Hi Emanuele, Good tonla range, and a very powerful sky. Maybe a bit too powerful, as it diverts the attention from the rest of the scene, including the birds.
As to the composition, I believe that if you could've created a bit of space between the two poles in the water, the birds not only would've stood out better, but as they have a relatively low level of contrast and details, also would've taken up a more dominant role in the photo, if you see what I mean.
Just out of curiosity: why did you convert this photo to B&W? I can imagine the coloured version also look quite nice!
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