Monday 23 September 2013

Breeding season feathers

Adult Laughing Kookaburra
I was out helping Mark Clayton with several others at a cooperative bird-banding site over the weekend, out by West Wyalong in New South Wales. The season is warming up now and there was a heavy fall of rain several days prior to our visit. Many of the birds were breeding, and I noted how we were catching more male than female birds, probably because the females were doing more incubating.

It was also a good chance to see adult birds in full breeding plumage. Although, as most of them had moulted into that plumage months ago, some of their flight feathers were beginning to look a bit tatty. This Laughing Kookaburra Dacelo novaeguineae, was an adult, although it could not be sexed because it did not have a large blue patch on its back like a primary male would have. As it only had a small blue patch, too small to even see in these photographs, it could have been either an adult female, a young female or a secondary male. Kookaburras are cooperative breeders, and the males also incubate the eggs, so even the presence of a brood patch was no help in sexing this bird.

The bird had a well developed brood patch: a large patch of bare loose skin, with a rich vascular supply






It was still early in the breeding season, so the birds had not yet begun to moult. They all had full sets of old flight feathers on their wings and tails.

A full set of flight feathers
Some of these feathers were beginning to fray at the tips, through wear and tear as the birds go about their business, flying through branches and catching their tails on the ground. The central tail feathers are particularly prone to wear as they project farthest and take most of the abrasion, so they are usually the first to show signs of age. Most of these birds will begin to moult out these battered feathers and grow replacements as the breeding season progresses.

The pair of central tail feathers on this kookaburra's tail are well frayed.

Thursday 19 September 2013

Sugar Glider

A tree came crashing down today
While I was out looking for Tawny Frogmouths today I heard a crash and looked around to see an old tree fall down. I thought it might be interesting to see what animals had been disturbed, or lost their home as I could see that the tree was very old and had some cosy holes for animals to sleep up in.

Sue enough, as I approached, a Sugar Glider  Petaurus breviceps slipped out of a broken branch and scuttled up the nearest standing tree. It wasn't too alarmed by my presence, but did go high up very quickly. For that is their strategy to escape, they can climb well, but they can fly too. And when it reached the highest branches it simply jumped into space and glided onto the next tree about twenty metres away. It landed on the top of another dead tree which it clambered down until it found a hole it could wriggle into. And that was that, a new home, safe from predators.

The Sugar Glider dashes up a tree

Once up high, the glider stopped to watch me. The folds of skin which help it glide can be seen rippled along its flanks.
Meanwhile, take a look back at the first picture. There are a pair of frogmouths up in the tree, in the top left. I noticed the male's tail protruding out from the nest after the glider had disappeared and I could re-focus my attention to my original purpose. 

The male frogmouth is on the left, on the nest, his partner is on the branch above


Tuesday 10 September 2013

Tawny Frogmouths at night

The moon and Venus above the female frogmouth
I was out watching the frogmouths last night with Steph and Matt. There were a pair which appeared with fledged chicks last year from an unknown nest site, so we staked out the area at dusk. The female was calling from her daytime roost perch for ten-fifteen minutes as the light faded. Then as it became truly dark she shifted to another perch and continued to call her rapid repeating 'ooom-ooom'. The call is distinctive, but so soft, we wondered how far away her mate was. The call only carried to our ears for about fifty metres. Do they do so to avoid attracting attention from their main night-time predator, the Powerful Owl? Then the male swooped in silently from the shadows and landed right next to her. She twitched her tail, he jumped onto her back and they mated for a minute or so. He then went off and hunted, catching an insect from some foliage up in a tree. She flew over to their nest site and continued to call. 

So, we accomplished our quest to find the nest site and all this happened in about half an hour immediately at the onset of true darkness. There is so much to see in the dark.

The distinctive silhouette of a Tawny Frogmouth - a broad, bushy head and a tapering tail 

Monday 9 September 2013

Bearded Dragon

Flat out
The days are warming up and the first of the larger reptiles have been out and about. The Shinglebacks Trachydosaurus rugosus are wandering slowly about the bush and others like this Bearded Dragon Pogona barbata are spending much of the days warming themselves up in the sunshine. This one was well camouflaged with its dusty skin matching the open dirt between the grass tussocks. It lay motionless as I stepped past it; its legs hung down along its tail, its skin spread out and the whole body aligned with the sun, all to maximise capture of the radiant heat.

It seemed to be trading off the powers of its concealment against the expenditure of its limited energy, having just warmed up a little and not being very active yet. For it was keeping a steady eye on me in case I did after all pose a threat and it would have to use that little energy to flee.

An eye watches through the camouflage

Thursday 29 August 2013

Tawny Frogmouth laying egg

The female gathers her newly-laid egg
Last night the female of the Tawny Frogmouth pair which I have been recording nest-building, laid her first egg of the year.

The male who had been covering the nest all day, left at 1813 hrs and the nest was left unattended until 1918 hrs when the female arrived with a twig of nesting material. After she found a place for that in the nest, and spent about ten minutes arranging the other material, she settled down in a relaxed position. She was evidently breathing deeply as her head and shoulders were heaving up and down - something they do not usually do when on the nest. So, I assume she was preparing to lay. Then after about twenty minutes, at 1949 hrs she got up and turned around, gathered an egg under her breast and re-settled down to incubate. This she did for about four hours, when her mate arrived with a twig. She left to hunt and he continued to incubate after gently settling over the egg with his breast feathers fluffed up to expose his brood patch. He incubated the egg for an hour and a half, before she returned for a further two hour session. Then they did an hour each, until the male took over a half hour before dawn. After which he was on the nest all day while she roosted in a nearby tree.

To view a short two minute video of the sequence, click here . Although, as the camera is activated by movement, and these birds are very stealthy movers, there is a time delay and they can enter or leave the scene unnoticed. They are like ghosts in the dark.

Tuesday 27 August 2013

Gang Gang Cockatoos


A pair of Gang Gangs inspect a potential nest hole

There seemed to be parrots everywhere in the bush yesterday as they were all prospecting, exploring, or defending nest holes. This  hole looks a bit too large for these Gang Gang Cockatoos, although there might have been a tighter cavity down at the bottom, so the male went in for a look-see. These parrots are such quiet and approachable birds and the male's bright red helmet is very smart.

The male seems to have dipped his head into a pot of red paint lying in the hole







































The twist of red feathers from the back of his head over the crown is a small but
spectacular piece of plumage. She also has a crest, but it lies tucked away. The female's plumage is just as well evolved as the males, although more for the purpose of concealing her. She has a fine pattern of bush-colouring, which hides her well as they sit quietly in the trees. These birds are easily overlooked, unless one is familiar with their subdued creaky calls, or their habit of dropping crunched-open gum nuts to the ground below.

The female has kept her head clean


Friday 23 August 2013

Tawny Frogmouths building their nest

A female Tawny Frogmouth adds material to her nest
Spring is approaching fast in Canberra, where although the nights are still cold, the days are warming and lengthening. And in response, the Tawny Frogmouths are building their nests more industrially. Two weeks ago, only a few pairs had even began to build, now I know several pairs which have well-built nests.

I set up a camera at a nest to record which of the sexes does most of the building, and from the limited sample of only one pair so far, it looks like the female does more. In one night, she spent about six and a half hours at the nest, bringing in twigs, shuffling them into place and sitting on the nest for long periods of time - I don't think there were any eggs yet, but the camera did not look down into the cup. The male spent about two and a half hours doing the same, although he was also on the nest all day before, plus for about an hour post dusk and pre dawn. They don't build large elaborate nests, just a simple platform which is enough to form base to lay their eggs on, so they don't bring in much material. The female brought in twenty-seven twigs and the male thirteen. Last week, only the male attended the nest, and he brought in just one twig, a short time before dawn.

To watch a few minutes of their edited nest building click here

I plan to set the camera up at other nests to record the effort of  a larger sample of birds.

Sunday 18 August 2013


Red-browed Finches feeding behaviour


Heads up
A flock of Red-browed Finches Neochmia temporalis have recently begun to feed on the seed I provide for birds, in a hanging dish. There are over thirty in the flock, but it is seldom, if ever that they all come to feed at once. There are always some holding back in the adjacent trees, keeping lookout?

Certainly, when they are in the dish, where their small bodies are entirely below the dish's rim, they cannot see and so look for potential predators approaching. Whether there are two, three or twenty in the feeder, there is always at least one with its head up watching for any sneaky sparrowhawk. Even with the camera set at high speed continuous shooting, I was unable to capture a shot of all the birds with their heads down. Nearly, but not quite. Flock feeding and shared alertness, with subsequent warning to the whole flock are well known, but intriguing to watch in action from the breakfast table.

Heads down

Saturday 17 August 2013

Feral Cat

A feral cat lies dead on a road in Namadgi National Park
While driving through Namadgi National Park yesterday I came across a dead cat lying in the road. It was still in good condition, although had been killed probably during the previous night. On closer inspection I was struck at how these feral pests have reverted towards their original type pelage of brown stripes on a grey base.

Considering how there has long-been a fashion for boldly marked cats within the pet market, such as black and white, or long or short-coated, and these are the source of many feral cats, such colourations are seldom seen in the wild. Not by me anyway. The last cat I saw in the wild was also in Namadgi and it was of similar colour and size. One driving force is likely selective predation by, for example eagles. I have not seen feral cats killed by eagles in Australia, but in Scotland where I have done much more study of eagle prey, I have found the remains of pie-bald cats, but none of type-coloured animals. Any boldly marked cats are more likely to be seen and killed first. Evolution in action, a second time around.

The markings are feint, but true of type.
This animal is close to the true European subspecies of the wildcat Felis silvestris silvestris, with the generally striped body and ringed tail, although the disruption of the stripes into spots are indicative of domestic cat Felis catus. As the tail is quite thickly haired, it does not fit the form of any warmer climate sub-species such as African (Felis silvestris libyca) from which the domestic cat is considered to have originated, or Asian Felis silvestris ornata, which have slender tails. Nor is the tail really thick and club-shaped with thick continuous dark rings as in the Scottish Wildcat. So, I would conclude that this cat's ancestry originates from a mixed European domestic stock.

The thick, ringed tail is indicative of a European wildcat type

Friday 16 August 2013

Kookaburra bill


Birds often develop deformed bills and I wonder why they occur, accident or disease. I met this Kookaburra in the bush yesterday, and I recognised it by its distinctive bill shape from last year. It was in the same area and probably the same family group's home range as it was displaying with another bird. So although it appears that it might have difficulty feeding with such a long upper mandible compared with the lower one, it must be successful. Kookaburras catch most of their prey by pouncing down on them from a perch and snatching them with their bills. Typically, they catch anything from insects to small reptiles, so they need to be quick and efficient.


Thursday 15 August 2013

Camouflage

Which bird attracts the eye first, least, the sunlit or shadowed one?
Tawny Frogmouths are well known for their ability to blend into their background, yet they repeatedly impress me with their exhibits of just how well they do so. Here are some shots of birds roosting in the daytime close to their nest trees as they enter their breeding season for 2013.

The male sits on the outside, as in about 90% of cases of pairs roosting together

A short stubby branch of the main trunk is a favourite perch
Another bird in the neighbouring territory sat alone, basking in the late winter sunshine. The freckles on her breast merging so well with the dappled shadows.

Easy to see once we know where to look

Thursday 8 August 2013

Tawny  Frogmouth nest-building

A possum investigates the camera
The birds'  breeding season has begun in south-east Australia and the Tawny Frogmouths have started to build their nests. I set the camera trap up at a nest last night and a short version of the results can be seen here on the this video link: Nest building .

The male bird was perched next to the nest when I set up the camera just after dusk, and he sat and watched me quietly with no sense of alarm. Then all was quiet until near midnight, when a Brush-tailed Possum came and sniffed at the camera. No birds came to the nest until six-o'-clock the nest morning, when the male brought in some fresh twigs or fronds and added them to the basic nest. And that was it for the night. Dawn was not far away.

Then at nine in the morning, An Australian Magpie came and investigated the nest, then jumped over to check out the camera.  A quiet but unexpected sequence of events. But Spring is here.

Sunday 28 July 2013

Northern wader habitat

A road meanders north through the extensive birch woodlands and mires
There are few human settlements or other intrusions to the landscape of the region in northern Norway where we go to study waders and the potential breeding grounds for these birds is vast. The forests and mires form a massive extensive mosaic of birch woodland and sedge-filled mires, with many open stretches of water in the form of tiny to wide lakes and formidable fast-flowing rivers.

A typical mire with open water in the centre surrounded by a floating carpet of mosses and sedges, and the whole encircled by willow/birch scrub and birch forest
Waders such as Wood Tringa glareola and Broad-billed Sandpipers Limicola falcinellus, Jack Snipe Lymnocryptes minimus, Red-necked Phalarope Phalaropus lobatus and Reeve Philomachus pugnax nest in the mires, while species such as Whimbrel Numenius phaeopus, Spotted Redshank Tringa erythropus and Greenshank Tringa nebularia nest in the scrub and woodland.

Numerous other northern breeding birds live in the these habitats, mostly summer migrants which go there to breed, then return south to over-winter. One resident species is the Willow Ptarmigan Lagopus lagopus which nests in the forest understorey. These birds can live there throughout the winter because they feed on the leaf and flower buds of the birch and willow which protrude above the blanket of snow that covers all the ground all winter.

A hen Willow Ptarmigan sits on her nest in juniper scrub

The ptarmigan's eggs are cryptically coloured to conceal them while she leaves the nest, perhaps once a day, to feed.

Arctic waders

Adult Wood Sandpiper
Here are a few photographs of waders and their chicks which I was studying recently in northern Norway. Part of the work, which is organised by my brother Rab, involves finding and catching both adults and chicks to ring them in order to help discover such information as where they live in the non-breeding period, whether they return to nesting or natal sites, and how long they live.

A pair of wood sandpipers, ringed and ready for release
The most abundant wader species in the tundra mires is the Wood Sandpiper Tringa glareola and the Broad-billed Sandpiper Limicola falcinellus is one the less common and seldom seen species. Most of the waders live in extensive mires, hidden by lush growth of sedges and other marsh plants.

An adult Broad-billed Sandpiper is measured -  the sexes are similar in plumage, but can be differentiated by size
Wader nests and chicks are notoriously difficult to find due their cryptic plumage and seclusive behaviour, arctic-breeding species are especially so. Wood and Broad-billed Sandpipers nest in the mires and it takes very specialized skills and a very very keen eye to find them.

A Broad-billed Sandpiper nest and chicks lie hidden in a mire

Broad-billed Sandpiper chicks in the nest





Four Wood Sandpiper chicks, a typical brood size
A single Wood sandpiper chick is extremely difficult to see when creeping through the sedge

Sunday 21 July 2013

Scotland 2013

Ben Loyal
Spring in Scotland seems a long time ago now as I have been looking through and cataloging the photographs from then, when I was in the Highlands studying birds and exploring the hills. Most of my time was spent in the far north-west in Sutherland where I was studying greenshank, golden eagles and ptarmigan.

I seem to recall that the weather was cold with a north wind blowing most of the time and lots of low cloud on the hills, with much late-lying snow. However, I reckon that there is always something to photograph in the Highlands, whatever the weather. It all adds atmosphere and reality to the images.

I have posted a short portfolio to my website, just follow the link on the right.

Cape Wrath sunset

Monday 15 July 2013

Lichen article

Lecanora campestris grows on an old headstone
While I have been away in the field studying waders and eagles, I missed the publication of one of my articles on lichens in the May edition of the Leopard magazine. This is such a wide topic with thousands of species in the UK alone, so I focused on readily accessible species which people can find growing on gravestones.

Lichens can be difficult to identify, partly because some need to be keyed out to microscopic or chemical characteristics, but also because so few have common names. Scientific double nomenclature can put people off, and in the case of lichens seem overwhelming. I am a scientist, but I do not like aloofness, I like to share my knowledge and experiences of wildlife with people. And the more I share, the more I find I learn. Perhaps if more people were to become interested in lichens more of them would gain common names? Do not be afraid of scientific snobbery, get out there and enjoy the variety of colour and shapes which abound in the wild outdoors 

Xanthoria parietina grows on a gravestone where bird-droppings enrich the surface

Thursday 4 July 2013

Red-spotted Bluethroat

Adult male Red-spotted Bluethroat
While in Norway studying the waders in the marshes, we were constantly surrounded by the songs of local passerines. The main species were Willow Warbler Phylloscopus trochilus, Mealy Redpoll Carduelis flammea flammea and Red-spotted Bluethroat  Luscinia svecica svecica. As there are few ornithologists working in the field in northern Norway, to help discover the wintering ranges of these birds, we ringed any passerine chicks we came across and caught adults in mist nests. The warblers and redpolls do not vary much in plumage between breeding and wintering periods, but the Bluethroats were spectacular in full breeding plumage, especially the males.

The blue throat
The blue-throat of these birds is truly stunning, being of a metallic hue. It is so bright and obvious when seen in the filed, however, when in the hand and viewed face-on, these birds exhibit a clear and bright yellow gape. The yellow line complements the blue and red tones so well, it must have a purpose in the bird's display.

The abundance of waders and passerines in the Arctic is largely attributable to the supper-abundance of mosquitoes. They can be a pest for field-workers, with their incessant buzzing and biting, but without them the mires would not be such a tremendous breeding ground for birds - so many species are dependent on them for rearing their young.

Mosquitoes are ever-present in the Arctic scrub


Broad-billed Sandpiper

A Broad-billed Sandpiper in breeding plumage
I have recently returned from a trip to Norway where I have been helping my brother Rab on a long-term study of the birds in the norther marshes, including the breeding biology of Broad-billed Sandpipers Limicola falcinellus. Typically of Arctic-breeding waders, these birds fly north to nest as soon as the snow melts and their breeding grounds are clear enough for them to feed and build a simple nest on the floating mires. The main function of their journey is to find a nursery area for rearing their chicks, and the whole breeding period from egg-laying to fledging is over in a matter of weeks, Then the birds fly south to their wintering grounds, which to date are unknown for the Norwegian population. To help answer this question we began tagging birds with geo-locators, and plan to re-catch the birds next year to download data which should indicate where the birds have spent the non-breeding period, the longest part of their lives.

The broad bill
One of the individual characteristics of wader species is the specific bill shape, and the broad bill of these sandpipers is not usually appreciated when seen in the field in profile. However, when the bird is in the hand, it is obvious. As these birds spend most of their time in their winter quarters, it is likely that their bill is adapted for catching certain prey there, giving them advantage over other species for a specific food source. The bill is not only broad, but has delicate flutings along its length, which suggest that the bill is a very tactile and maneuverable organ, not just a simple horny probe.

The not-so-simple bill of a Broad-billed Sandpiper