#4

Good Focus.    Best use of the Rule of 1/3's. Subject is looking into the picture.  Nice S-Curves and lines Good Depth of field adds to the picture.  Hint of light in the  eyes adds appeal.

#1 

Good Focus and Lighting. Eye appeal. Contrast between the bird and the background.  Doesn’t fill the frame. Nice lines. Good head position

#3

Only 2 dimensional.  No depth of field or perspective. Good focus.  Centering does not help. Leading lines but  real doesn’t take one anyplace.

#2

Weak Focus.  Centered.  Doesn’t fill the frame.  Mounting problems.  Picture is too large.   Subject is looking out of the picture.