Hi Mats I like this image It is not your typical gull portrait
I think its a herring gull The pose is not conventional since the bird is looking away but here I like it since I'm getting the sense the bird is looking at something in particular. We do stress head angle but there are exceptions and this is one of them Like the overall density, it sets the mood, perhaps just a little lighter bg by the beak to have separation (just a bit)
I like the placement of the bird in frame and crop wise might take a little of the top for proportion !!! For next time you might close down one stop for extra dof Don't have to worry about the bg and have enough shutter speed !!! Also with soft fill light from a flash you can enhance the bird. Here you probably want to be at -2 or more I think flash ruins more images than we think !! I like your image a lot !!!!