Wow, that is one good looking good and the dark background makes it pop. Perfect whites to my taste and good framing and sharpness. Since I don't know the species, not sure if the reds are overdone.
I like it overall for the same reasons as Fabs, but I'm finding all the scattered debris a bit much. You could also clone out (or patch) the small black dot on the chest. F/14 may have been much - I'm thinking opening up would have smoothed out the BG more and hid the many small spots found throughout. I like the look on this gull - the red bill is nice.
This is a great image with nice sharp details and the eye is super. I do agree the spotted BG is not ideal and a wider f stop may have helped reduce this.
Based on what I see on Australia's east coast - and I guess the NZ version is a subspecies being somewhat similar - I feel the reds are a bit too saturated.
It looks fabulous against the dark BG Simon as noted previously.
Lovely comp, and great contrast in colours. The whites on the chest are borderline, and agree with Daniel regarding the BG. More blur on the BG would work.