I don't know where to start, as this is my first critique on a photograph.
Probably the most important aspect of this photograph is the impact. Although the title is an important part of the deviation, you can still get the idea even if you ignore it. The 'two legged sheep' will certainly make you stare at it for a while. Not to mention the attitude of the 'poorly equipped' sheep, which brings a perfect finish to the image.
As for the technique used to achieve all these, it's irreproachable. The depth of field is incredible, along with the amazing details. Notice the autumnal leaves, scattered in the grass, and the astonishing 'sheepish' hair.
In addition, the wonderful light makes a calm atmosphere and the slight fog in the background reduces any unwanted details which might distract from the actual image.
All in all, this is an exquisite image which everybody should see!