Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis
Showing posts with label Flight. Show all posts
Showing posts with label Flight. Show all posts

Tuesday, March 09, 2010

Swifts zoom past Robertson

I know, I know, I know - Spine-tailed Swifts (as I grew up calling them) are now officially called "White-throated Needletails" (Hirundapus caudacutus). But that is a terribly clunky name, for which we owe a debt of gratitude to the "taxonomists" who set the international rules of nomenclature for all living creatures - birds, animals, plants, fungi and all the other creatures which swarm on the face of the earth, and especially within its bowels.

In this case, the rules are simple, we fit in with the names used in other countries where our birds are also found. If they had a name for a bird we subsequently found and named here, then that first name rules. That's roughly how it works, anyway.

Our explorers were a slack lot, and didn't "find" Australia until 1770 (well, officially, any way), and by then Asia was well and truly on the way to being exploited by Europeans. So in the world of taxonomy, their (European) names win out. Not the names the Japanese or the Indonesians use (of course) that would be too simple by half. No, I mean the names which the German, Dutch, French and English scientists gave to these Asian birds, back home in their dusty museums.

Hence "White-throated Needletail". You can see this particular feature of this bird, in a rare image of a dead specimen of this species, which happened to be found dead in Canberra. But, looking at that photo, you have to ask - who else but a Museum worker would suggest this obscure and nearly invisible feature of a bird be used to signify the generic name of this remarkable, fast-flying bird?
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Why am I writing about Needletails? Well today I managed to take a few snaps of several birds as they flew fast and low past my place, this afternoon. This is the first occasion I have managed any sort of photograph of White-throated Needletails.

Only once before have I ever photographed Swifts, and those were the even rarer Forked-tailed Swifts. But they were very co-operative, and a large flock circled around my house for about 15 minutes, and then disappeared. A first and only visit.

I had seen several Needletails two weeks previously, but I did not manage a photo on that occasion. This is only the second sighting of this species for me, this summer.

"Swift" sightings are always exhilarating, as the birds fly so fast, and zoom past you in such haste that you have to swerve your head to follow their movements.
And it is all the more remarkable when you realise that they are not just flying, they are feeding on the wing - catching insects as they go.
How remarkable must their eyesight be - to see an insect, when travelling in excess of 100 Km/hr., and then steer towards that insect, open one's beak and catch that flying insect?Every now and then one gets lucky enough to say - that shot is as good as I can hope to get tonight - with this light, and this lens. Thank you and good night!
And as my Brother Brendan has just pointed out to me, this photo is worth showing - if only for contrast in wing shape and performance. As we were sitting on the back deck, watching the Needletails zip past, a small flock of Black Cockatoos flew past. Here they are.

Check out the remarkably different wing shapes and wing flap styles and of course, the very long tails on the Cockies.
Those wing shapes and the tails, contrast against those of the Needletails whose tails have been reduced to mere stumps with fine needles in them (which they apparently use for perching on rocky cliff faces) - when nesting in Korea and Mongolia.

In aeroplane parlance, the Needletails are obviously the F-111 (with adjustable wing angles) and the Cockies are World War 2 Lancaster Bombers. Both can fly - but they do so in a very different manner.

Sunday, July 05, 2009

Wedgie at the Flinders Ranges

Every now and then a friend shows you some photos you wish you had taken.

I have never been to the Flinders Ranges, in South Australia, but my friends Phillip and Cathie Owen have been. Last Wednesday, at the CTC Choir practice, Cathie showed me some photos - and this series just stood out as worthy of publishing.

So, here they are.

Wedge-tailed Eagle (Aquila audax) on ground, near a dead Kangaroo.
This bird is probably relatively young, as it shows a lot of red on the neck.
Wedgies get progressively darker as they age.
This bird is nervous, looking around to the right.
It has taken flight.
Note how powerfully it is flapping.
The huge wing feathers are bending under the pressure of the down-stroke.
The wedge-shaped tail is fully spread, to give "lift" as the bird if taking off.
As the bird is clear of the ground, it tilts its right wing down
to begin moving away, under full power.
Quite possibly it would have flown to a safe perching point, within sight of this road kill, so that it could come back after the human intruders had left. For a Wedge-tailed Eagle, A freshly killed Kangaroo is too good an opportunity to pass up.

Thanks to Cathie and Phillip Owen for the use of their photos.

Friday, May 29, 2009

Flight over the Wollondilly and Nattai Rivers

Several days ago I went for a quick flight with my friend Jim.
He wanted to go west, over the Wollondilly River, to show me a particular geographical feature he had seen on a trip back to his home from Cowra.
We flew just south of Bowral - towards Mt Jellore, which is west of Mittagong, and north of the Wombeyan Caves Road (at High Range). Mt Jellore is a near perfect cone which stands high above the horizon in this view (above where I have written its name). (Click to enlarge image)


Unfortunately, the weather was against us, when we got out towards the Wollondilly River, near Bullio. We circled around to see the clifflines and obvious hills out there, but many features could not be seen because of low cloud.
Here is the Wollondilly Valley, with a cliff line from near Mt Wanganderry
which is the highest point on the High Range, along the Wombeyan Caves Road.
Here is Mt Jellore, seen from close above.
This contour map image shows well how round this mountain is.
It is over 800 metres high, rising out of the Nattai Valley and Wollondilly Valley.

The weather was against us, but what could be seen was pretty wild, and invites further examination - by 4 wheel drive vehicle, and on foot.
This remarkable cliff formation is extremely narrow.
Without checking for names on detailed contour maps, I don't know if it has an official name.
I have referred to it as the Knife Edge Cliff, beyond Mt Jellore.
Even Jim was impressed with it, and graciously allowed another fly past, for me to get this shot.
It looks like a natural spot to find Peregrine Falcons, to me.
Wonderful clifflines.