I'm not really sure this represents "wildlife" since there is a banding tag on his leg. I like the photo though, just not sure that it represents the challenge well.
This is an interesting subject. The image is a bit too contrasty for me. This looks like the result of fill-flash. To soften the harsh effect of artificial light you can try taping a bit of wax paper over the flash. The other effect of flash is it is difficult to get a good catch light in the eye which is what adds the sparkle of life to a living subject in a photo. The background could be blurred quite a bit more to really isolate the bird, especially since this isn't a particularly colorful bird. The other way to isolate him a bit from a distracting background is choose a different angle of view, eliminating the tree trunk (which is very similar in color and texture) and placing him in front of a background that won't compete as much with his brown feathers. In this case the natural choice would be the green leaves. Particularly bothersome to me is the branch that appears to be growing out of the side of his head. This is an engaging subject and a nice effort. More attention is needed in terms of eliminating visual clutter.