One of the surest signs of a changing climate is being provided by birds. There is now irrefutable evidence from the northern hemisphere, based on observations of bird migration, that species such as migratory ducks are shifting their wintering grounds northwards in response to warming weather patterns. In Australia there is also mounting evidence of similar trends with one study (Smith et al, 2012) noting … “We examined a dataset of first arrival and last departure dates for breeding and non-breeding migrants at Blaxland, west of Sydney, from 1980 to 2011, for temporal trends and for relationships with climatic variables. The 16 species whose arrival dates were analysed have been arriving, on average, 4.4 days earlier per decade. Six species are now arriving significantly earlier than in the 1980s and no species is arriving significantly later.”
Locally we are also experiencing some changes in bird movement patterns, although the extent to which they are being influenced by climate change is less clear. Other factors, such as land use intensification, are also playing a role.
The Black Kite Milvus migrans, is one of Australia’s most common raptors. Anyone who has travelled to northern Australia will probably recall large flocks of these birds. They are most commonly associated with human habitation, sometimes gathering in their hundreds near abbatoirs and rubbish-tips. Over the past decade they have been an occasional visitor to our district, usually as singles or groups of a few birds at a time.
Yesterday afternoon I was astonished to see a flock of ~40 circling high above the broiler farm complex near Joyce’s Creek. This is by far the largest congregation I’ve witnessed in our area, but consistent with other recent observations in central Victoria. A single Black Falcon and a couple of Whistling Kites were associating with the flock.
Part of the Black Kite flock – including a single Black Falcon at top right!
The distinctive fork-tailed silhouette can be seen in these two individuals.
Reference: Smith, P., and Smith, J. (2012). Climate change and bird migration in south-eastern Australia. Emu 112 (4) 333-342.
are a constant source of wonder.
Great Egret, Joyce’s Creek, 14th May 2013.
Black Kite, Moolort Plains, 15th May 2013.
Straw-necked Ibis, Moolort Plains, 15th May 2013.
Some readers may have gained the impression that Black Falcons are a ‘dime a dozen’ on the plains. Not so, although it’s a pretty good place to spot them on a regular basis. Two of their relatives however, are much more common – the slow and lumbering Brown Falcon and the dainty Australian Kestrel, both Falco species, like the Black Falcon. At the moment they are doing well on insects, especially crickets.
Brown Falcon, Moolort Plains, 13th May 2013.
The view from behind.
Australian Kestrel with cricket, Moolort Plains, 13th May 2013.
Eating small prey items on the wing is typical in Australian Kestrels.
If you have an hour or two to spare over the next little while, treat yourself to a visit out to the Moolort Plains. It’s a veritable raptor wonderland at the moment.
There are few places in Australia where you could hope to see ten species of raptor in an hour … but this is one of them, including the elusive Black Falcon Falco subniger.
Black Falcon, Moolort Plains, 12th May 2013.
Happy with this shot of a wheeling Black Falcon.
Note the long tail and lack of barring on the primary wing feathers of this Black Falcon.
Burnt stubble seems to be a great attraction to F.subniger.
In two brief visits over the past two days I’ve listed: Australian Kestrel, Brown Falcon, Spotted Harrier, Whistling Kite, Black Kite, Black-shouldered Kite, Wedge-tailed Eagle, Little Eagle, Brown Goshawk and multiple Black Falcons.
by Chris Johnston, Green Gully
Gentle rain, autumn. Moths! There must be 50 beating on my windows, tracking the light.
Out in the garden, they are still emerging – a fluttering amongst the leaves. And then a swoop – a bat flits past in chase of a big supper?
Have a look at a previous posting on ‘moths after rain’ – http://geoffpark.wordpress.com/2009/04/26/goat-moths-after-the-rain/
and on the window sill
Courtship feeding is a well-known behaviour in the raptor family. It serves as a pair-bonding ritual and is a prelude to nest-building in many species. It may seem unseasonal to be thinking about breeding as we move into winter, but Black-shouldered Kites look to be getting ready. Locally I’ve seen them on nests in July, apparently incubating. Breeding is timed to coincide according to food availability, particularly mice in this part of the world.
Black-shouldered Kite with mouse, Moolort Plains, 10th May 2013.
About to make the aerial transfer – the bird at right is most likely the male.
Black-shouldered Kites are often quite vocal when courting.
A strikingly beautiful species.
I love that blood-red eye!
Remarkably, the Loddon River is flowing again. Despite little more than 75mm (that’s three inches of rainfall), since October last year, there is a tiny trickling flow gradually moving towards the town.
A trickle is better than nothing … by far!
This is not as a result of rain higher in the catchment, but from the network of underground springs upstream on the Loddon and along the Jim Crow Creek.
The Loddon River at the Punt Road ford, 8th May 2013.
Autumn spring flows are legendary in the district – I have little knowledge of this phenomenon and perhaps others can enlighten us about the history and cause of such a welcome sight. The birds are certainly happy!
Superb Fairy-wren (female), Loddon River @ Newstead, 8th May 2013.