I love all the offset lines and odd shapes of the blocks!! The rough texture of the water goes nicely with the texture of the blocks and color of the water blends in well; a nice earthy color palette.
Would you consider this a better photo if you were to remove the white flying bird because of the following:
-It throws off the line the birds are on. ( the birds aren't exactly in line but are close)
-It breaks the pattern of gray bird, white bird, gray bird.
-It is the only bird flying
-An even number of objects is less pleasing compostionally
Would you consider the balance instead? 2 standing birds, wings closed on the left and 2 open winged birds on the right.
My personal thoughts: The 2 birds on the right do add more weight to the right but they are not enough to balance that side with the large blocks on the left. I would opt for removing the flying bird. I don't think the 2 birds are enough to tell the story of birds battling for perches when there are 2 other calm birds present. Removing the flying bird would change the story to be that of birds resting in their favorite location. Mr Open winged heron could be stretching or drying his wings as opposed to warding off an enemy.
I would like to hear what your thoughts on what I see.
Please take my comments as what I see in your photo.