Thursday, 31 July 2008

Black Swans

..... Cygnus atratus

This Australian bird is common and widely distributed in Tasmania. The captain of the Banda, Antonie Caen, is the first European to have recorded seeing them back in 1636. This was at Bernier Island near Shark Bay in Western Australia.

There was once a subspecies which lived in New Zealand but is was hunted to extinction prior to European settlement. Australian Black Swans were introduced there in the 19th century and has since thrived.

Interestingly, Black Swan escapees have been reported breeding in Britain. They are not considered to have established a self sustaining population and so the are not officially recognised as an introduced species there. I recall seeing one on several occasions on the Cromarty Firth in northern Scotland where it made a futile effort to blend in with the local Mute Swans :-)

I was impressed by the 178 Black Swans I counted near Bridgewater the other day and no doubt there were many others I could not see. However, Moulting Lagoon, north-east of Swansea supports a much larger population.

Moulting Lagoon regularly supports approximately 8000 black swans Cygnus atrata and up to 15,000 have been recorded during dry periods. It is the most important feeding and breeding habitat for swans in Tasmania.

Black Swans - Cygnus atratus - Lake Dulverton

Black Swan - Cygnus atratus - Lake Dulverton

Black Swans- Cygnus atratus - Lake Dulverton

Black Swan - Cygnus atratus - Lake Dulverton

  • Management Plan 2003 - Moulting Lagoon Game Reserve RAMSAR Site. - Depar tment of Tour ism, Ar ts and the Environment

Wednesday, 23 July 2008

Caterpillar - White Tussock Moth

Oh ... and you all thought I would do another bird post :-)

I noticed a couple of these caterpillars in the garden today. They are the larvae of the White Tussock moth Acyphas semiochrea. They were well exposed on the outer leaves of a Black Wattle - Acacia decurrens. This wattle is not native to Tasmania and the local foodplant would normally be the Silver Wattle - A. mearnsii. This moth species is not confined to Tasmania. It is found in many areas of Australia and feeds on various Acacia species. The hairs on the caterpillar are also known to cause skin irritations.

The caterpillars feed at night and rest on the foodplant during the day. The two I seen today were so well exposed that I would imagine they stand a good chance of being killed by birds or parasites. If not, then in time they will make a white papery cocoon in which to pupate and will be on the wing from spring through to autumn. You can see the imago by clicking here.

Note: I will probably be out of action for little while. Will be back to blogging soon enough :-)

Acyphas semiochrea
Notice the two forward pointing tufts of hair at the head.

Acyphas semiochrea

Acyphas semiochrea

Tuesday, 22 July 2008

Backyard Birding - 3

I spent about 40 minutes this morning and again a little before sunset watching the birds in the garden. For a while I didn't think any birds were going to show up. After yesterdays weather, with snow down to 200m, they may have all packed their bags and left. Eventually the regulars did make an appearance - New Holland honeyeater, Yellow-throated honeyeater, Grey fantail and Collared sparrowhawk,

A flock of at least 5 Superb Fairywrens were busily foraging on the ground a few metres away and then among the sag and up into a flowering Coast Wattle. The male gave me a chance to improve on the shot I got the other day. It's the only reasonable quality photo for the day.

Superb fairy-wren Malurus cyaneus - Male breeding plumage

I was thinking how I hadn't seen the Yellow-tailed Black cockatoos for some time when not too long after, a flock of at least 6 flew by across the top of the hill. A little too far away for a good photo.

Yellow-tailed black cockatoos - Calyptorhynchus funereus

A immature White-bellied Sea-eagle flew in from the sea. This was my big chance for a good shot but I was too slow and the focus is not too good.

White-bellied Sea-eagle - Haliaeetus leucogaster

The best birds for the day were the pair of Wedge-tailed Eagles way way up the hill. Not a common sight here at all. I'll put this photo in just for a laugh as well as to make the other ones look better.

Wedge-tailed (Splodge) eagle - Aquila audax

Blog Index

I'm experimenting with the idea of creating an index for this blog. One of the things that has put me off blogging in the past is the lack of structure. How do you know what a person has posted in the past without reading every post? I'm hoping this index will alleviate that problem. Of course there is not much in this blog at the moment but better to sort this out now than to wait until it's too big a job.

I've only placed a few entries in the index so far but will work on it later.

I will place a link in the side bar so that this post will always be readily accessible.

Edit: OK I've just discovered that Blogger won't allow me to use Shortcut Anchors so my index layout will not work. It works in preview mode but not in the final version of the post. I've also just realised that their is no reason for the index to be contained within the blog so I have uploaded it elsewhere. Click here for Index

There is still a link in the side bar.

Sunday, 20 July 2008

Masked Lapwing

Masked Lapwing - Vanellus miles

Maybe I should change the header on this blog to say, " emphasis on birds" :-)

While on a shopping trip today we took a quick diversion in search for any easy targets for the new lens. Well aside from Silver Gulls, you don't get much easier than Masked Lapwings. It was actually raining at the time so it was also a good test to see how the lens would go under such conditions.

I don't think anyone in eastern or northern Australia would be unaware of these birds. Their noisy call is often heard both day and night. Just about every playing field, school yard, and air field will have at least one. There are two races of Masked lapwing. Our Tasmanian birds belong to the race novaehollandiae which also occurs through most of south-east Australia.

Their natural habitat was originally grassland and salt marsh and they are rarely far from water. The adoption of the man made habitats of pasture and lawn caused a huge increase in their population through the first half of the 20th century. The presence of humans does not deter them and they will even nest in the most unlikely places such as footpaths. Their nest is just a simple scrape lined with a few bits of straw or twigs. They usually lay 3 or 4 eggs. In 2006 I noticed one pair nesting on a busy roundabout. Unfortunately, the chicks were killed by the traffic but the parents nested again at the same spot. So far as I could tell, this time they succeeded.

Not only do they nest on the ground, they also feed on the ground or on tidal flats. They are surface feeders, primarily taking worms and other invertebrates although they have also been recorded eating seeds and leafy vegetation from time to time.

The breeding season is anytime from June to December. During this time they are seen in pairs or perhaps 3 or 4 birds. However, non-breeding birds in Autumn and winter will gather in large flocks. Recently I noticed a flock along the shore of well over 100 birds. However Michael Sharland in "Birds of Tasmania" talks of flocks of over 1,000.

Another common name for this species is Spur-winged plover. You can see the spur quite clearly on the left hand bird in photo #1.

(Click to see larger versions of the photos)

Masked lapwings - Note the wing spur

Masked lapwing - Stalking

Saturday, 19 July 2008

Backyard Birding - 2

Today I managed a few more bird shots up in the backyard. I'm reasonably happy with the New Holland Honeyeater and the non-breeding male Fairywren. I've also included a House Sparrow for the British readers - a bird which is sadly in decline in the UK while here in Australia it is an unwanted feral. Feral or not they are actually a beautifully marked bird when seen close up.

It seems photographing birds has something in common with fishing as there are always the ones that got away. Today I new there was a bird of prey about as next doors aviary birds and my own ducks and chickens always react to them. I grabbed the camera and took a walk up the back. I waited for 10 minutes with not a bird in site. I don't just mean birds of prey, I mean not a bird to be seen or heard. Then just as I turned back toward the house, a Collared Sparrowhawk flew over the neighbour's fence straight toward me, On seeing me it panicked and to an aerial U-turn while I panicked waving the camera all over the place taking shots of trees, bushes, and sky. The interesting thing is that once it had flown off about half a km away, about 15 -20 birds started flitting about all over the place. They must have been laying low until the predator moved on. There was also a pair of White-bellied Sea eagles and a possible Wedge-tailed Eagle flying about the hill but even with the new lens they were too far off to photograph properly.

Click images for a larger version
New Holland honeyeater - Phylidonyris novaehollandiae

Superb fairy-wren - male (non-breeding)- Malurus cyaneus

Superb fairy-wren - male - Malurus cyaneus

Black-headed honeyeater - Melithreptus affinis

House sparrow - Passer domesticus

Friday, 18 July 2008

Backyard Birding -1

I treated myself to a new lens. It's a Canon 400mm f5.6 L. This afternoon the sun made a brief appearance and I finally got a chance to test it. I didn't venture very far - just up the hill in the backyard. The only problem was the birds were keeping their distance but I did manage to snap a few shots. They're not great shots. I'm sure the lens is capable of much better but I find with any new lens it takes a bit of getting used to it's strong points and weak points. The Goshawk was flying through trees as some speed so I'm surprised that I managed to get any shots at all with that one.

Crescent honeyeater Phylidonyris pyrrhoptera

New Holland honeyeater Phylidonyris novaehollandiae

White goshawk Accipiter novaehollandiae

Yellow-throated honeyeater Lichenostomus flavicollis

Thursday, 17 July 2008

Don't Count Your Chickens 'till They're Hatched

..... or your caterpillars

You may remember I posted a series of moth egg photographs. Well one of those photographs was of eggs which I only recently found in the backyard and some have begun to hatch. This poor fellow seems to have died (not unusual) and so it maid a good subject for the microscope. It's not the best picture but keep in mind it is less than 1mm in length. I also ended up with a posterior view so not the most aesthetically pleasing.

The shape of the eggs and the appearance of the caterpillar suggest to me that it may be a Noctuid but this is just a wild guess. The Shape of the eggs is very similar to the Gum leaf skeletoniser - Uraba lugens but they are laid in a different pattern.

My little microscope is not set up for photography. This was taken by hand holding a camera at the eye piece.

Click on it to see a bigger version
This first instar larva is less than 1mm in length.

The eggs were only 0.5mm in diameter

Tuesday, 15 July 2008

Two Ravens

..... or Twa Craws for ony Scots amang us.

Until now I have assumed all four Raven photographs below were of Forest Raven - Corvus tasmanicus. Indeed that is probably still the case. However, I have recently read that the Little Raven - C. mellori also finds it's way to the north coast of Tasmania, albeit rarely. Other than size, which is difficult to estimate from a photograph, most of the features used to differentiate between the two species require having the bird in your hand. The one more visible feature that I'm aware of is the Little Raven is said to have more prominent throat hackles while the Forest Raven's throat hackles are said to be inconspicuous.

The first two photos below are of a Cradle Mountain bird which is surely, on location alone, a Forest Raven. Photos #3 and #4 show a second bird at the Duck River in Smithton on the north-west coast. While in all likelihood they are both Forest Ravens, the throat hackles on the Smithton bird are hardly inconspicuous. I've only been back in Australia for a relatively short time so if any experienced birders out there wish to opine on the matter, I would be grateful. I suspect they are both Forest Ravens but I would like to understand what makes them so.

#1 Forest Raven at Cradle Mountain

#2 The same Forest Raven at Cradle Mountain

#3 Raven at Smithton (prominent throat hackles)

#4 Raven at Smithton

Edit: After
Anonymous's comment below, I thought I show details of the eyes.
#5 Cradle Mountain bird on left & Smithton bird on right

Monday, 14 July 2008

Cradle Mountain (Without a Camera)

We enjoyed a trip to Cradle Mountain today. We actually tried to go last week but the road was closed due to snow. Todays weather was much better. There was still a bit of snow on the ground from last week but the roads were totally clear. The mountain itself was magnificent with a good covering of snow, brilliant white in the sunshine. You may like to see a photo but.... guess what? I left my camera at home. Have you ever noticed that there is a direct relationship between the distance from your camera and your chances of seeing something interesting. Today we seen at close hand Red-necked wallabies and a wombat just a few metres away. The others seen a possum sticking it's head out of a hole in an old myrtle tree. Aside from the usual friendly Black Currawongs, there was also a flock of Green Rosellas and Yellow throated honeyeater flitting about, landing just in front of me and actually begging me to take a photo. Oh well - there's always next time :-) At least I scored some good memories and a copy of the book "Fungi Down Under" from the park shop.

For now I'll just have to show a couple of photos I took last October.

Cradle Mountain a a cloudier day last October.

Black Currawong at Dove Lake (Cradle Mountain) last October

Tasmanian Native Hen at Dove Lake (Cradle Mountain) last October

Sunday, 13 July 2008

Mycological Perambulations

..... or traipsing around looking for fungi

This afternoon we took the opportunity to go searching for fungi. Our expedition headed of to Fern Glade along the Emu River. The slopes of this river valley are host to wet Eucalyptus forest with White gum (E. viminalis) and Stringybark (E. obliqua). There are also pockets containing many rainforest species. The path along the river in the main recreation area has an abundance of large tree ferns.

Aside from walking and BBQ's, many people come here hoping to spot a platypus or to check out the bird life. However, Fern Glade is also a great place for fungi. My knowledge of fungi is sorely lacking so for now, I have not attempted to identify the species shown below. I post them here simply to share their beauty. For the record, my own favourite here is #10.

Don't forget you can click on the images to see the larger version

#1 # 2

#3 #4 # 5

#6 #7 # 8

#9 # 10

#11 # 12

#13 # 14

Edit: Despite what I said above, I couldn't resist trying at a few ID's. Here's what I've come up with so far.

1: Clitocybe clitocyboides
3: Stereum ostrea
4: Stereum ostrea
6: Leotia lubrica
7: Leotia lubrica
8: Clavaria amoena
10: Pseudohydnum gelatinosum
11: Ramaria sp
12: Ramaria sp
14: Geastrum sp

Saturday, 12 July 2008

Shy Albatross

I had terrific views of an albatross from my backyard today. It was a Shy Albatross, Thalassarche cauta. The rough seas and onshore winds brought it very close into shore - no further than 50 m at times. I watched it for around 10 - 15 minutes as it flew back an forth and between the waves, it's wings often almost touching the water.

The hill at the backyard allows for views over the house, across the road, and out to sea. In the past we have seen large pods of Bottle-nosed dolphins and Humpback Whales from the yard. While not the best seawatching vantage point, it's certainly a most convenient one and I shall have to pay more attention in future to what passes by.

While I wish I had a lens capable of capturing the moment, for now at least that is not to be. Alas, the following photo is not my own.

Photo used under Creative Commons license © aaardvaark

Mothing - 10th July 2008

Not many moths of late as it has been rather cold and wet. Here's one from the 10th which I did not post. I have not had a chance to try to ID it. For now I will simply say it appears to be a Noctuid.

In the last shot the moth almost looks two-headed. Perhaps this is some kind of automimicry defense mechanism.

Edit: This moth turned out to be Pantydia diemeni

Dorsal view - FW18mm

Frontal view - Prominent dark mark above head

Lateral view - Wings not at rest. Antennae held under wings.