaller female sits closer to the trunk as is usually the case - for protection by her mate?

They are medium-sized birds, about the size of a Tawny Owl, and live mostly on invertebrates. However, they have a slow metabolism and as insects and such creatures are not abundant during winter, they move as little as possible, slow down their metabolism even further and sit in sunny situations, all to conserve energy. And to do so while daytime predators are about, they have evolved excellent camouflage for protection.

A pair of frogmouths sit high on a sunny branch

Yet, they don't stay completely motionless all day. This pair mostly roost farther along the branch towards the trunk, but as the sun has crossed the sky, they have shuffled along the branch to stay in the sunshine. Today was cold.

The spot where these birds usually sit is farther to the right, as can be seen by the worn red bark on the branch and a fluff of cast down below where they normally sit.

The frogmouths sit fluffed up and huddled into a rounded shape to keep warm, and by snuggling up close to one another the pair gain extra warmth.