Sunday, 30 December 2018

Fantastic Phasmid

This Titan Stick Insect Acrophylla titan was in our garden yesterday, he probably still is, but I can't see him. His two long antennae are tucked in between the front legs, which have a ragged, leaf-like form.

The thorax and legs had thorn-like spines which also made him resemble a true twig.

Acrophylla stick insects are well named as they favour the highest foliage of eucalyptus trees to feed on, acro being Greek for highest or topmost. So I don't know why this one was down in at our lowly level. The tall yellow box in the front garden, which spreads over where he was hiding, is about 20 m tall. He was about 20 cm long.

His eyes had cryptic colour bands around them, and there was a tiny mite clambering around them.

Seen from below, his head was just as spectacular, with an intriguing array of mouth parts. Why does a vegetarian need such a complicated eating system, I wonder. They only eat leaves.

His wings are on the last section of the thorax, but extended over the fore part of the abdomen. The vestigial wings on a female only extend as far back as the last pair of legs. Although his wings are small for his size, the males can fly. The females cannot. I think this one must have flown away as I left him in one small tree and after dusk he had gone, not in the tree. And yes I am sure he wasn't there. They are nocturnal feeders.

And look at those fantastic feet. He has two hooks and a gripping pad on each one, so over six legs, that's a lot of sticking ability. No wonder they are such good climbers and like to be high.

Friday, 14 December 2018

Big rain

Droplets of rain hang from eucalyptus flowers in the garden. 

More than 50 mm of rain fell on Canberra yesterday, 29 mm before 0900 hr and final figures not in yet. A great relief after such a long dry winter and spring, but I would rather less fell more frequently to give the land a chance to re-invigorate itself, the plants to grow and animals to prosper. Too much rain at once is of limited good.

During a break between the heaviest downpours, the water clung tight, running slowly down the long tapering leaves.

Eucalyptus bark shines when wet. Many species of eucalypt cast their bark in summer and these had only just begun to do so.

The old bark of this tree has been heavily scratched by possums who climb these trees every night. A new skin is long overdue.

While I was out between showers, I checked the leaves of the silk tree for eggs or small caterpillars of Tailed Emperor butterflies. These magnificent butterflies have laid eggs on, and new adults have successfully flown from this tree in most recent years, so I was anxious that any eggs or caterpillars might have been lost in the torrential rain. No sign, but expect updates to the blog when they do appear.

The flowers on the silk tree had only began to open the day before, and in the rain their finery looked rather bedraggled.

Wet pink fur-balls.

Thursday, 13 December 2018

The last frogmouth chicks have fledged

The last broods of tawny frogmouth chicks in my study areas have now fledged. Although there are probably more out there that I don't know about. When there is only one chick, as in the above situation, it is usually the male who keeps close by and protects it.

This single chick was the last from fifty-five territories I monitored this year. Although it has a short tail and wings, it can fly capably between trees and now follow its parents through the wood as they search for food. They will continue to feed the chick for about a month yet as it is not fully developed, only enough to leave the nest site. It is safer for these birds to leave the nest as soon as they can because predators are more likely to find them if they stay in any one place for too long, such as in the nest.

The adult female was up on a branch immediately above them. She is quite unconcerned by my attention because she is familiar with me. Even though I only check on them perhaps four of five times during the breeding season, they are long-lived birds and this bird has seen me often enough over several years to recognise me and know that am not a threat to her or her chick.

In the adjacent territory, another male was sitting close by a single chick. The chick does not know me so it is inquisitive, staring down at the strange human looking up at it, but not alarmed as its father next to it has not given any alarm notice. This chick is about three weeks out of the nest and much larger and further developed than the previous one.

Then a goshawk flew overhead and the local birds gave a chorus of alarm calls. This made the male lift its head and keep alert, although only adopting a partial defensive posture. The chick responded immediately and went a little further into a stick pose. Both birds were wide-eyed and listening to the other birds' messages. Then after a minute or so, the danger had passed and the birds all relaxed.

The female was in a lower branch of the next tree and simply gave me a look as I stood by.

Then she began preening and shaking her feathers, quite at ease in my presence.

The family will move around their territory during the summer and I am less likely to find them again. So this might be my last meeting with her for a while. I left her basking in the sun with her head tilted to catch its rays. They do like to sunbathe.

Saturday, 17 November 2018

Tidbinbilla Moths

Emperor Gum Moth Opodiphthera eucalypti  (c 15 cm wingspan)

I was out at Tidbinbilla Nature Reserve last week helping with a moth survey organised by Glenn Cocking and Suzi Bond for their book on moths of the Australian Capital Territory. The site was well sheltered beneath tall eucalypt trees and I managed to photograph about a dozen species. Here is a small selection of the ones I photographed. It is the colours and form that appeal to me. Knowledge of these species is so sparse that I cannot fill out the text to tell more about them, especially their lifestyles, habitats and foodplants. Hopefully that will all be in the book.

Melanodes anthracitaria dark phase (c 5 cm wingspan)

This rather ordinary moth is worth a mention because it occurs in two colour forms; a dark all grey phase, and light phase of grey blotched with creamy/yellow.

Melanodes anthracitaria light phase

Hypobapta sp. from above (c 4 cm wingspan)

I like to see the moths' tiny faces, antennae and those big round eyes. 

Hypobapta sp. from the side/front

Praxis porphyretica (c 4 cm wingspan)

Callitera rotundrata (c 4 cm wingspan)

Cleora sp.  (c 4 cm wingspan)

What wonderful antennae.

Nisista sp. (c 4 cm wingspan)

This species looks so much like a rolled-edged leaf lying on the forest litter.

Endotricha ignealis (c 2 cm wingspan)

This species seems deliberately to hold its forequarters up on its long legs, and its great long antennae are swept over its back. 

Endotricha ignealis 

Parepisparis lutosaria (c 7 cm wingspan)

Finally, this was my favourite find of the night, magnificent colour and form.

Saturday, 10 November 2018

Small Ant-blue

Acrodipsas myrmecophila

Small Ant-blue butterflies are indeed small.

Although when they fly in swarms like this one, in which there were of over a hundred individual males, they are spectacular.

This is the tree they were flying around, a small Blakeley's Red Gum sapling, with some dead wood lying around, in an open grassy woodland on the edge of the suburbs. The butterfly is a rare resident in the Canberra area, and is uncommon or very localised throughout its range from Victoria to southern Queensland.

Here a group of four adults (all male) have newly emerged from the ant nest they have developed within and overwintered as larvae. The ants are Coconut Ants Papyrius nitidus, and the butterfly larvae feed on their larvae. The ants build their nests in dead wood lying on the ground and in the base of the saplings.

Once their wings are fully extended they begin flying around the nest trees and perch on the branches and leaves, ever watching or smelling for females.

When fresh, their wings have a delicate fringe of scales.

When a few days old, the fringes are tattered and the wings themselves become chipped and ragged. The metallic blue of the bronze upperwing shows in this photo.

Two males perched on my watch as I was photographing the flock. They seldom sit with their wings open for more than a few seconds.

The females were scarcer and seemed to mate as soon as they could fly. The next time they became obvious was when they were seeking a crevice or shady piece of bark at the lower parts of a sapling to lay their eggs in.

I never saw a female sit with her wings open and this one only shows a glimpse of the bright metallic blue of her upperwing.

Once they have laid their eggs the females die. Or in this case are immediately killed and dismembered by the ants. How did the ants know to let her lay her eggs before attacking her. They were in attendance all the time she was laying. The blue of her wings is more easily seen now.

The males probably live for a week of so, competing to mate with a female, but they too can become prey. This one flew into a spider's web, she can be seen top right. Other males were caught by birds, such as Noisy Miners which had a nest in the ant-tree.

The whole flying season probably only lasts for a one or two weeks. Then once the adults have died, the species continues as several instar stages within the ant nest until the next generation emerges the following year. But what do the ants gain from the partnership? or are they simply conned by some pheromone emitted by the butterflies and larvae?

Wednesday, 31 October 2018

First Frogmouths fledging now

An adult male Tawny Frogmouth sits with one of his chicks in the nest, while the sibling sits out along the nest branch.

This one would likely have been flying about between the branches, if not neighbouring trees, over the past few nights, then returning to the nest by dawn. Perhaps, the sooner they can leave the nest at night the safer they are from predators, by separating from the group. The chicks do make a rasping, coughing call when they are being fed, and that could attract owls, for example.

When viewed from the other side, it seems like both chicks are actually out of the nest and on the branch rather than in the nest, which is just the cradle of twigs in the fork. That is all frogmouths need for a nest, enough to hold the eggs, any more twigs and the nest would be bulky and so betray the birds presence. A little is better for these birds, who rely on their camouflage for concealment.

This chick doesn't look much younger, only a day or so in difference. These shots were taken yesterday, so I am sure both chicks will have fledged by tonight, although they might still return to their nest for perhaps one more night. As it's Halloween tonight, watch out for some of these spectres flying between the trees, silently gathering moths. There is nothing frightening in nature, just fascinating.