Friday, 27 December 2013

Brown Treecreepers: 
How to tell their age and sex

I am building up a portfolio of photographs which show how to age and sex various species of Australian birds. These will be posted in a separate blog, but for now I will upload them to this site and would be grateful for any comments prior to collating them on the new site. The birds have all been caught in mist-nets during long-term field studies, mostly run and organised by Mark Clayton or Richard Allen, to whom I am grateful for their knowledge in confirming the birds' plumage patterns, particularly some of the more tricky species.

As a sample of how I intend to progress with the project, here are a few images to aid people in aging and sexing Brown Treecreepers Climacteris picumnus, following differences in their plumages.

 
Adult (1+) male Brown Treecreeper
04/11/2012, West Wyalong, NSW.
The bird on the left is an adult male, categorised  as 1+, a bird of one or more years old. It is recognisable as an adult by the bold eyestripe and breast markings. The sex is determined by the black freckle spots arranged in a necklace around its throat. The throat's rich buff-orangy colouring is also indicative of age, although more comparative and less useful as a guide if only one bird is seen at a time.

The dark dashes on the breast feathers are the brown edges to the breast feathers which have a wider band of white/buff down the shaft than in those of birds in their first year. Therefore the dashes on the adult birds are farther apart.









First-year (1, juvenile) male Brown Treecreeper
15/12/2013, West Wyalong, NSW.
The bird on the right is a first-year male,
categorised as a 1 juvenile, as it still has folds of skin around the base of its bill, the remains of its juvenile gape.

Again, it has a black necklace of spots. Females, adult and juveniles/first-year birds, have rusty-red spots on their necklace.

First-year birds of both sexes have narrower dark-fleck patterns on their breast feathers. This being due to narrower bands of white along the feather shafts than on adult birds.













The same adult male
When the adult's head is seen from the side, there is a distinct contrast between the prominent eyestripe and buff supercilium, highlighted by a faint white top edge. These markings on the first-year bird are less obvious, as is the contrast between the grey tail tips and the rest of the tail, which in the adult is strong due to the darker upper tail colour. There is a similar difference between the dark primaries and primary coverts of the adult and the grey/brown colour of those of the first-year bird. 

When seen close in the hand, the tips of the adult bird's greater coverts are faded and frayed, while those of the first-year bird are fresh with buff tips. This last point is also a useful diagnostic feature for aging birds of many other species and will be repeated when applicable in further aging and sexing of birds notes as I compile them.

The same  first-year, juvenile.

Monday, 23 December 2013

Yet another Golden Eagle found poisoned on a Scottish grouse moor

A satellite-tagged Golden Eagle lies dead, poisoned on a grouse moor (RSPB Investigations)
Despite assurances from the authorities that the killing of Golden Eagles and other raptors in Scotland is being dealt with, yet another eagle has been found poisoned on an estate managed for grouse shooting. And once again it is in the Angus hills where many other birds have been found killed in recent years.

This bird was satellite-tagged while a fledgling in 2011 in Perthshire, from where it moved to Badenoch and lived freely. However it fatally moved to Angus and died from ingesting poison, probably by eating laced bait deliberately laid out to kill raptors. Roy Dennis of Highland Foundation for Wildlife, who was tracking the bird became aware that the bird had not moved for several days, so alerted the RSPB, whose investigation officers and police found the bird dead at the spot marked by the satellite tag's coordinates. Subsequent analysis showed that the bird had died of poisoning by carbofuran. The bird's movements throughout its short life can be viewed by clicking the link below to the HF for W website.

http://www.roydennis.org/category/golden-eagle/fearnan/


Will this killing ever be stopped? (RSPB Investigations)

The movement of this bird clearly shows how if such a bird is killed on any estate it is not only the local birds which are killed but those from the national population. As the birds are killed, they leave a gap in the habitat, an empty territory which attracts other birds. These are subsequently killed too and so on. How many of the Scottish Population of Golden Eagles are killed per annum. In the Angus hills alone, in the past five years there have been four other Golden Eagles killed by shooting, poison or trapping, as well as seven Common Buzzards and a Red Kite. And a White-tailed Sea-eagle nest tree was felled. These are only the incidents which have been found and reported, how many more go undetected. Regardless of emotions, this behaviour is illegal and should be dealt with. This is a sad refection on the care Scotland shows for what is regarded by the people as its national bird, surely this time, is THE TIME for the government to be seen to rectify this abuse of our widlife.

I ask all my international as well as Scottish readers to write to the Scottish Minister for Environment and let him know how the lack of prosecutions and effective legislation for the protection of raptors in Scotland looks in the world's eyes. His address is Mr Paul Wheelhouse, Minister for Environment and Climate Change. ministerforenvironment@scotland.gsi.gov.uk

And please forward this page to anyone you know you may be interested.

Thank you.

Fearnan, the eagle which was killed as he was when a nestling (Keith Brockie)

Sunday, 22 December 2013

Probable protective nesting association between Australasian Figbird, Noisy 
Friarbird and Papuan Frogmouth 


A Papuan Frogmouth sits on its nest set between that of  a pair of Australasian Figbirds with begging chicks on the left, and a partially constructed nest of a Noisy Friarbird up to the right.

I have an article on frogmouth nesting behaviour in the recent edition of  Australian Field Ornithology
(Vol 30: pp126-130).

While on a field trip to Cape York in 2011, I found a Papuan Frogmouth Podargus papuensis sitting on its nest about 15m up a Leichhardt Pine Neolamarckia cadamba by a roadside on the edge of rainforest. The nest was well concealed among epiphytic ferns on one of the lower limbs, and although there have not been many nests of this species described, from experience with the closely related Tawny Frogmouth, I would expect this to be a normal type of nest site.

However, this nest site was intriguing for another reason. The nest was set within one metre of and between those of a pair Australasian Figbirds Sphecotheres vieilloti and a pair of Noisy Friarbirds Philemon corniculatus. It seems that these two other species had deliberately selected to nest close to the frogmouth nest, probably for protection (the frogmouths had well-grown chicks and would have nested first). The much larger frogmouth would be more likely to ward off any potential predators than the passerines themselves. If this was the case, this would be the first recorded example of a frogmouth or any of the caprimulgiformes behaving as the protective species in a nesting association.


The arrow points to the trio of nests set on
and around the angle of the branch

Thursday, 19 December 2013

Black-eared Cuckoos

A first-year Black-eared Cuckoo on the left, adult on the right
In a recent post I discussed the plumage of a Black-eared Cuckoo Chrysococcyx osculans which we caught at Charcoal Tank Nature Reserve, then last weekend, 14-15 December, we caught the same bird again, along with two younger birds which were definitely in their first year. A useful comparison.

Once again I am grateful to Mark Clayton who organised the trip as part of a long-term study of birds in the area.

The second first-year bird
One of the first-year birds





















The adult bird (right) as described in the earlier post, had a fully marked face and a richly coloured throat and breast.




Both first-year birds had faintly marked faces, with dull throat and breast colouring.














The moult sequence and timing of the various feathers of this species is poorly known, with the information used for the synopsis in the Handbook of Australian, New Zealand & Antarctic Birds being based in parts on only a sample of three birds. And we only have a sample of three. Therefore, I am open to discussion on any points raised.


The two young birds on the left have dull grey-brown rumps and tails; the adult bird on the right has a grey
rump contrasting with a dark tail. The first-year birds have faded feathering overall, while that of the
adult bird is fresh, unfaded and lustrous like other birds of the genus

Although synchronous growth bars on the tail are used as an indication of a bird with its original tail feathers, it seems from comparison between these birds that the adult bird might not really have synchronous bars. Perhaps the feathers can grow and align to seem to be of the same age. The freshness and dark unfaded colouring of the adult bird's tail would seem to be recently grown. Yet, apart from the apparent synchronous tail growth bars, the bird has an otherwise adult plumage. Also, its tail is only slightly worn at the tips, and it has distinct white tips, as mentioned in the previous note, unlike the first-year birds which both have well-worn buff tips. Such bold white tips (compared with buff tips of definite young birds) are often an indication of an adult bird. I suggest that this is indeed a true adult bird which hatched at least two breeding seasons ago, and the first-year birds hatched one breeding season ago.

The first-year birds also had faded, frayed secondary coverts with buff tips, and darker, unfrayed primary coverts
There is another trip to Charcoal tank planned for January, so perhaps if we catch these or any other Black-eared Cuckoos we will be able to note any moult  features which could help to determine this species moult pattern. 

Wednesday, 4 December 2013

Platypus

A typical view of a Platypus on the surface between dives for food
Last week I was out at Tidbinbilla Nature reserve in the ACT, specifically to look for Platypus Ornithorhynchus anatinus and I saw three. The ponds and dams there are probably one of the best places to see these wonderful animals. Although mostly nocturnal, they do come out to feed around midday and if the water is calm and the light flat under an overcast sky they can be spotted paddling around on the surface between dives for prey.

The best way to spot them is to watch for ripples on smooth water
It is always tricky to capture a sharp image of a Platypus as their fur is always slick with water and they glisten in bright light. But it is simply satisfying to sit for a while and watch them as they carry on with their lives, quietly and unobtrusively. A trip out to Tidbinbilla is a true escape from the increasingly bustling city of Canberra.

Platypus are quite common but easily overlooked

Saturday, 30 November 2013

Fan-tailed Cuckoo egg in Scrubwren clutch

A Fan-tailed Cuckoo egg with two of  Large-billed Scrubwren
I was down in the Shoalhaven area a few days ago and while out for a walk through some riverside forest I found a Large-billed Scrubwren Sericornis magnirostris nest. I saw the adult bird flush as I walked by and was surprised to discover that it had built its nest inside an old nest of a Yellow-throated Scrubwren Sericornis citreogularis - on subsequent research I discovered that this is common behaviour of the species. Then when I inspected the eggs there was a cuckoo egg amongst the scrubwren clutch. The egg were likely from a Fan-tailed cuckoo Cacomantis flabelliformis  - as scrubwrens are common hosts of these birds eggs and young, and there were a few of these around the area, but no other cuckoo species.

The cuckoo egg is noticeably larger than those of the scrubwren
There were two scrubwren eggs, but whether there had been three and the cuckoo had taken one out is not known. The cuckoo egg was quite a good mimic of those of the scrubwren, although slightly larger and more spotted overall, and a little lighter in background colour. The scrubwren eggs also had more defined rings of spots around the broad end, especially one of the eggs. There was a faint ring around the cuckoo egg, but not very distinguishable.

The cuckoo egg has a faint ring of spots on the broad end like those of the scrubwren eggs,
but much more general speckling
The nest was a simple relined structure inside the old Yellow-throated nest which looked old as the leaves in the structure were dried and deteriorating. 

The clutch was in an old Yellow-throated Scrubwren nest
The nest was set about head height, c 190cm, and typical of a Yellow-throated Scrubwren in being suspended from a the end of a thin branch over an open patch of forest floor -in this case a footpath, although often they are hung over stream lines.

The nest was suspended over a human track through riverside forest 

Friday, 29 November 2013

Red Bellied Black Snake

Never blinking concentration
While walking with Lachlan through Tidbinbilla Nature reserve in the Australian Capital Territory yesterday, he noticed one, then a second and even a third snake lurking in the undergrowth between the path and the waterside of a small lake. They were all Red-bellied Black Snakes Pseudechis porphyriacus, one of my favourite species of snake in Australia as they have a rich shiny black top side and a fiery red belly - and I have never seen an aggressive one.

A glimpse of the beautiful red belly of the snake as it slipped over a path
The first one glided onto and across the path to drop into a patch of marsh where it carried on hunting for frogs, lizards or whatever else it might eat. The colour on its belly was more easily seen as it crossed the open path than when it slipped through the grasses.

Hunting in the waterside grass
That one was about a metre and a half long and the others about two metres, perhaps one female and two males. But why are people obsessed with the length of snakes, their size does not make them more dangerous (unless they are very large pythons which could kill a human if given a chance). These Black Snakes are very venomous, yet they were quietly getting on with their life and as we left them alone, they left us alone. No one has been recorded as being killed from a bite by any of  this species. 

There was an appropriate visitor sign in the reserve which said 'the only good snake is a live snake' and I for one agree. We just need to be careful if they are around. 

This one would lift its head up to see, or scent for prey, but I don't know why it spread its hood as I didn't approach it.
This is usually a sign to back off, so I did anyway.

Sunday, 24 November 2013

Around Eden

Humpback Whales - mother and calf
Last week I went on a trip down to Eden on the south coast of New South Wales, primarily to go out on a boat trip to see the last of the whale migration pass by, and also to see some local birds of the area - on land as well as at sea. And we had splendid close-up views of two mother and calf pairs of Humpback Whales. They were quietly cruising across the bay outside the fishing port of Eden.

Short-tailed Shearwater - note feet protruding beyond the tail
Although the boat trip was primarily aimed at whale-watching, we saw several species of seabirds including the most numerous -Short-tailed Shearwater Puffinus tenuirostris. While the whales were on their way south to the Antarctic for the southern summer, these birds were on their way back to their nesting burrows on offshore islands around Australia, having just returned from as far as the Bering Straight where they spend their non-breeding season.

A few shearwaters landed behind the boat in anticipation of bait being thrown out - as done on some birdwatching trips
I will post more detailed accounts of birds seen on the trip later, but for now I draw attention to what for me was the bird of the trip - the Southern Emu-wren Stipiturus malachurus. I like these birds because of their tiny size, generic wispy tail and overall adaptation to life in grassy heaths. They can be difficult to find in amongst the grasses, but it is well worth listening out for their thin trilling calls. A seemingly simple, yet marvelous bird.
  
The distinctive silhouette of an Emu-wren
Both form and colour are unique, as is their character.

An adult male Southern Emu-wren in full colour - a rather smart bird

Friday, 22 November 2013

Black-eared Cuckoo

It has been a rather hectic past few weeks, what with the Tawny Frogmouths fledging and doing a bit of general bird-watching around the south east of New South Wales and the ACT. I'll post as much as possible over the next few weeks, but meanwhile here are some shots of a Black-eared Cuckoo Chalcites osculans, which was caught during a regular study of birds at Charcoal Tank Nature Reserve, on the 9th November.

The trip was led by Mark Clayton as usual and in over eighteen years of study this was the first of this species caught there. The Black-eared Cuckoo is a national widespread bird, but rather uncommon and can be difficult to find by birdwatchers. So I felt it appropriate to add a few pointers on the bird's plumage to help others identify one if they do ever have the fortune to come across one.

The distinctive face of a Black-eared Cuckoo
There is no mistaking the bird as a cuckoo in Australia, but a couple of us with experience of northern hemisphere birds considered it as resembling a Northern Wheatear, due to its soft orangy plumage and dark eyestripe.

This bird had a rich pale orangy breast - a deeper colour than the expected buff
The under-tail barring is characteristic of the Bronze-cuckoo genus Chalcites.

The coverts on the wing were well worn and faded
The bird was quiet in the the field when we saw it and in the hand after it was caught, which might explain its elusiveness.

There was very little contrast between the underwing coverts and the faint wing bar across the primaries, secondaries and tertials
I did not see the underwing bar as being particularly noticeable in the field, nor in the hand. But the white tips to the tail caught my eye immediately.

The light grey rump contrasted with the back, wing and tail.
And the tail showed distinctive fault bars.
The overall glossy sheen on the back and wings was like those on other Bronze-cuckoos, although not so bright, nor green as in the other species.

Tuesday, 12 November 2013

Spotlighting

Male Plains Wanderer - difficult to see in grassland, even under spotlight
Last week I was out with Peter Cosgrove on a bridwatching trip organised by Philip Maher and led by his colleague Robert Duncan. We looked around for honeyeaters, chats and waders in the late afternoon before driving over some grasslands looking for Plains-wanderers Pedionomus torquatus with a spotlight. These birds are not nocturnal, but they are easier to see at night for during the day, they crouch when approached and become very difficult to see. At night they stand still when under a torchlight.

The female is brighter coloured with a distinct collar and rufous bib
Other birds seen during the night trip were Banded Plover Vanellus tricolor, Inland Dotterel Charadrius australis, Stubble Quail Coturnix pectoralis, Little Button-quail Turnix velox and Australian Pratincole Stltia isabella. 

Stubble quail - female
All in all, a very successful trip and thoroughly recommended for anyone who would like to experience a night out with the birds in the Riverina area of New south Wales.

Australian Pratincole

Thursday, 31 October 2013

Frogmouths in the sun

A Tawny Frogmouth basks in sunshine
Ever wondered what tawny Frogmouths do when we aren't watching, and they don't adopt their broken branch pose? Following on from the previous post, I thought I should add some images of how frogmouths hold themselves when not in alarm, as usually seen by humans.

Typically, they sit on the sunny side of trees where they can bask in the sun. Frogmouths can go into torpor during the day when they are not active and exposure to maximum sunshine, especially in winter, helps them thermoregulate. When sitting in the sun, they hold their breast up towards and face onto the sun. And they tilt their head back and fluff out their feathers, which are held tight against the body when in branch-pose.

Well shaded eyes
Frogmouths don't hunt by day and they hold their eyes closed when their head is angled towards the sun or when approached. But at other times when they are looking around, generally watching, their eyes are well shielded from the sunshine by thickly feathered eyebrows. As their eyes are likely better tuned to night vision, this probably aids their daylight vision, by shading them from bright direct light.

Quite frequently, they will bend their head right back and over a shoulder, spreading the feathers on their neck and breast wide open. This seems to be to allow maximum sunlight or heat reach their skin. In the photograph below, the bird has tipped her head to her left and her bill tip and nasal bristles can only just be seen protruding from the fluffed up plumage.

Maximised sun basking
A close call

A Tawny Frogmouth sits on its nest, hiding from me, not the Crimson Rosella 
Tawny Frogmouths are well known to adopt a branch-pose to hide from potential predators, as they usually do when approached by a human. So it was illuminating to watch what they do when an animal predator approaches them.

Yesterday, this bird was unconcerned when a Crimson Rosella landed on its nest branch, but quickly slipped into the angled pose as I drew nearer. Then while I was looking for the female roosting a few trees away, she began to call in a low oom oom. This is most unusual as they do not normally call at all when approached. And then she started to fidget, leaving her branch-pose and shifting along her perch. Her eyes were wide open, they keep them closed when approached as part of their concealment, and I was wondering what was up, when I heard a cawing back beside the nest.

The female frogmouth in alarm
Two Australian Ravens were hopping about in the tree next to the nest, staring at the bird on the nest, which was back in a branch-pose. She had obviously seen them approach the nest well before me and was anxous as to what to do. For frogmouths are loath to fly in daylight, yet she seemed to want to help chase off the ravens from her nest.

Two Australian Ravens investigated the frogmouth on the nest
The male by then had his hackles partly raised, and his bill was slightly open. I suspect that he might have been giving a low hissing call as the ravens drew closer. I am sure they had identified him as a bird on a nest, but perhaps his partial threat display was enough to make them unsure. We can't tell, but they flew away to join the rest of the roving flock which they were part of. Hopefully not to return. 

Fortunately they flew away

Wednesday, 30 October 2013

Fledging Frogmouths

A Tawny Frogmouth fledgling basks in the sun
The first Tawny Frogmouths fledged at the weekend, with one chick leaving the nest a day before its siblings, which left the next day. So, a brood of three from the earliest nesting attempt of the year, by the same pair which laid earliest last year and reared three chicks then too.

Meanwhile its dad continues to brood two chicks in the nest on the next branch
The female was sitting low in a branch and was most un-noticeable. Then once they had all fledged the whole family moved into an adjacent tree. They will continue to move around their home range from now on, roosting in a different spot most days.
 
And mum watches on in-obtrusively