This is an example of a few things. First, it is the counter-pointing of two elements, the heads of the does, one facing forward, the other facing to the side. Odd numbers of elements are easier to compose, but counterpointing helps with even numbers of elements.

This also is a color photo so underexposed that it is really monochrome. It has been made into an abstract nature photo. Making a photo abstract often reveals the effectiveness of the composition because all the distractions of color are removed. Its all shapes here and they seem to work. The monochrome also makes the point that is is dusk.

Note that the heads are outside the third lines on the right and left as well. This creates tension right and left because it violates the rules a bit -- it certainly stretches the rules.

Photographers should not be afraid to experiment and challenge convention. At some time in the past, all rules were created the first time. Why not play the edges and see what you can find? This isn't film anymore, there is no financial risk in experimenting with new compositional strategies.