Lots to like here Willem - very nice, smooth BG, good detail on bird and I really like that the feet are sharp and visible. Exposure looks good to me also. I would prefer a bit of a forward look from the bird, rather than this backward look. The perch is a bit dominating but in a way sort of suggests the fragility of the little guy in it - so not a big issue.
Head angle and tail merge are the two concerns here...do you have one where at the head is turned at least parallel to the sensor (or preferably towards us).
Good exposure, and I like the vertical comp. Nice clean BG too.
Willem, nice capture. I like the details and the smooth BG. I agree with the suggestions made above and I personally would have preferred a smaller perch. TFS.