Well balanced photo. The foreground is nicely colored and out of focus. While the bird is in sharp detail and toned well. I like the wide aspect of the photo.
The background is nice and does not compete with the main subject. The reed on the right wrap around over the head of the main swan nicely.
I am not sure why the submission did not do a little better. Probrably just over saturation of swan's in the challenge in general but I could find nothing wrong with your shot.
I think that showing them in the enviroment adds to the enjoyment of this image, the mirror style of the 2nd swan is nicely complementary to the first 8
I love the colors in this image, the deep greens against the white birds is really beautiful, this photo also has a soft dreamy feel about it that works very well. Nice work.