HiFert

We were out walking about an hour before sunrise today, the air was crisp but it promised a beautiful day. Silvereyes were abundant, most with the rusty flanks of the Tasmanian race – they should soon be headed back south. Red-browed finches, yellow thornbills, golden-headed cisticolas, superb fairywrens and brown-honeyeaters were all in their usual spots, singing up the sun.

A highlight was a juvenile black-shouldered kite calling from a low fence as two adults hunted the grassland. The breeding season is usually August to January, so these two got an early start. Within a week of leaving the nest the young birds are capable of hunting for mice on their own, and disperse fairly widely from the nest site, so this nest would have been close by. Their nest is generally located in the canopy of an exposed tree in open country, and there are a few large trees standing high above the surrounding mangroves and grasslands here that would suit.

Following the unwritten avian law on dealing with bird photographers, they had moved out of range by the time the light was good enough for a photo. So I filled a card trying to capture a willie wagtail hawking insects on the grass.

Stockton Channel

There was not a cloud in the sky for about an hour this morning, then the gloom descended again. Everything is green, however and bursting into flower. Brown and White-cheeked Honeyeaters, Silvereyes, Yellow Thornbills, Red-browed Finches, Grey Fantails, and Willie Wagtails, were among our walking companions.

Tarro

Indecision - “I’ll land here, no I won’t, yes I will, no I won’t”

Duck!

He seemed to be managing OK with half his top beak missing.

Hunter River

Between end of semester grading and several days of rain I haven’t had many photo opportunities, but caught this crested tern cruising the river at sunset.

Walsh Point

Just as I pulled up in the car at Walsh Point, where the north and south arms of the Hunter River meet, an Osprey flew in to land on a light pole. However I needed a new battery, and by the time I got the camera organised he was gone. I walked along the river with the dogs, hoping for gull-billed terns but only finding crested tern and silver gulls. Then my Osprey overtook me flying up the middle of the river. They have previously nested in the area, and it is the spot where I’m most likely to see them, but it happens rarely enough to be a welcome sight. He banked and turned immediately overhead, giving me some nice images.

Stockton Channel

Walking along Stockton Channel there were constant flocks of birds overtaking us.  Most were Noisy Friarbirds, though my practice on the bird counting game didn’t help me determine whether they were a flock of around one hundred birds doing laps, or whether there were thousands of birds. Smaller flocks included Scaly Breasted and Rainbow Lorikeets, Yellow-faced Honeyeaters and mixed Godwits and Curlew. White-breasted Woodswallows were still there in significant numbers, and a young Sea Eagle was being harassed by Ravens.

The Bird Atlas has animated migration maps for 35 different bird species across Eastern Australia.

Port Stephens Pelagic

From Newcastle to the continental shelf is quite a distance, so novocastrian birdos tend to head north or south to embark on Pelagic trips, to reduce the mainly uneventful travelling time. (BTW the stars indicate points where natural gas bubbles up.)  The Hunter Bird Observers have organised regular trips from Nelson Bay this year, and though they are all fully booked, I got a call to say a spot had opened up this weekend.

And what a trip it was. Even thirty year veterans were adding ‘lifers’ to their list.

Pomarine Jaeger

Fleshy-footed Shearwater

Brown Booby

Streaked Shearwater

 

Crested Tern

Tahiti Petrel

Wedge-tailed Shearwater

Red-footed Booby

Bird list:
White-bellied Storm-petrel
Wilson's Storm-petrel
Tahiti Petrel
Solander's Petrel
Sooty Shearwater
Streaked Shearwater
Fleshy-footed Shearwater
Short-tailed Shearwater
Wedge-tailed Shearwater
Brown Booby
Red-footed Booby
Pomarine Jaeger
Little Penguin
Great Crested Tern
Silver Gull
Pied Cormorant

Manning Point

Last weekend I went to Manning Point for a 24 hour camp with the dogs, lured by the promise of good weather, which didn’t eventuate. So this weekend we went back again. We’d barely set up the tent and put the billy on for tea when this young Square-tailed Kite circled the campground.

The Square-tailed Kite Lophoictinia isura is a medium sized raptor endemic to mainland Australia. It is a species which can spend many hours on the wing with little active flight and can be observed either soaring high over open country, scrub or woodland or close to tree tops and through the tree canopy. It is a specialist hunter of passerines, especially honeyeaters and insects in the tree canopy, picking most prey items from the outer foliage by skimming and circling just above or below the tree tops.

The paperbarks and eucalypts in the area were in full flower, attracting lorikeets and honeyeaters in the hundreds, so it would have been a top spot for him, though I’m pleased I didn’t have to witness his lunch.

The Square-tailed Kite is sparsely distributed throughout the Australian mainland, primarily within 250km of the coast and generally absent from treeless inland areas and from dense forests.

Flight Initiation Distance

I’ve been reading about flight initiation distance in birds – an issue of concern to wildlife managers as they try to reduce human disturbance by using FID to develop set back distances for paths and viewing areas in bird sanctuaries. And an area of interest for bird photographers.

While the benefits of leaving in the face of a predation threat are fairly obvious, there are also costs in leaving and benefits in staying (the energy costs in flight, the benefits in remaining in a good foraging spot or continuing an activity such as courtship), so birds could be expected to vary their FID on the basis of an assessment of the relative costs and benefits of leaving or staying.

In one study, observers walked towards a bird at a constant pace of approximately 1.0 metre per second, while maintaining eye contact, and recorded  the distance at which the bird initiated flight. Each flush was conducted using one of three different treatments: one person directly approached a bird; two people  side–by–side approached a bird; and two people directly behind one another approached a bird. The study found that invariably the bird flushed sooner when there were two observers, but that there was little difference in the FID whether the observers walked side-by-side or directly behind one another.

Another study found that for 64 of 68 species of Australian birds, the starting point of the observer had a significant impact on the FID. The further away the observer was when spotted by the bird, the greater the flight initiation distance. The researchers hypothesised that this may have been because of the energy costs of continually monitoring an approaching predator.  They also noted that a range of factors such as time of day, season of the year, and acclimatization to humans affected FID.

 Pied Cormorant

Nelson Bay Pelagic

Flesh-footed Shearwater Puffinus carneipes

  Wedge-tailed Shearwater Puffinus pacificus

Grey-faced Petrel Pterodroma macroptera gouldi

 

Arctic Jaeger Stercorarius parasiticus

Up at 4:00 to walk the dogs before heading up to the marina at Nelson Bay to meet up with 13 other HBOCers for a trip out to the continental shelf.

It was a perfect day, weather-wise, but it was still a challenge for photography with the birds flying side to side and the boat bobbing up and down. Once out past the heads we started chumming and gathered a flock of shearwater or muttonbirds, at first they were mainly Wedge-tailed, but as we got further out they were joined by equal numbers of Flesh-footed. A number of Short-tailed Shearwater followed our tuna-oil slick, but it was running straight into the sun, so no photos. Also seen were one Hutton's Shearwater, plenty of Pomarine Jaegers, and one Wilson's Storm Petrel - none being particularly cooperative where photographers were concerned.

Three Grey-faced Petrel came through regularly, stopping for their share of the treats. Two Arctic Jaeger flew past on a couple of occasions, with one landing on the water at a distance from the hubbub behind the boat. Silver Gulls close to shore, and Great Crested Tern, but none of the rarer terns. An Australian Gannet flew past at a distance and a Whistling Kite and a Peregrine Falcon flew up from the headland.

A Storm Petrel flew past the front of the boat and hung around for some time, well in the distance. Fourteen pairs of binoculars trained on the horizon couldn’t narrow the ID beyond ‘either White-bellied or Black-bellied’ though being summer, it was agreed that it was more likely to be a White-bellied Storm Petrel.

We chose the day of a huge game-fishing competition, so even out to sea there were plenty of boats with burley but we didn’t see the northern birds that we hoped would have come down with the warm currents. Getting back to the dock protesters from Friends of Fish had gathered to disrupt the Game Fishing 'weigh-in' so I didn’t hang around, though the penguins that are often in the harbour would have been a nice end to the day.

Newcastle Harbour

Common Tern, Sterna hirundo 

The early sun was behind this group of Common Terns feeding on a school of small fish in the harbour, so while they aren’t great images for ID purposes, I kind of like the effect.

The species is a non-breeding migrant to Australia, where it is widespread and fairly common on the eastern coast during summer. The subspecies occurring in Australia is predominantly Sterna hirundo longipennis. Reportedly “In non-breeding plumages, adults differ from those in breeding plumage by: white forehead and lores that merge to dirty white and black-streaked crown and black half-cap on the rear crown, nape and ear-coverts, and with a large black patch in front of the eye; pale grey rump merging into white uppertail-coverts; and a conspicuous black cubital bar and a dusky secondary bar on the upperwing and a dusky wedge on the outer upperwing. The underparts are also white. The bill is black, occasionally with a red tinge at the base, and the legs usually black or black faintly tinged with red.”

Common Terns are recorded in Queensland from September, and usually arrive in NSW from late September to October. They leave again in mid-April.

The number of birds wintering in in NSW are thought to be increasing, with greater numbers in some areas where they were previously scarce or absent. For example, in Sydney Harbour National Park, Common Terns were seldom reported before 1970 but more recent counts are typically of up to 60 birds.

Department of the Environment, Water, Heritage and the Arts (2010). Sterna hirundo in Species Profile and Threats Database, Department of the Environment, Water, Heritage and the Arts, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Tue, 16 Feb 2010 10:02:05 +1100.

Stockton Channel

There was a bit of a feeding frenzy in the Stockton Channel of the Hunter River this evening with a large group of Silver Gulls and Great Crested and Common Terns diving into a school of fish.

Walsh Point Reserve

A Swamp Harrier cruised past with a pair of Masked Lapwing in noisy pursuit.

(Windows Live Writer has a handy insert map feature)

Stockton Channel

These common terns are not so common around here. They spend the summers in Australia, roosting in estauries on sandbars or as here on conveniently place channel markers. Groups of fifty or so birds have been seen off Nobby's Beach during December, though during the summer up to a thousand birds have been reported on the sand bars in the mouth of the Brisbane river in Queensland. Fascinating to watch as they dive headfirst after small fish, but easy to fill a card trying to capture them in action.

Hunter Wetlands Centre

Eastern Great Egret

Maureen and I went out to the Wetland to see the exhibition of photographs in their recent competition. Pleased that our images had passed the first cut, we wandered around the many great pictures on show, then unable to decide between them, Maureen voted for my fairywren, and I voted for her swallow babies - conveniently hung side-by side.

Most of the egrets were now sitting on their eggs, though some birds were still putting final touches to the nest. There are far fewer birds than in recent years, though the ibis numbers seem to be growing. In addition the ponds at the wetlands are rapidly drying up, with the melalueca swamp where the egret colony is, now just black mud. There were several dead ibis young in the mud, and any baby bird who found itself bogged would exhaust itself before reaching firm ground. 80% of New South Wales is now officially drought stricken, with a further 15% borderline. A mere 5% of the state is unaffected by drought.

Coon Island, Swansea

Pied Oystercatchers

Hunter Wetlands Centre

Formally regarded as a subspecies of the Great Egret, Ardea alba, the Eastern Great Egret was recently elevated to full species status, Ardea modesta.

Avian taxonomy is no simple thing, complicated by the fact that there are a number of taxonomic authorities who do not necessarily agree on what to name a particular bird, and there are people who have known a bird by a particular name and are reluctant to change what they call it. Avibase gives the major authorities and their various scientic and common names for a species. Past taxonomy has been based on appearance, behavior, habitat, nest characteristics, etc., but most recently DNA hybridization techniques have been used with probably the most accurate results of any method.

Class: Aves

Order: Ciconiiformes

Family: Ardeidae

Genus: Ardea

Species: Modesta
Common Name: Eastern Great Egret

Whatever they are called, they are currently nesting at the Hunter Wetlands Centre and are busy fighting, making love, and building nests in a large colony in the paperbark swamp.