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.

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.

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


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