Sunday 14 September 2014

Cockatoo Sunset



I was out yesterday sunset watching the sun go down over the Brindabellas, our local hill range, when I saw this pair of Sulphur-crested Cockatoos Cacatua galerita come in to display and call in an old dead tree. Dusk is a wonderful time of day, with so much wildlife activity going on. And these birds certainly drew one's attention with their raucous calls - they don't sing too well.




They looked so splendid with their crests erect against the pink sky - terrific birds. I like them despite their reputation for wanton vandalism and noisy neighbourly behaviour.




And now, if you have a song in your head click here and sing along ........

Friday 5 September 2014

Echidna

Echidna spines - quills - there is a layer of soft fur between the quills for insulation
The warming weather has brought out all sorts of animals and this echidna was busy grubbing for food yesterday. She was a big one, about 4-5 kilos and probably hungry after the lean months in the cold Canberra winter when she would likely have spent much of the time in torpor hidden in a burrow. I found her by following up the alarm calls from an Eastern Rosella and a mob of Noisy Miners, not that she was a threat to them.

She was slowly working her through the undergrowth
I could see that she was busy with her head down and a she was walking in my direction I knelt down to lean the camera on a fallen branch, then watched as she came closer and closer, to a few metres away, still quite undisturbed by my presence.

Echidnas spend spend much of their time tearing open old fallen branches in search of termites
It was such a treat to be able to watch this echidna from front on, so often they see or hear us first and either scuttle away offering a rear-view, or they quickly dig themselves down into the ground, curl up and hide. I could see just how powerful those limbs are as she dug around. The limbs are shortened for more strength and the bones in the feet are fused into tight pads. Only the extreme digital bones protrude and they are sheathed in thick claws - pretty tough finger nails.

The thick strong claws and highly adapted snout
Their eyesight is not poor, but not much more than adequate for detecting potential predators or recognising their way around their home range. They do have a wonderful nose though, with finely tuned touch, smell and electrical receptors. The whole modified mouth parts including the nose are covered in a leathery skin and I watched as she poked this snout into the soil, surprisingly firmly for such a delicate organ. Every now and then i caught a glimpse of her long sticky tongue which whipped in and out to catch termites or any other insect which I could not see as they were all out of view down in the holes.

The hind claws point backwards with long curling outer claws.
These are used for grooming between those long quills
With so many quills and as they use the evasive action of curling into a ball for protection, any large external ears structure would be a disadvantage. So echidnas have simple ear-holes hidden within the fur and quills. I had good views of these as this one stretched and bent at my feet. They hear most people approach, as people are generally noisy, and they go quiet and still til the threat passes. Yet, I can recognise the distinctive shuffling sounds which echidnas make, and I turn the tables to stop still and watch them. That is usually from a distance, though, not as close as with this one.

The echidna's ear is hidden below  the quills
After about twenty minutes of undisturbed behaviour watching, I shuffled off myself. The echidna stopped still as I stood up, but I was gone before she felt any need to dig for safety. She then walked off unconcerned.

 An undisturbed echidna carries on with its own business

Tuesday 2 September 2014

A Bzzzy Spring day

Apricot blossom in full flower
Today is the the first calendar day of Spring and Canberra is full of blossom-bearing trees; almond, cherry, plum and apricot. These images are of apricot blossom in our orchard and while I was taking a few photographs of the spectacle I thought I would try to capture some shots of the honey bees that were busy collecting their nectar.

The flowers have a cluster of stamens and a single style with a stigma at the tip. One can be clearly distinguished
 in the right-hand flower as a grey stem with a simple round stigma at the tip, compared
 with the white stems and double head on the anthers,
Honey bees are feral animals in Australia and can cause harm to native species by such action as taking over tree cavities which denies other animals shelter and nest sites. However, they are here and are considered economically important for their pollination of flowers which leads to fruit, nut and seed production. Last year, our blossom flowered during a cold period and there were very few bees or other insects flying. The result was very few fruits on our trees. This year, the blossom is out during a warm sunny spell and insect life is busy around the trees, but mostly honey bees and a few hoverflies.

A honey bee approaches a cluster of apricot flowers
I was using a 60mm macro lens on my camera for the blossom shots and when I turned this towards the bees in flight I met a considerable challenge to freeze them in flight. Most of these shots were taken at about 1/8000th of a second at F9. This was fast enough to grab detail in the insects' body, but not enough to freeze their wings. Honey bees only travel at about 15 miles per hour, but when close up, only centimetres away, they are in and out of frame in no time at all. To catch a bee in frame was difficult, to catch one in focus more so. I took over three hundred shots and only came a away with about twenty good ones. My camera was a Nikon D700 set at 4000 iso, on high speed continuous shooting, and the battery ran down pretty quickly. I don't use flash for wildlife shots.

This bee's hind legs hang low under the weight of nectar stored in her nectar pouches.
Honey bees flap their wings at 240 beats per second and twist /rotate them for directional control.

They really are very maneuverable; hovering, flitting and zooming about from one flower to the next
I sat at the base of a tree and waited for the bees to come within range as any sudden movement would alarm them and they would fly off to the far side of the tree, or another tree nearby. Once I had determined what film speed to use, all I needed was patience, and quick reflexes when one did come into frame. But just sitting amongst the blossom was an experience itself as the scent was amazing. I wonder how its smells to a bee.

The blossom is well adapted for pollination by hairy-bodied bees.
Once they bees landed on a flower they had to clamber through the tangle of stamens to reach deep into the heart of the flower where the nectar is stored in a receptacle around the base of the style. In doing so, they become covered in pollen and when they fly to another flower they offload pollen onto that plant's stigma, and pollination ensues.

The bees have to reach deep into the flower to reach the nectar.
I could see what was happening at the time, but it was only when I downloaded and catalogued the images that I could see and appreciate the detail of such everyday animal behaviour.

And when they leave the flower, their face, eyes, legs and body are all coated with sticky pollen.

Saturday 30 August 2014

Sign of Spring

A male Shingleback follows a female - slowly

Yesterday I came across this pair of Shinglebacks Tiliqua rugosa in the local bush. They are considered to pair, as they remain in the same partnership for years. They can live for over ten years and they probably share overlapping home ranges, which in turn probably leads them to more likely mate together in spring, rather than with individuals from farther afield. I have only ever seen them this close together in spring when they are about to mate. So, are they a pair or simply in a loose partnership.

The female was longer, and had a fatter tail - probably important for her to be in good breeding condition

The male was creeping along behind the female, following her scent, which contains pheromones, signalling that she will soon be ready to mate. The male would want to be close by all that time to ensure that he is there when she is ready and to ward off any intruding males in the meantime.

The male was following in her tracks, tracing her scent trail

Most skinks are quick to run off as soon as approached and we seldom have time for a decent look at them. Shinglebacks however remain still and rely on that to conceal them - they just look like sticks lying in the shadows, and they are usually under grasses or shrubs.

The scales or scutes of a reptile's skin are perfectly arranged with exquisite detail around the mouth, nose and eyes

I took these photographs from less than two metres, more than close enough to capture the detail of their scale patterns without making them feel insecure and want to run (shuffle) off as a last minute defense.

Shinglebacks are quiet and unobtrusive, they allow  close approach, but I never pick them up - that would be obtrusive

Monday 25 August 2014

Footprints in the snow

A snow-covered track through the forest
It is now Spring down on the plains and winter seems long ago. Yet it was only a week or so since I was up monitoring Superb Lyrebirds on the high slopes of the Brindabella range west of Canberra, and it was snowing. Fresh snow always adds another dimension to a day out and also a quick and easy method of determining what animals are about as any that walk must leave prints behind.

Lyrebird footprints on the left, fox on the right
Unfortunately the first species I found tracks of was Red Fox, an introduced pest species. I am familiar with these from years spent in Scotland where I have seen countless such tracks while exploring the Highlands in winter. Fox prints are easily recognised by the straight line followed, often along a track as with most predators which patrol large areas in search of prey. They like us, probably use these routes for quick direct access to and from their dens. Local foxes would be familiar with all such features in their territories. The prints are small prints, with four pointed toes tightly set and the hind paws fall neatly into the mark of the front paws, leaving only a single set of paw marks per stride.

Fox prints fall on top of one another when trotting like this one was
There were a few prints from unidentifiable small birds, but none from any other mammals or marsupials. The next obvious trail I found was of a lyrebird. Again, set in a straight line as it had walked along the road, but not for far. The fox had walked for over a kilometre along the path, the lyrebird only for several metres as it had stepped out of the thick scrub on one side of the track, along the line, then down into the scrub on the other side.

Lyrebirds take long strides when walking quickly
The lyrebird's stride was short initially as it left the cover, it lengthened as it entered open ground, then its steps shortened as it pecked for food on the edge before disappearing into thick cover again. As a bird of dense forest it would likely feel exposed and vulnerable to predators while in the open, so was likely in a hurry to regain shelter from the thick scrub.

Prints tell more than just who made them.

The distinctive outline of a lyrebird footprint - three long toes forward, one backward