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


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.