I find myself paying a bit extra attention to exactly this deviation every time I go through my favorites.
On a purely analytical level this is quite a lot out of the ordinary, it's a bit shocking that there are foreign objects such as fish in what could otherwise be described as a quite ideal/idyllic scenery.
Which furthermore brings me to the intentions of the creator, or rather my beliefs of intentions. The fish has taken the most important role of a human face; the eyes. Additionally, I come to think that the human face gives a frame of reference to the fish eyes, ie you have given fish a mean of visual communication in the form of facial expression through a human medium.
Realizing this might be a long shot, I wonder what these creatures would want to communicate if they indeed did function in the way that we do. However, just thinking of negative exteranalities of fishing I get stuck on the amazement I feel towards the concept as a whole. And for me that is everything!