I know this must look strange. It looks as though the BG is a studio back drop. In reality this is exactly as was taken. The BG is a bluff over looking an estuary; the bird and the bluffs tones are so similar, that by the time the 500mm lense compressed the hues of the bluff it rendered them as a single mono-tone. This causes the bird to look as though it were copied and pasted into the BG. On a personal note I would like to have a bit more DOF on this.
EXIF: Camera: Canon 30D Lense: Canon EF 500 IS L / f 4.0 Metering: pattern Mode: apeture priority Exposure: 1/1000 @ f 9.0 / exp. comp -.33; fill flash -1.33 comp. ISO: 320 White bal: custom 5100 K Monopod
Lovely result. The colours work well and there is a bit of tonal variation in the BG. Lovely feather and eye detail, DOF looks OK to me. The lack of contrast on the perch is the thing that looks a little odd to me.
As per Tony, the first thing that I noticed was the way less contrasty perch. You select it and boost contrast to match the wren. Otherwise a very appealing image with an excellent complimentary BG colour :-)