Author Archives: Patrick Kavanagh

The bush awakens

It’s wonderful to wander through our bush full of flowering Golden Wattle (Acacia pycnantha). As the colour fills the woodlands, invertebrates seem to be waking up.

Golden Wattle

Golden Wattle blossom

The flowers attract many pollinators and in the sunlight of a still clear day, minuscule flies are common. Some of this seem well under a millimetre long, but I’ve yet to manage a photo of one so small. This one was about 3 mm long.

fly on golden wattle

Fly on Golden Wattle

Ants on the wattles seem more interested in the secretions from the little gland in the bend of the leaf petiole than they are in the flowers. This one was only couple of millimetres long.

Ant on Golden Wattle

Ant at leaf petiole gland

Looping caterpillars like this one of the moth genus Chlenias are out in force. This one is hanging from a Golden Wattle.

Hanging Chlenias - Looping Caterpillar

Chlenias caterpillar

Others were munching on leaves and flowers.

Looping Caterpillar - Chlenias sp.

Chlenias sp.

These same caterpillars are also very keen on the Drooping Cassinia (Cassinia arcuata).

Chlenias sp

Chlenias sp. on Cassinia

The Cassinia is also favoured by small flies at the moment.

Fly on Cassinia

Fly on Cassinia

Nearby, a Climbing Sundew (Drosera macrantha) seemed keen on the small flies that were visiting the Cassinia shrubs. Can a plant be keen on something? I was very excited to find this plant as I’ve not seen this species of Sundew on our place in the 25 years that we’ve called it “our place”. Thanks to Frances Cincotta for identifying the plant for us!

Climbing Sundew

A Climbing Sundew feast.

 

More winter macros

As the Golden Wattles (Acacia pycnantha) bloom, a wander into the bush reveals some more of the invertebrates that brave the winter cold.

On one of the beautiful wattle blossoms, a tiny fly, 5mm long, sleeps deeply as I twist the branch to get a clear view. Pollen has stuck to the tiny sleeper.

Fly on Golden Wattle bloom

A fly sleeps on Golden Wattle.

On another Golden Wattle, a Slender Leaf-shaped Orb Weaver spider (Araneus talipedatus) sits in his beautiful web. As my light disturbs him, he runs up the web to shelter on a leaf. The big, brownish pedipalps give away the sex of this tiny predator.

Slender Leaf-shaped Orb Weaver

Slender Leaf-shaped Orb Weaver

A small bright red spot on an old stump catches my eye. I am delighted to find a Red Velvet Mite hunting on the stump. This adult, about 5mm long, freely wanders for food in leaf litter and on dead wood. Its larvae attach to insects and spiders, drawing blood before dropping off to metamorphose into this delightfully fuzzy little creature. These small animals are classed as arachnids, but are not spiders.

Red Velvet Mite

Red Velvet Mite

I was very pleased to be able to see the eyes on this wonderful creature. The photo looks to me a bit like a mini red echidna.

Red Velvet Mite

The face of a Velvet Mite

Red Velvet Mite

Quite an agile explorer

 

Winter’s tiny predators also undaunted!

A week or so ago, I posted about the tiny ants foraging on a winter’s night. But I’ve also been collecting photos of some of the tiny predators also.

Warning for arachnophobes – these are mostly spiders!

Most of the spiders I find in the bush at our place at Strangways at this time of year range from very small to miniscule. Most of the shrubs in our understorey have a number of tiny spiders hanging from webs, which can be incredibly challenging to photograph. This little one was no more than 2mm long. I like the way some of the eyes peep out in this one.

tiny spider

A miniscule spider

Slightly larger, about 5mm long, was a little orb weaver with a beautiful web draped over a gap in the bark of a Long-leafed Box.

Orb weaver

Orb weaver

Spiders of the genus Araneus are also orb weavers. I think this species is Araneus talipedatus – Slender Leaf-shaped Orb Weaver. I think the large palps on this specimen mean that it’s a male. According to the CSIRO “A Field Guide to the Spiders of Australia” this genus usually hunts by night using their orb webs.

Araneus sp? male

Male Araneus

Another specimen had small palps, perhaps a female.

Araneus sp?

Female Araneus

Dangling by single thread from the branch of a Golden Wattle was a small grey spider about 6mm long. When my light and camera got too close, it scuttled quickly up the thread to the branch. At that point I could see from its two large eyes in the middle of the front row it was a Jumping Spider. I was a bit surprised as I’d thought that Jumping Spiders were mainly daytime hunters, leaping to catch their prey. I didn’t know that they like to hang from threads at times. The people at the Australian Spider Identification Facebook page identified this one for me.

Jumping Spider - Cytaea sp

Jumping Spider – Cytaea severa

Jumping Spider - Cytaea sp

Good camouflage!

The only larger spider that I’ve seen on recent nights was this impressive Eriophora biapicata. This one was about 20mm long.

Eriophora biapicata

Eriophora biapicata

But of course, not all winter predators are spiders. Some are not even animals! It is a spectacular time of year for Scented Sundews, Drosera whittakeri. In places the 25mm diameter leaf rosettes carpet the floor of our bush, supplementing their diets by attracting, poisoning and digesting small invertebrates with the sticky secretions on their stalked leaf glands.

Scented Sundew (Drosera whittakeri)

Scented Sundew

At 3:1 macro (ie the image projected onto the camera’s chip is 3x life size) these sticky glands have an extraordinary other-worldly appearance.

Scented Sundew (Drosera whittakeri)

Scented Sundew leaf glands up close.

Undaunted by winter’s cold

The middle of winter is not a great time for invertebrate macrophotography. Dependent on the environment for body heat regulation, these tiny animals are mostly in some form of dormancy. But not all, and I am amazed at how many very tiny spiders, flies and ants seem to navigate the frosty conditions of a Newstead winter.

Last night, I was impressed to find a number of small ants seeking out food on the wattles at our place at Strangways. One species were small black ants, about 5mm long. I think they are a species of the genus Notoncus, but I’m very happy to be corrected. When I got to look at this photo on my computer, I was amazed to see what looks like a tiny brown mite on the ant’s abdomen. I find the size of some of these mites mind bogglingly small.

Notoncus sp.

Notoncus worker on Golden Wattle, with mite

As is often the case, these ladies were feeding from the little gland in the bend of the wattle leaf stem.

Notoncus sp

Feeding at Golden Wattle gland.

Another species of the same genus is one that I often see at night – Notoncus hickmani (I’m more confident about this as the friendly people at bowerbird.org.au identified it for me last year). Having done a bit of research on the web about this genus, I have found out that not much is known about their biology. These workers also look about 5mm long to me.

Notoncus hickmani

Notoncus hickmani on Silver Wattle #1

Notoncus hickmani

N. hickmani #2

About twice the size of the Notoncus ants was another species, black and quite graceful with ornate looking spines at the back of the thorax. I think this ant is a Campomyrma species. This is a sub-genus of Polyrhachis. Again, I’d like to be able to say something useful or interesting about these ants, but there seems very little information about them on the web. Given that all these ants are pretty common, it says a lot about what we don’t know about these incredibly important insects.

Polyrhachis-Campomyrma_19-07-16_3

Campomyrma sp?

 

 

 

Macrophotography and invertebrates at Castlemaine Field Naturalists

Praying Mantis nymph

Praying Mantis

I am very excited to have been asked to do a presentation on macrophotography and invertebrates for the Castlemaine Field Naturalists Club this Friday, July 12th. I’ll be talking about the challenges of photographing small inverterbrates in our bush and about some of the things I’ve discovered about our local insects and arachnids through taking photos of them.

The meeting starts at 7.30pm at the Uniting Church hall in Lyttleton St, Castlemaine.

Myrmecia pyriformis

Myrmecia pyriformis

Just down the driveway, it’s crane and giant emu time

A clear winter night is a delight for southern hemisphere astronomers as the centre of the Milky Way galaxy is in a perfect position for observing. As I was spending some time at my telescope eyepiece a couple of nights ago, I couldn’t resist getting the camera to capture the spectacle of the galactic centre rising over our driveway. Just down the road really!

The centre of the galaxy rises over Strangways

The Galaxy rises!

The centre of the Milky Way is in the direction of the Arabic-European constellation Sagittarius – the centaur archer. While the bright stars of Sagittarius are all less than 100 light years away, the supermassive black hole at the centre of the galaxy is 25,640 light years from us and the galaxy itself is estimated to be 150,000 light years across. A light year is the distance light travels in a year – about 10,000,000,000,000 kilometres.

Also in this photo are the constellations Scorpius and Grus – the scorpion and the crane. Both of these constellations actually look like the beings the are named after, but the upswept wings of the crane are actually out of the frame at the bottom of the photo.

Gas giant planets Jupiter and Saturn can also be seen in this photo – about 50 and 80 light minutes from us, so very much closer to home.

The dark patches across the Milky Way are lanes of cold gas and dust, from which new stars will one day be born. At the top right hand corner of the frame, between two stars of the Southern Cross (Crux) is a dark gas cloud unpoetically called the Coal Sack by western astronomers. To indigenous Australian astronomers, this was the head of the giant emu, the shape made by the dark clouds along the Milky Way.

The centre of the galaxy rises over Strangways labeled

Many years ago, Newstead Landcare were fortunate to have a night under the stars with John Morieson who had studied the records of the astronomy of the Boorong people of Lake Tyrell in northern Victoria. They called the giant Emu Tchingal and it was a giant who ate people – perhaps the giant carnivorous megafauna emu that once roamed Australia. John told us of the fight between Tchingal and Bunya, the Ring-tailed Possum ancestor, who drops his spear whilst climbing a tree that we see as the Southern Cross. The spear is seen as the pointers – Alpha and Beta Centauri, whilst Bunya’s head is the top star of the cross (Gamma Crucis), his ears are two small stars above the cross and his tail is an arc of stars to the left of the cross.

bunya labeled

Bunya and his spear and tree

I pointed the camera south to capture more of Tchingal’s head in case I needed to stitch a few photos together to catch the emu’s full glory. As I did so, a bright fireball meteor plunged earthward between the Large and Small Magellanic Clouds. These neighbouring dwarf galaxies are 150,000 and 200,000 light years away respectively and consist of 15 billion and 5 billion suns. The Milky Way is 200 billion suns in mass.

Fireball between Magellanic Clouds

A meteor passes between the Magellanic Clouds

Fireball between Magellanic Clouds labeled

To the right of the Southern Cross along the Milky Way is a small bright patch around a small yellowish star, Eta Carinae. It is the seventh brightest star in the constellation Carina, the keel of Jason’s ship Argo. This star is likely to be the largest star in the Milky Way, 150 times the mass of our sun and is 7500 light years away. The fuzzy glow around it is a vast cloud of dust and gas, lit by Eta Carinae and forming numerous clusters of new stars. Eta Carina is very unstable and underwent several convulsions in the 19th century, throwing off clouds of material that are easily seen through amateur telescopes.

Incomprehensible as Eta Carinae may be, the Tarantula Nebula in the Large Magellanic Cloud manages to dwarf it. To the right of the north end of the Cloud’s bar, it appears as a faint, fuzzy round glow to the naked eye under a dark sky. It is the largest star forming region in the Local Group of galaxies and have stars up to 300 times the mass of the sun and the nebula is 930 light years across.

Moss, water, wonder.

Moss and a little bit of water go a long way for life and for beauty as well. Frances Cincotta of Newstead’s native plant nursery Newstead Natives recently lent me a tray of germinating seedlings with a thick layer of moss to explore with my macrophotography set-up. The mosses had put up a multitude of spore capsules, which hold water beautifully!

Moss

Moss spore capsule #1

The photo above was taken inside with natural light and the window of the room can be seen reflected in the drop.

At 5x macro, truly each drop holds a world.

Moss

Moss spore capsule #2 at 5x

These images are made by focus stacking. As the depth of the image in focus is very small at high magnifications, one solution is to take several photos at different focal planes and use software to combine the images. This can result in some artefacts, which can be edited out. In this photo, I’ve left the artefacts in to add to the other-worldly feel’.

Moss flowers and dew

Focus stack with artefacts.

A common wisdom in macrophotography of plants is to avoid flash. However, with a tiny subject and large diffuser for the flash, the results can be quite good.

moss 3x stack 3 v crop

Moss spore capsule and water, focus stack with diffused flash.

Moss 3x stack 2 crop a

And again.