Officially a Magpie-lark (Grallina cyanoleuca) but in various parts of Australia it is known as Mudlark (builds a mud nest), Peewee, Murray Magpie, Peewit, Little Magpie. A bit smaller than a domestic pigeon.
The white face and throat indicates a female.
50D 100-400 @ 400 1/2500 f6.3 +2/3ev iso320
Well captured in flight Colin:) Well exposed by the looks of things too, good work adding some exp. comp to the plus side. I think you could afford to slice a little off the top and right in terms of composition.
P.S. I sometimes call them Peewees too:o
Interesting that some birds get different names attached to them, especially locally. Good wingspread, and although I'd prefer more details under the wings that would have meant a blown face if more EC was applied in-camera. Some flash would have helped with this.
I like the pose. Maybe sharpen it a touch Colin. :) Males have a clearly visible white eyebrow, which you probably know already. It's just I look for that and nothing else. Six one way, half dozen the other I guess.