Thursday 30 December 2010

Owlet nightjar


The weather is warming up now with a predicted high of 35 degrees tomorrow. The cicadas are singing loudly, very loudly, and most of the birds have fledged their young. Two late frogmouth nesting attempts have failed. I suspect the eggs were infertile as the birds had been sitting on them for longer than the usual incubation period with no sign of chicks hatching. There are chicks in two other nests and one pair are sitting on their third clutch of eggs having failed to rear chicks from two earlier attempts.

While checking one of these nests, I walked past a tree where Anthony had owlet nightjars last month. And there was a bird sitting at the entrance to one of the holes. It ducked back a little more into the hole as I approached, but stayed there looking out. These birds favour trees with multiple holes or with other suitable holes in trees within fifty or a hundred metres. If flushed by a predator they dart from one to another, with a confidence that says they know exactly where they are going.

I left this bird at peace and wondered at its plumage and posture. The big black eyes look so like knot holes in the tree and the stripes on its head blend well with the crack lines. Perfect camouflage. Or have they adapted a plumage pattern similar to that of sugar gliders which are common in the same habitat, and so gain benefit of less predation. The central stripe over the head, round face and large eyes all fit. Perhaps potential predators are less likely to attack a glider, e.g. a sparrowhawk which only take birds.

Friday 17 December 2010

Sparrowhawks

Yesterday it was goshawks, today a female collared sparrowhawk came into the garden, caught a house sparrow and promptly ate it. A few days ago a male sparrowhawk was hunting the sparrows in the garden, chasing them into the dense canopy of the trees. We were playing cricket at the time only a few metres below them.


Sparrowhawks are regular visitors to the garden and they probably nest in someonelse's garden nearby. The goshawks are mostly in the woods. Both species are feeding large young now so there will be a heavy demand for them to provide food. As we have free range chickens in the garden sparrows come in to feed on the chicken food. It is usually the male sparrowhawk which catches the sparrows and smaller birds such as young starlings. The larger female usually catches Indian mynas, crested pigeons and rosellas - crimson and eastern.

Thursday 16 December 2010

GoshawksA female Brown Goshawk sits on a branch near her nest and young screaming sharp alarm calls.

Many of the Tawny Frogmouths have failed at their breeding attempts this year and some have disappeared from their nest areas. I suspect that in territories where no further nests were built the missing birds might have been killed and eaten by the Brown Goshawks. So I have been noting the distances between goshawk and frogmouth nests. The vacant frogmouth territories are about 100-200m from the nearest goshawk nests and there are wider distances between frogmouth nests in areas where there are goshawks.

One frogmouth pair have failed twice this year and I noticed a Collared Sparrowhawk nest in the tree next to the second nest. Sparrowhawks are smaller than frogmouths, but aggressive, so perhaps they disturbed the frogmouths enough for them to fail at their nesting attempts. That pair of frogmouths are now on a third clutch of eggs about 150m away from the previous nests.

While I was measuring the distances between these nests the goshawks were very defensive of their nests and young. They repeatedly swooped at me. Their speed is astonishing and it was interesting to be in the situation of a small bird being attacked. These birds are efficient killers.


The female goshawk launches off to attack me.


Her flight is straight and deliberate.


Her eye contact was fixed, determined and focused on me.


It was only in the last metre or so that she pulled out and skimmed over my head. Thankfully they did not attack me with open talons as they would a small bird, her feet are dropping into partial attack position, but the sharp claws are turned in. She was too close and quick for the camera to focus.

Wednesday 15 December 2010

Banding birds at Moruya

Last weekend I was helping Anthony Overs catch and band birds in the escarpment forest at Moruya. Michael and Sarah Guppy are working on a long-term project studying the local birds' breeding behaviour, so several banders went down to catch as many as possible and band them with individual combinations of colour bands. Michael, Sarah and Anthony have been doing this for several years and by marking the birds this way they can determine which bird is paired with which, where they nest and how many chicks they rear. The Yellow-faced Honeyeater above is the most abundant honeyeater in the forest, and there were many birds with flying young.

The adult male Scarlet Honeyeater below, the only one we saw, was probably passing through the area with flocks of other birds post breeding. There were also many adult and juvenile New Holland Honeyeaters.

The adult male Spotted Pardalote below, is another common bird in the forests. They are unusual in foraging in the canopy, perhaps a hundred feet up, but nest in self-dug burrows in a broken bank of exposed soil.


We caught several larger birds too, including Noisy Friarbirds, a Satin Bowerbird, a Crimson Rosella, a King Parrot and the adult Black-faced Cuckoo-shrike below.

The last bird we caught on the Saturday evening was an adult female White-headed Pigeon which was lured down to seed.

Thursday 2 December 2010

Rain and more rain

It has been raining every day and most of each day for the past five days, and the same on all nights. So I have been out checking on the frogmouths as several broods have been due to fledge this week. The brood below looked ready to leave the nest a few days ago, but they are still there, probably reluctant to fly while it has been raining. There are two chicks, one out of view and they are too big now for the adult birds to cover them during the heavy rainfall. Although they are still only half-grown and quite downy, they seem to have faired OK and are now hopping about on the nest branch and ready to fly off. The adult female is now sitting on the nest branch, having spent the past two months sitting in nearby trees. They seldom roost in the nest tree itself, probably to reduce attraction of predators to the nest. Then they often come in close to the nest to roost as the chicks near fledging.


The pair shown below have been less fortunate. They had two chicks the last time I saw them before the rain, now they have lost them. It might have been the weather that caused this, or a predator, I don't know and there were no signs or corpses below the nest tree to indicate what had happened. Now the birds are sitting on branches tight underneath larger branches. This gives them shelter from the rain which can be seen running off the bark of the branch above the female. The male is above her on a separate branch, his tail cutting into the top right of the photograph. This was this pair's second nesting attempt this year, the first having failed to predators, probably a possum.



Tuesday 16 November 2010


Tawny frogmouths fledging

Most of the tawny frogmouths have fledged young now or nearly so. The male below has two chicks which have been out of the nest for about two weeks. Although there are still several other pairs which have failed to breed successfully this year and others which are on second clutches of eggs or broods of young, after losing their first to predators - goshawks or possums?

This male's partner was one of the two females shown below. They were sitting together in the next tree from the male. Both birds have very similar plumage - these birds have diagnostic individual characteristics in their plumage. They have the same redness of their coverts especially. Why would the mother of the chicks allow a second female to approach them, let alone sit right next to herself? The second bird is probably related to her. Possibly a daughter from a previous year?

Monday 15 November 2010

Peregrine falcons

Last week I was in Victoria helping Victor Hurley band peregrine falcon chicks, as part of a study he has been running for the past twenty years. I am familiar with these birds from doing the same thing in Scotland, but the variety of nests sites in Australia was interesting. There were the conventional and most common inland cliff sites, where the birds lay their eggs on bare ledges in the cliffs.
Then there were nests in tree holes. These were in very old trees. One was about 25m up in a temperate rain forest, just below the canopy, others were in river red gums on the banks of the Murray River. Some, like the one below, were in red gums standing in flooded river beds - swamps with lots of cormorants, ibis and herons nesting in the adjacent trees.

Other nests were in quarries, old and currently in use. Some were in nest boxes deliberately erected for the birds high on the sides of factory buildings.

Then there were sites which I am familiar with in north-east Scotland, sea cliffs.
These birds stooped aggressively at Victor as he abseiled down to the nest for the chicks.
Then again when he went down a second time to return the chicks.

Thursday 21 October 2010

Masked plover

Today I found a recently dead Masked Plover by the roadside, after it had obviously been killed in a collision with a car. These birds are common around Canberra where there are many grassy expanses adjacent to the city streets. It is often chicks which are road casualties. This adult had probably been herding its chicks away from the road when it was killed as I had seen the family party at the same place yesterday.

The adult birds have distinctive yellow wattles on their faces, hence their name. And an alternative name for them is Spur-winged Plover, by which they are equally well named.

The spur is in the equivalent position as our thumb, and could be regarded as a highly adapted thumb-nail/claw. It is firm and rigid and would certainly be a deterrent to predators or competitive birds.

Tuesday 19 October 2010

Return after fire

The frogmouths which had abandoned their nest after a fire have returned. They have either come back to continue incubating the eggs, or they have relaid a new clutch in the same nest. I will know which when they hatch, by dating the incubation period. Perhaps if they have returned to the old eggs, they might not hatch if they were chilled at night or overheated in the sun during the day when uncovered.

Wednesday 13 October 2010

Bird banding at Moruya

Last weekend several of us from Canberra went down to Moruya to catch and band birds in a patch of forest. This was to individually mark birds with colour bands so that Michael and Sarah Guppy can follow the breeding biology and habitat use by a range of passerines. The bird above is a Red-browed Finch.

Micheal and Sarah have been studying these birds for several years, and it is all done on their own land so access is easy and the whole project is very well organised. We quickly set up a base station in the forest and started catching birds.

One of the more abundant and studied species is the Superb Fairy-wren, a male is shown here being delicately measured.

Another study species is the Brown Thornbill - the bird shown here clearly shows how readily the birds can be individually identified by the unique combination of colour rings which each bird is given.



















We caught 146 birds altogether of numerous species, and we had two Olive-backed Orioles in one net. The sexes are very similar, but can be distinguished. The male, here on the left, has slightly more green about his throat as can be seen in these photos.

This spectacular bird with a bald head and splendid Elizabethan ruff is a Noisy Friarbird. They mostly forage high in the canopy so it was unusual to catch one. Although these features are readily seen in the field, when in the hand they can be studied more closely. Why do they have a bald head? They are members of the honeyeater family, so this could perhaps help keep their plumage clean of sticky nectar? And look how they have retained eyebrows - a sensible adaptation to keep the rain out of their eyes? What is the purpose of that horn on top of the bill? And when did you last see a birds ears so clearly? Great birds.

Wednesday 6 October 2010

Orchids

Several species of orchid are now in full flower on Black Mountain in the middle of Canberra. There are over 50 species known for the local patch of dry hilly forest. Here are a few shots of the more abundant species.



A group of Wax-lipped orchids, stand erect with single flowers.

A colony of Nodding Greenhoods stand on a mossy gully bank. Many of the smaller green orchids are easily overlooked.

A single Nodding Greenhood.

A cluster of Pink Finger Orchids. Their flowers dot the ground all over the forest.

A Black Mountain Leopard orchid. A species thought to be unique to the ACT region, but locally common and many are now in flower.

Monday 4 October 2010

Echidnas

While out looking for frogmouths today, I came across three echidnas, two males and one female. She was having a siesta with her head tucked under a log, the males were sniffing around, following her scent trail - its the mating season.

Echidnas are quite furry animals really, with a layer of fine hairs beneath those sharp spines.

Saturday 2 October 2010

And now fire
Two days ago I noticed smoke rising from a patch of bush where I new there was a frogmouth nest. The park rangers were burning ground litter in the wood to reduce fire danger to the nearby suburbs. They did well, and the ground cover was only lightly burnt when I went in the day after. And no trees were damaged or canopy burnt. However, there must have been intense smoke during the burning and a bit of heat and flame - enough for an incubating frogmouth to desert his nest. This might not have been too much of a problem if they could safely leave their eggs during the day, but only fifty metres away was a pied currawong nest with young. They are predators of frogmouths eggs and young. The exposed white eggs of a frogmouth, left unguarded would have been an easy meal for the currawongs.


A few flames still licked on the day after. The frogmouth nest is up below the canopy.


This was the male sitting on the nest before the fire.


Now the nest is empty and abandoned. The currawongs were feeding their young in their nest while I was visiting the site. There was no sign of the frogmouths.

Wednesday 29 September 2010

Mixed findings

Spring is rolling on and yesterday I saw a fledgling Horsefield's bronze cuckoo being fed by a pair of buff-rumped thornbills. And today I found a grey fantail incubating one egg.


Fantail nests are delicate eggcups of cobwebs balanced on a thin branch. They always have a tail hanging down which seems to break up their outline and reduces the risk of predators seeing them.


Meanwhile, predators seem to be finding the frogmouth nests. In the past few years, only a few nests have been predated, but this year eight have been lost so far. Currawongs or possums might have taken some eggs or young, but some nests have eggshells and young lying below them, so they hadn't been eaten by them. I have seen brown goshawks most days when I have out in the bush, and one pair which have abandoned their nest have a goshawk nest only 25m away. And I found the plucked remains of a chick on a branch not far from another nest which had been raided.

A dead frogmouth chick of less than a week old lies below its nest.