Sunday, 23 March 2008

Little big birds

Wattlebirds are loud and argumentative but I do have a soft spot for them. A red wattlebird (Anthochaera carunculata) occasionally sits on the side fence watching me when I'm at the computer. I'm sure it's the same one, a sleek, well-fed bird with wattles like scarlet sealing wax and a splash of sulphur on its belly. It never stays around long enough for me to get a photograph. It lands on the fence with a thud (I did say 'well-fed'), poses picturesquely until I fire up the camera and then flies off. The fence is only two metres from my computer, so if I ever manage to get a photo, it will be a good one.

(Luckily, other people are more organised. Here are a couple of red wattlebirds I prepared earlier from Trevor and Duncan.)

I've managed to get photos of the red's dowdier cousin, the little wattlebird (A. chrysoptera). As the common name indicates, little wattlebirds are the smallest of the three wattlebird species. (Tasmania boasts the yellow wattlebird, A. paradoxa, which is so big that it would probably knock over the fence.) They don't possess wattles or any fancy patches of colour but the plumage is a subtle combination of earthy colours. They might not be as flashy as their larger rellos but they have a certain appeal.

Although all wattlebirds are related, the grouping is not as neat as might be expected. Red and yellow wattlebirds are sister species, occurring on either side of Bass Strait. Little wattlebirds east and west of the Nullabor Plain are also sister taxa. (They may or may not be different species.) After that, it gets a bit untidy.

Despite appearances, the red + yellow pair is actually more closely related to the regent honeyeater (Xanthomyza phrygia) than it is to the little(s). At first glance, it's all a bit odd. Regent honeyeaters are splendidly decked out in black and gold with white lace and not the modest mottles of the three (or four) species of wattlebirds. But those differences in plumage are counterbalanced by the similarities between the eggs. Furthermore, although regent honeyeaters lack wattles, they possess patches of bare skin around the eyes that are covered in warts. And there's always the genetic evidence, which provides pretty strong evidence for this grouping.

Images: I photographed this little wattlebird at Cape Nelson, SW Victoria. Like New Holland honeyeaters, little wattlebirds are abundant in the coastal heath but are difficult to pin down with the lens. Still, I've had more success with both these species than with the red wattlebirds. Go figure.


Reference
Driskell, AC & Christidis, L. (2004). Phylogeny and evolution of the Australo-Papuan honeyeaters (Passeriformes, Meliphagidae) . Molecular Phylogenetics & Evolution 31: 943 – 960.