W/ Pics: 200mm NIKKOR Not Great Clarity?

My AF-S DX Zoom-Nikkor 55-200mm f/4-5.6G ED lens has been losing its stunning clarity. It is mounted on the Nikon D3100 (don't make fun.). When I first bought it, around November, the clarity of my photos was amazing. I received an iMac for Christmas and began using Aperture for my editing, instead of the simple Microsoft software.

Do you think it is Aperture, the lens, or even my computer that has changed or is losing the clarity? Or is making me think the clarity is dropping?

I took this photo today:

I'm not greatly pleased when I view it on the large full-screen iMac.

What do you think?

… Or is it just my inner critic?

Added (1). Oh yes, thank you for telling me it is dreadful. Really needed that. Not your decision, buddy!

The birds head looks tack sharp. The depth of field is just very shallow.

If you want more depth of field, you will need to stop the lens down more when shooting at longer focal lengths.

The sharpest lens aperture is two stops down from wide open. In the case for your lens, that would be at f/11 at 200 mm.

As you know, the longer the lens focal length, the shallower the depth of field at any given lens aperture

I think you don't really understand what you're talking about because you haven't defined exactly what you mean by "clarity". Do you mean sharpness? If that is what you mean, then say that. Clarity has variable definitions and isn't a word usually associated with lens performance. There are many things about that image that have more to do with its perceived clarity than the lens attached to your camera. It's angle, but moreover, as fhotoace pointed out, the head of the bird is sharp enough… Perhaps, depending on your eyesight. Not much else is because the aperture is set to f/5.6, wide open for that lens. I think in this instance, you answered your own question. Select a smaller aperture, f/11 perhaps, and keep more of the frame sharp. The concept is known as depth of field. Concentrate more on actual principles of photography to understand them, understand how they relate to things like sharpness, don't waste your time on words with made up meanings you may have picked up from an adjustment in your editing software or a lens review you read on the internet. There's nothing wrong with your camera, lens, or computer. Learn how to use them properly. And maybe work on your composition skills. That picture is dreadful.