Your image shows the different types of feathers and textures on the anhinga well. The background is interesting without being distracting.
I see a sharpening halo around the bird on my monitor.
The whites behind the bill don't show much detail, but it may be the feather type there.
The pose looks a bit awkward, but that is mainly because anhingas always look a bit mismatched. Needs to find a bigger head!
Thanks. Not sure what the halo is, I hardly needed to touch sharpening and can't see one on my monitor- something I always look for. Lack of texture in the white was my oversight in PP, it's there in the RAW image; I did pay attention to your advice on my recent Magpie shot Randy!
As for the head, well it's just a mechanism and guidance system for a speargun :D